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Module 9: Control Techniques 9-1

Student Text IAFF Training for Hazardous Materials: Technician©

Module 9:

Control Techniques

9-2 Module 9: Control Techniques

IAFF Training for Hazardous Materials: Technician© Student Text



Module 9: Control Techniques

Module Description

This module covers defensive and offensive control methods used by hazardous materials re-sponse team members. Basic confinement techniques such as diking and damming areoverviewed, while more advanced containment procedures such as plugging, patching, andoverpacking are addressed in more detail. Special considerations (transfer operations, for ex-ample) are also discussed.

Prerequisites

• Students should have completed a hazardous materials operations level training program.

• Students should have completed Module 7: Personal Protective Equipment and Module8: Decontamination, and demonstrated the required competencies.



ObjectivesUpon completion of this module, participants will be able to:

ObjectivesNFPA

Standards

NFPA 472 1-2

NFPA 472 4-3.1

NFPA 472 4-3.2

NFPA 472 4-5.1

NFPA 4724-3.5.1

NFPA 4-4.3.1

NFPA 4724-4.3.2

NFPA 4724-4.3.3

NFPA 4724-4.3.4

NFPA 4724-4.3.8

NFPA 4724-4.3.9

NFPA 4724-4.3.10

NFPA 4724-4.3.10

NFPA 4724-4.3.7NFPA 4724-4.3.5

OSHAStandards

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

29 CFR 1910.120(q) (6) (iii) (F)

• Describe the differences between “confinement” and “containment”operations.

• Describe the considerations of performing “offensive” operations.

• Describe methods used to reduce hazards before offensive actions aretaken.

• Describe basic procedures for reducing hazards while engaged inoffensive operations.

• Describe three basic techniques for reducing hazards of product spills/releases.

• Given a pressure vessel, select the appropriate equipment and demon-strate a method of containing leaks from the following sources: fusiblemetal plug, fusible plug threads, sidewall of container, valve blowout,valve gland, valve inlet threads, valve seat, valve stem assembly failure.

• Given a pressure vessel, demonstrate the ability to: close valves that areopen, replace missing plugs, tighten loose plugs.

• Demonstrate the ability to contain the following types of leaks in a 55-gallon drum: bung leak, chime leak, forklift puncture, nail puncture.

• Given a 55-gallon drum, demonstrate the following overpack techniques:rolling slide-in (vee roll), slide-in, slip-over.

• Given an MC 306/DOT 406, demonstrate the proper use of a dome clampto seal a dome cover leak.

• Identify methods, equipment and considerations in controlling a fire in anMC 306/DOT 406 aluminum shell tanker.

• Describe at least one method for containing the following types of leaksin MC 306/DOT 406, MC 307/DOT 407, MC 312/DOT 412, tankers:dome cover leak, irregular shaped hole, puncture, split or tear.

• Describe three product removal and transfer considerations for thefollowing overturned tankers: MC 306/DOT 406, MC 307/DOT 407,MC 312/DOT 412, MC 331, MC 338.

• Describe three safety considerations in product transfer operations.

• Identify the maintenance and inspection procedures for the tools andequipment used for mitigation by the jurisdiction, according to themanufacturer.



Instructor Preparation



Module 9Prerequisite Quiz

1. Most 55-gallon drums have openings in the top fitted with plugs and caps. These open-ings are called:A. BungsB. ChimesC. VentsD. None of the above

2. The best type of control technique for trapping solid materials floating on running wateris:A. An overflow damB. An underflow damC. A dikeD. None of the above

3. Oxygen gas would most likely be transported in which type of tank car?A. Pressure tank carB. Non-pressure tank carC. Cryogenic liquid tank carD. High pressure tube car

4. Which of the following is usually built to contain releases on land?A. BoomsB. DamsC. Diversion pitsD. Dikes

5. Which of the following statements is true of overpacking?A. Overpacking should only be used on 55-gallon drums.B. Leaking drums do not need to be sealed before they are overpacked.C. Overpack drums must be marked.D. Overpack drums must be made of plastic.

6. Which of the following control techniques are fire fighters usually responsible for?A. Off-loadingB. Venting and burningC. Product transferD. None of the above



7. Which of the following control techniques involves releasing gas vapors into the atmo-sphere to reduce tank pressure?A. Vapor flaringB. Hot tappingC. Cold tappingD. Venting

8. Which of the following items is often used as an adsorbent?A. SandB. SawdustC. Cat litterD. Clay

9. Cargo tanks can be constructed from any of the following materials. Which one is softestand will puncture most easily?A. AluminumB. Quenched and tempered steelC. Mild steelD. Stainless steel

10. Which type of tank car is the most common?A. Pressure tank carsB. Non-pressure tank carsC. Cryogenic liquid tank carsD. High pressure tube cars



IntroductionQuestions

1. What is the difference between “confinement” and“containment”?

2. What are three ways an overpack drum can be used?

3. Why are frangible disks designed to fail completely atspecified pressures?

You should conduct a hazard analysis at every emergencyresponse. A hazard analysis helps you determine what, ifany, offensive interventions are needed. At every incident,your response team should ask:• What is the product?• How much is there? (A lot/a little)• What is it doing? (Leaking product, releasing energy,

stressed?)• Where is it going?• How is it getting there? (Airborne, pressure, liquid,

heat, etc.)• Who or what is threatened? (Responders, public, envi-

ronment)• What will happen next? (Nothing? Get worse?)• What will happen if nothing is done?• Can we protect the threatened?• How? (Defensive or offensive?)• When? (Can we wait?)• With what? (Do we have the equipment and personnel?)• At what risk? (Is it worth it?)

Asking the simple question, “What will happen if we donothing?” can sometimes save a great amount of risk, cost,and aggravation. In some cases, no action is the bestaction. This is not to say hazardous materials teams shoulddo nothing, but the idea that offensive actions are alwaysindicated should be discarded. Instead, determine whatdangers actually exist and balance them against whatactions can be taken to reduce them. The response actionsteps outlined in Appendix B and the corresponding formswill help you balance risk versus benefit.



Safety

General Hazards

Besides obvious chemical hazards, other hazards may exist.They include:

• Physical hazards include slip/trip hazards, narrowwalkways, ladders, or electrical lines. If these hazardsare apparent, take extreme care. Better yet, investigatean alternative means of access.

Sharp edges on or near containers may snag or punctureprotective garments. Extra heavy overgloves and bootsor outer suit covers may be needed.

Many containment operations require extensive physi-cal effort. Making these efforts in chemical protectiveclothing is difficult at best, so the performance of theentry team should be carefully monitored.

• Environmental hazards are obvious, but often over-looked. Heat, cold, rain and snow will affect yourefficiency and working time, requiring you to makeadjustments. Also be aware that operations may start inlight, but continue into darkness; make sure you haveappropriate lighting on hand.

• Container hazards often cause injuries. A leakingcontainer indicates that some type of stress has oc-curred. Determining the source of stress causing thebreach can help you predict future container behavior.Pressure vessels are exceptionally dangerous. In addi-tion to the hazard itself, the container may rupture.

• Container stability is extremely critical. All theprotective clothing available will not protect you if acontainer falls on you. Assess the stability of a con-tainer and correct it, if necessary, before you begincontainment operations.

• Container integrity is an issue because if the containerhas already been breached, it has lost some of its integ-rity. The container must be able to support the contain-



ment techniques you chose. For example, a tank leak-ing product because of extensive corrosion will prob-ably not withstand the application of a bandage device.The device itself may cause further damage.

• Energy releases must be prevented when you areworking in the Hot Zone. Recognize that the containeritself may contain energy in the form of pressure. Inindustrial settings, other energy sources like motors,fans, presses, or heaters may activate automatically. Besure any electrical equipment is locked and tagged outbefore you begin work.

Ignition sources should also be controlled as a matter ofprocedure, regardless of the flammability hazards.

Basic Safety Procedures

Regardless of product or container, some basic safetyprocedures should be followed.

• Have a plan. Have a clear understanding of what youare trying to accomplish. As a team, you have a duty toeach other and to yourself to develop a plan and del-egate responsibility appropriately. If a plan cannot beimplemented because of unforeseen circumstances, theteam should back out and regroup, rather than goingahead with an impromptu plan.

• Stay away from the product. Walk around puddles,avoid kneeling in product or leaning on things, and stayaway from escaping gas plume. These practices shouldbecome second nature to experienced responders. Teammembers should watch out for each other.

• Have correct tools available. Labor saving deviceslike drum levers, dollies, and handcarts can preventstress.

• Reduce leaks before containing them. Many leaks/releases can be minimized or even eliminated by simplyre-orienting the container. Containers leaking liquidscan be rolled so that the breach is above product level.Containers of liquefied gases that are leaking liquid



product can often be moved so the breach is in thevapor space.

• Protect against fire. Whenever working with or nearflammable products, have charged lines of adequatecaliber and an established water supply. Based on thedegree of hazard, consider having charged foam lines.

• Stay alert. In the heat of the moment, responderssometimes develop tunnel vision. A single mindedfocus on a leak may blind you to other hazards such asa hole just in front of you, or a low bridge ahead. Forceyourself to step back and survey the entire scene andcarefully note changing conditions.

Activity



Confinement vs.Containment

Confinement and containment are sometimes used inter-changeably, but there is a difference. Confinement refersto actions taken to keep a material in a defined or localarea. Containment refers to actions taken to keep a mate-rial in its container.

Confinement

Confinement is the process of limiting a product spill (anair release, solid or liquid) to the smallest possible area.Confinement can often take place away from the actualproduct itself, and therefore is defensive. Well equipped,well trained operational personnel (first responders as wellas hazardous material technicians) should be capable of avariety of confinement activities. Always consider confine-ment techniques before you attempt containment.

General Confinement Techniques

Solids are perhaps the easiest products to confine. With thepossible exception of dusts, they usually remain where theyfall. Site control is one confinement technique. You canalso lay plastic sheeting or tarps over the spill to keep windand rain from dispersing the product.

Liquids present more challenges to responders. Liquidsspread, based on terrain and viscosity. They can also beabsorbed into surfaces.



• Diking or damming is perhaps the easiest method toconfine a liquid spill. A barrier (dirt, absorbent booms,plastic wrapped hose, sand, etc.) is placed ahead of thespill to prevent it from spreading. This keeps the areainvolved to a minimum and reduces the surface areaavailable for volatile liquid evaporation.

• Absorption/adsorption can be used with or instead ofdiking and damming. This involves the use of anothermaterial placed directly on the liquid. The liquid eithercompletely soaks into the product (absorbs) or adheresto the surface (adsorbs). This also prevents the flowand spread of the product and can make cleanup easier.

• Diversion channels liquids to another, less sensitivearea. On land, this is accomplished by dikes placedahead of the spill to force the flow to another area. Onwater, booms may be placed across the flow of water todirect a lighter than water product.



• Retention is the act of holding liquids until they can beneutralized, diluted or removed. Building a circulardike around a drum creates a retention pit for theproduct. Products may also be diverted to another moresuitable area for retention.

• Dispersion uses special agents to break up non-solubleliquids spilled in water. Dispersant agents are com-monly used on hydrocarbons (e.g., oil spills at sea), butdo not change the hazard itself.

Gases and vapors present the most difficult challenges toresponders. Gases and vapors spread based on their proper-ties, the terrain, and the weather. They also present thegreatest risk to the public because they may travel longdistances from the site and manifest no warning signs suchas odor or taste.

• Confining a liquid spill to a small area by damming ordiking will drastically reduce vapor production. Thereare two other basic methods of confining a gas/vaporrelease.

• Suppression is used on liquids that are producinghazardous vapors. The most common type of vaporsuppression uses fire fighting foams on liquid fuelspills. Foam blankets the spill and prevents or reducesvapor production. Special foams for use on corrosivesare also available. Suppressing vapors does not changeor eliminate the hazard permanently; rather it reducesthe immediate hazard and allows responders time for abetter planned response.

Fire fighting foam used on a gasoline spill to suppress vapors



• Vapor dispersion consists of moving gas/vapor toanother area or diluting its concentration in air toreduce its hazardous effects. Fire fighters are taughtthat a large caliber fog stream can move great amountsof air via hydraulic ventilation. This same principal canbe applied to gas/vapor releases. Remember that thismethod will only move the hazard to another area orreduce its concentration, and that may be all that isnecessary to protect the endangered area. When fogstreams are used on water soluble gases/vapors, theproduct itself may be absorbed by the water. This maycause a residual hazardous, evaporating solution; butagain, it may be necessary for the protection of an area.

Containment

Containment usually refers to stopping or slowing a leakfrom a container. It can also refer to chemically changing ahazardous material to another, less hazardous material toreduce its dangerous properties.

Containment Techniques and Equipment

Containment activities usually involve contact with ahazardous product and requires that attention be given toproper PPE/CPC selection and decontamination.

• Neutralization involves adding a different chemical tothe spilled chemical to reduce or eliminate the hazards.This method is mainly used with corrosives. Thistechnique produces—in addition to the two originalchemicals—a chemical reaction from the neutralizationprocess, and a new, neutralized product. To select theproper PPE, you must research the original chemical,the neutralizing chemical, and resultant chemical.Neutralization is not always an effective way to miti-gate a spill and can create more problems than it solves.It can also be extremely dangerous. Neutralizationshould only be attempted by experienced teams withappropriate equipment and training. Obtain outsideresources to ensure a safe process.

• Overpacking is the process of putting the damagedcontainer and its contents into an undamaged container.



Overpack containers are typically 85-gallon plastic ormetal drums with sealable tops. Overpacking is typi-cally used with leaking 55-gallon drums, but can alsobe used for smaller containers such as jars, pails, car-boys, bags, and bottles. Overpacking is also used tostore used absorbents.

When using an overpack container, be sure to:• Use a drum made of material that is compatible

with the hazardous substance.• Use a drum large enough to contain the leaking

container and any spilled product.• Label the container with the name of the spilled

product and the words “Salvage Drum.”• Avoid placing too much product in the overpack

drum, which could cause overpressurization andleaks.

Pressure containers can be overpacked with specializedoverpack devices. These devices are extremely expen-sive and not usually carried by response agencies.

• Plugging is placing an object into an opening on acontainer, whether it is an engineered opening (e.g.,valve stem) or a stress related breach (e.g., puncture,rip, tear). Plugging devices can be made on-scene orcommercially purchased. Items used are woodenwedges, dowels, and tapered cones, expandable rubberstoppers, pneumatic operated neoprene plugs, screw-like devices—almost anything that is resistant to thechemical and can be tightly fitted into the opening.Pneumatic plugs ranging in size from a few inches toover three feet are available for large holes or pipebreaches.



• Patching is the placement of a material over an openingin a container. Again, these devices can be purchasedcommercially or made by responders. Patching itemsused include neoprene or rubber gasket material withwebbing, epoxy/glue patches, and sections of containerscut to fit various curves. There are many pre-made kitsavailable for use in plug and patch operations. Somemanufacturers produce kits that contain various sizes ofrubber stoppers, cone wedges, molly bolts for use withstoppers, different sizes and materials of gaskets, epoxypatches and web-type clamps. These can be used onsmaller leaks on any size container.

• Bandages can be used with, or instead of patches.Bandages, which are usually made of flexible metal,encircle the container to hold a patch in place. Theycan be pneumatically operated, tied, twisted, or tight-ened by toggle bolts.

• Auxiliary closure devices are meant to be used whenan engineered opening such as a valve, cover, ormanway has been breached. Dome cover clamps aretypically used on the manways of road liquid cargotanks. They fit over the dome cover of a manway andtighten down to press the cover back into position. Ifthe leak is caused by a faulty or missing gasket, domecover clamps may not stop the release completely.Dome clamps can be purchased in varying sizes. It isadvisable to carry more than one size and to carryenough to control breaches in all size covers you mayencounter in your jurisdiction. Kits are available forcylinders that allow you to place a hood over a leakingvalve. This hood contains another valve which can thenbe closed.



Activity

• Sealants are clay-like, chemically-resistant materialsthat can be used like putty to seal leaks from smallholes or tears, or to seal the area around a leakingplugging device. They can be a quick and effectivemeans to seal small leaks before overpacking or ban-daging, however they may not be effective when thehead pressure increases. Commercial sealants areavailable from a variety of sources. Most are resistantto fuels, and specialized corrosive resistant types can bepurchased.

• Engineered and provided methods refers to devicesthat are built into the container. Many fixed facilitycontainers have redundant valve systems which meansthe product can be shut off at more than one place. Ifyou can find a product control flow valve, you may beable to stop the flow without direct intervention. Al-ways check with the container owner or specialist todetermine that closing a valve will not cause a problemelsewhere.

The Chlorine Institute developed specialized contain-ment kits for cylinders and tanks transporting theirproduct. The “Chlorine A Kit” is designed to handlecylinders with a capacity of up to 150 lbs. The “Chlo-rine B Kit” is designed to handle one ton cylinders andthe “Chlorine C Kit” is designed to handle leaks fromdedicated rail cars of chlorine. Chlorine kit instructionsas well as manuals on chlorine, can be obtained fromthe Chlorine Institute, 2001 L St., N.W., Washington,D.C. 20036.

These kits contain a variety of materials and can beused to seal almost any kind of leak from a pressurecylinder of chlorine. They are large, heavy and veryspecialized but they do come with an excellent set ofinstructions and procedures. If a jurisdiction intends touse one or more of these kits, it is mandatory that youtrain with them on a regular basis and maintain profi-ciency in their use. An emergency scene is not theplace to learn how to use these items.



Purchasing Containment Equipment

There is a variety of containment equipment availablecommercially, ranging from relatively inexpensive rubberstoppers and wooden wedges, to expensive pneumatic plugsand bandages and specialized kits for cylinders.

Your primary concern, after your safety, is whether theplug, patch or other containment item will resist the leakingproduct. It is of little value to contain a leak, only to havethe containment device dissolve.

Based on your hazard analysis, you may need specializedcontainment devices and materials. Check with localindustry. They deal with leaks of their products on a morefrequent basis than you, and have probably developed orpurchased confinement and containment devices that workeffectively.

You can also fabricate your own devices based on thecommon hazards in your area. When making or buyingcontainment equipment, always consider the equipment’schemical resistance and ease of use while wearing CPC.

Develop a resource list of equipment available from indus-tries in your jurisdiction. You will need access to thisequipment to train and maintain proficiency in its use.

Auxiliary Tools/Equipment

There are many items used in containment activities thatdo not actually contain the product.

• Bung wrenches are specially designed tools used totighten the bungs and vents on drums. They are usuallynon-sparking.

• Non-sparking tools such as wrenches, hammers andclamps are used to prevent sparking in a flammableatmosphere.

• Drum levers help you upright drums by providingleverage.

• Drum dollies/carts are designed to help you movedrums easily. They typically slide under a containerand allow you to wheel it away.



Basic ControlTechniques

Assessing Damage

Use the following checklist as a guide for assessing dam-age, whether a release is from a cargo tank or a tank car:

Cracks:• Cracks are narrow splits or breaks in material caused by

fatigue or impact.• Cracks may lead to catastrophic failure in pressurized

containers.Scores:• Scores are reductions in thickness when the container is

indented.Gouges:• Gouges are reductions in the thickness of a container

when part of the container material is removed.Dents:• Dents are deformations in a tank caused by blunt ob-

jects.• Sharp radius dents may result in cracking.Burns:• Wheel burns result from constant contact with a turning

wheel which reduces the thickness of the tank car.• Rail burns result from a moving tank passing over a

stationary object.• Street burns are deformations in a tank shell caused by

sliding on pavement.

Points to Remember:• Damage may be to outer shell only and may be difficult

to assess.• Pressure containers may fail catastrophically.• Valves may not operate properly when they are in a

different orientation (sideways, upside down); this maybe the cause of the leak.

• If you are unsure of the container status:• Get expert help.• Take all defensive measures.



Control Techniques forNon-Bulk ContainersNon-bulk containers probably account for most hazardousmaterial calls. Many times they will be empty or almostempty when you arrive. Mitigation is often directed to spillcontrol or protecting undamaged containers.

There are a number of ways a non-bulk container can bedamaged. The container may fail completely as a result ofover pressurizing, shattering, or a BLEVE. Failure, how-ever, is not usually catastrophic. It is more common for avalve to leak or a container to be punctured. Occasionally,storage of incompatible chemicals causes container failure.

Generally, your spill control techniques will be limited torighting the container; tightening or closing valves, bungs,and clamps; repacking; and ensuring that pressure will notbuild up. Do not seal safety relief devices

Mitigation Methods

Many hazardous materials emergencies involve leaking 55-gallon drums. There are several methods for controllingdrum leaks.

Overpacking

Overpacking is one of the most common control techniquesfor leaking 55-gallon drums. However, before you attemptan overpack, make every effort to stop the leak.

Overpacking involves placing a leaking drum into a largerdrum. Overpack drums are usually made specifically forthis purpose. An overpack drum can be used in three waysdepending on the orientation of the leaking drum. Invertthe overpack drum and place it over the leaking drum. Tiltboth drums horizontally, then vertically, so the overpackdrum is oriented with its open top up.

If the drum is horizontal, use a slide-in method. Place theopen end of a horizontal overpack drum near an end of the



leaking drum. Raise the end of the leaking drum whileyour partner slides the overpack around the leaking drum.Then, push the leaking drum into the overpack and tilt bothdrums to an upright position. An alternative is a rollingslide-in or V-roll method in which you place the open endof the overpack drum under the rim of the leaking drum.Orient the drums so that they form a wide letter “V”. Pushthe drums from the apex of the “V” so that the rollingmotion causes the leaking drum to roll into the overpackdrum. Tilt both drums to an upright position.

Whenever overpacking drums, consider the integrity of theleaking drum. In overpack operations, the container willexperience a fair amount of stress. The weight of the drumshould also be considered. A nearly full 35-gallon drum ofsulfuric acid can weigh close to 600 pounds.

Plugging / Patching

Plugging and patching are other techniques for controllingthe flow of product.

Commercial Kits

Commercial kits usually contain molly bolts, screws,rubber stoppers, wedges, clamps, patches, epoxy, and otherassorted items. Kits are useful for small leaks on eithersmall or large containers. However, to use these items youmust usually come in contact with the product. Also, thearea around the leak must be in good condition—intact,strong, and not corroded.

Bandages

Metal, rubber, or plastic bandages can be wrapped aroundcontainers to make a seal. However, they must often beinflated to press against container and seal tightly. Inaddition, the area the bandage is applied to must be rela-tively strong.

Pneumatic Plugs

Pneumatic plugs can be used for mitigating pipe leaks.They range from four inches to three feet in diameter, andmust be inflated or expanded to work properly.



Sealants

Most sealants are clay-like materials useful for fillingpunctures. They must be compatible with flammableliquids, and may be used in conjunction with other tech-niques. They are temporary at best, and may not haveenough adhesion for high “head pressure”.

Areas of Drum Leaks

Before you attempt to plug or patch a drum, consider theeffect of this action. Many drums will be empty or almostempty when you arrive. Drums can leak for a number ofreasons and from a number of locations. If a drum isleaking from corrosion, a plug or patch application maycause further damage. It may be best to overpack withoutinitial containment.

Drums often leak from bungs, the small round holes in thetop of the drum. If a drum is leaking from a bung, roll thedrum so that the leak is above the product, then tighten thebung with the appropriate wrench. Many times, this will beall you need to do to control a leak.

If a drum is leaking at the chime (the rim), upright thedrum so most of the product is below the leak.

If a drum is breached on the side, and overpacking is notpossible, a plug or patch may be the best solution. Positionthe drum so that the breach is above the product. Some-times a combination of plugging and patching will ensure acomplete seal.



Small punctures, like nail punctures, are often hidden.Expose them by laying the drum on its side and observingfor the location of the leak. Then orient the puncture abovethe product. Sealants or plugs usually work well withpunctures.

Cylinders

Chlorine A and B kits are available for controlling chlorineand container leaks. These kits are used to control valveand plug leaks in 100-150 lb. chlorine cylinders (A kit) orton containers (B kit). Kits may be used on similar sizedcylinders, regardless of product. Chlorine leaks are con-trolled by placing caps over the leak area and forcing theminto place with leverage from parts attached to the tank.You must be trained to apply these kits. If your departmenthas them, make sure you receive regular training in theiruse.

Plugging/Patching Pressure Vessels

Containing leaks from pressurized vessels such as cylinderscan be risky, depending on the product, the amount ofpressure of the container, and the possibility of vaporclouds obscuring your vision.

These situations are difficult because of the specializedtools required to control pressure leaks. Most of thesedevices are designed for specific containers and consist of ascrew-on apparatus that allows the pressure to escape untila control valve is closed. If you have access to these tools,you should practice using them on non-leaking vessels.First, practice without protective clothing until the parts andprocedures are familiar. Then practice wearing gloves andSCBA. Finally, practice in full drills with chemical protec-tive clothing. Cylinders filled with compressed air canprovide more realistic training.

Leaks from pressure relief valves are not breaches. Pres-sure relief devices are designed to safely release containerpressure and to protect container integrity. Sealing them inany way may increase stress on the container system.



Control Techniquesfor Cargo Tanks

Over the road cargo tanks are found in almost every juris-diction in North America. Carriers include non-pressureand low-pressure tanks, high-pressure cargo tanks, corro-sive liquid carriers, and cryogenic liquid carriers.

Types of Leaks

Piping/Valve Leaks

Leaks from valves and intake and discharge piping arerelatively common on cargo tanks. They can be caused bylack of proper maintenance or by direct impact damage.You must fully understand the purpose and uses of variousvalves and pipes you may encounter. If at all possible,contact persons familiar with the tanker such as the driver,shipper, or carrier company. They can help you properlystop a piping or valve leak.

Piping leaks can be stopped by either closing valves ortightening packing. If piping is leaking, it is better to closea valve before the leak than to seal the leak. This contain-ment method limits product contact and risk.

The type of tanker and its product will have a substantialeffect on operations. MC 306/DOT 406 and MC 307/DOT407 cargo tanks use gravity for off-loading, minimizingpiping pressure.



MC 312/DOT 412 tankers use gravity and/or internal tankpressure to off-load. Pressure in piping may be near 75 psi.Leaking corrosives can cause additional chemical stress tothe outside of the tank, piping or valves.

Activity

Dome Cover Leaks

A dome cover may become loose and leak as a result of arollover. Dome cover clamps are used to stop this type ofleak. Cargo tanks, when not on their wheels, may beunstable. They may also have suffered physical containerdamage. If other damage to the container is not a problemand the tank is stable, you can apply the appropriate sizedome clamp. Obviously, you will not be able to upright thetank.

Physical hazards of the product become a serious concernin clamp operations because you will most likely haveconsiderable product contact during approach and contain-ment activities. Slip hazards will almost always be present.

Access may also present a problem. If the tank has rolledover, the covers may be beneath the tank. If the tank hasnot rolled over, you may have to use a ladder to safelyaccess the dome cover.

Tears/Irregular Holes/Punctures

Breaches in cargo tank bodies can be caused by vehicularaccident, rollover, or impact with other objects such asforklifts. Depending on the location of the breach, releasescan range from 2,500 gallons in a single compartment toover 7,000 gallons from multiple compartments. Thesetypes of leaks are commonly handled by hazardous materi-als teams.

Most of these breaches can be controlled with the samemethods used on smaller liquid containers like drums.However, you must plan for potential hazards of a largevolume release because of the size of the containers.



Although control techniques for drums are similar for tanks,tank breaches may be larger or require more control materi-als. You can purchase bandages developed specifically foruse with cargo tanks or large quantities of absorbents.

If the leak is above the product line, containment will berelatively easy. You will be able to apply the appropriateplug, patch and/or bandage with minimal product contact.As always, determine container integrity, especially in thearea of the patch or plug. This may be difficult, however,depending on the size of the tank and location of thebreach.

If the leak is below the product line, significant productrelease may be occurring during containment operations.You may not be able to apply plugs and/or patches becauseof the force of product flow caused by head pressure.Containing leaks of large volume flow is difficult at best,and will result in contamination of the entry team.

Another problem that may develop is the product’s reactionwith the outside container. Corrosives tanks are generallystainless steel or steel construction lined with butyl rubberor some other resistant material. If an MC 312/DOT 412has had a breach in that liner, the corrosive will contact thesteel outside the container and possibly work its way be-tween the liner/tank interface, seriously reducing the struc-tural integrity of the container.

Vents/Relief Valves/Rupture Disk Leaks

Vents are designed to allow normal vapor release. They areengineered to prevent leaks of liquid product if there is arollover. If liquid is being released from a vent, it hasprobably failed. You must consult with container specialistsand assess the risks fully to determine why the vent isleaking and the ramifications of containing the leak.

Relief valves are designed to operate in case a container isoverpressurized. MC 338 cargo tanks’ (cryogenic carriers)relief valves or vents normally operate as the product insidevaporizes, increasing pressure inside the vessel. If thecargo tank is not a cryogenic carrier and the relief valve isoperating, you should find out why. Do not try to contain



relief valve releases. If the vapors are causing a hazard,then efforts should be defensive.

Rupture and frangible disks are designed to fail completelyat a specified pressure. The theory is that a large releasethrough these devices is preferable to a container failure. Ifthese devices have activated, product release will be largebecause of internal pressure. Determine the cause of therelease before considering any action.

In all of the above cases, engineered safety devices haveactivated. Preventing their operation will result in furthercontainer stress. You must find out and correct the cause ofthe release before taking any containment action.

Inspecting DamagedCargo Tanks

Damaged cargo tanks must be thoroughly inspected todetermine the type and extent of damage sustained. Theseinspections can be performed by Technicians who have thebackground training in this area. Personal protectiveequipment must be worn during the inspection.

Examine all accessible surfaces for the type, location,direction, and extent of damage. If you cannot see theentire surface of the damaged cargo tank, reinspect itduring and after surrounding materials have been removed,or when the tank is lifted or uprighted. You must be experi-enced enough to determine the possible damage to the tankbased on its position (i.e., on soft ground or hard/sharpsurfaces).

Jacketed cargo tanks are difficult to inspect without remov-ing the jackets. Lack of damage to the jacket usuallyindicates that the tank has not been damaged.

Guidelines

Damage assessment and mitigation is generally not theresponsibility of fire department personnel unless special-ized training has been provided. The following guidelines



are for background information only. Do not attemptthese procedures unless you have been thoroughlytrained.

To inspect damaged pressure cargo tanks:

1. Examine all accessible surfaces for cracks, scores,gouges, and dents. Pay close attention to these types ofdamage that occur in the longitudinal direction.

2. Look for cracks on the tank. Relatively large cracks arevisible to the naked eye. For smaller cracks, the use ofa dye penetrant may be necessary. Since material oftenseeps through even small cracks, look for signs offrosting or clear liquid on the tank surface.

3. For each dent:• Identify dents that have scores or gouges associated

with them and those that cross a weld. (Dents withscores or gouges and/or dents that cross welds arethe most dangerous.)

• Examine each point of minimum curvature forcracks and, using a dent gauge, measure and recordthe curvature of all dents, no matter how small.

4. For each score or gouge:• Measure the depth of each score or gouge on the

tank to determine the extent of damage and risk.• Identify where each score or gouge crosses a weld.• Note when a score or gouge crosses a weld and

measure the depth of the removed weld metal.(When a score or gouge crosses a weld, the damageis more critical if it removes the weld’s base metalrather than just the weld reinforcement.)

• When a score or gouge crosses a weld, determine ifthe “heat affected zone” adjacent to the weld hasbeen damaged. (If the score or gouge has damagedthe heat-affected zone, the damage is potentiallycritical.)

5. Determine the temperature of the tank metal byattaching a thermometer to the shell of the tank; or, if atank is equipped with a thermometer, check the ther-mometer well.



6. Determine the internal pressure of the cargo tank.The internal pressure must be determined before thetank can be moved or off-loaded in place. The pressurecan be determined by:• Reading the tank’s pressure gauge• Reading the internal temperature gauge or

taking the temperature of the contents andreferring to vapor pressure/temperaturegraphs specific to the tank contents

If neither temperature nor pressure can be mea-sured, estimate the temperature based on ambienttemperature. (Remember that the temperature ofthe tank’s contents may lag behind ambient tem-peratures by up to six hours.) Since tank contentsmay stratify into different temperature layers,pressure estimated from temperature readings maybe lower than the actual pressure. Internal pressuresin empty cargo tanks that contain residual vaporsmay be equal to pressures in loaded cargo tanks.Vapor pressure/temperature graphs are availablefrom the Compressed Gas Handbook, the shipper,or the manufacturer of the material. When pres-sures are shown as absolute pressure, subtract 14.7to convert them to gauge pressure.

Many products are shipped under pressure of an inert gas(usually nitrogen) to preserve their purity. The inert gasprevents the material from reacting with air or moisture inair. Tanks used to ship materials this way are usuallymarked with a warning near the dome cover. Ambienttemperature and low vapor pressure of the product mayalso indicate that the product is under pressure of an inertgas. When a product is shipped under pressure of an inertgas, vapor pressure/temperature graphs will not provideaccurate estimations of internal tank pressure.

Even if you have conducted a thorough assessment, neverassume you have identified all the damage. Containerweakness cannot always be seen. As in other emergencies,the most dangerous hazards are those that are not apparent.



Inspecting and RepairingDamaged Cargo Tank Fittings

Many of the problems associated with cargo tank leaksinvolve valves and fittings. Once you identify the productinvolved, the source of the release, and the personal protec-tive equipment needed, you can begin considering controlmeasures. Often, releases associated with fittings can bestopped by tightening a fitting or re-closing a valve orcover. However, because the majority of cargo tanks areequipped with internal valves for product discharge, verylittle, if any, field repair can be performed.

The tables on the following pages describe, in some detail,the likely locations of leaks, probable causes for theseleaks, and basic control or repair methods.



Corrective Action for Cargo Tank Fittings

Location of Leak Probable Cause Basic Repair Methods

MANHOLE COVER

Liquid or vapor leak aroundmanhole cover

FILL HOLE COVER

Liquid or vapor leak aroundfill hole cover

TOP MOUNTEDSHUTOFF VALVE

Liquid or vapor valve leaking

Liquid or vapor valve leakingat tank outlet

BOTTOM OUTLETVALVES (internal orexternal)

Liquid leak at flange betweentank and valve

Liquid leak at end of off-loading pipe (s)

Loose clamp ring

Defective gasket

Not securely closed

Defective gasket

Valve not completely closed

Valve not seated

Defective seat or threads on valve

Loose flange bolts/nuts

Defective gasket

Internal valve not properly seated

Broken internal valve

Tighten bolt

To be handled by a cargo tankspecialist

Check for zero pressure, thenopen and re-close (do not if thetank is on its side); or

Tighten wing nuts or apply coverclamp

To be handled by cargo tankspecialist

Close valve

Tighten valve


Tighten valve bolts/nuts


Open and re-close valve




Location of Leak Probable Cause Basic Repair Methods

VAPOR RECOVERYVENTS

Liquid leak from vaporrecover line

SAFETY RELIEFDEVICES

Liquid or vapor leak fromsafety vent

Liquid or vapor leak fromsafety relief valve -- non-pressure tanks

Liquid or vapor leak fromsafety relief valve -- low andhigh-pressure tanks

Top vent not closed

Tank overloaded

Ruptured frangible disk (liquidindicated possible overload)

Melted fusible plug (liquid indi-cates possible overload)

Defective valve

Tank overloaded

Defective valve

Tank overloaded

Open and re-close top vent

Off-load product*

Replace frangible disk; off-loadproduct if necessary*

Replace fusible plug; off-loadproduct if necessary*

Replace valve

Off-load product*

To be handled by industryspecialist

To be handled by industryspecialist

*Many leaks can be repaired on loaded, but not overloaded, tanks; off-loading (or transferring) someor all of the product should be performed when the situation dictates.

Corrective Action for Cargo Tank Fittings



Handling DamagedCargo Tanks

Mitigation Methods

The following methods for handling damaged cargo tanksare prioritized from least to greatest risk. Again, do notattempt these procedures unless you have received specialtraining.

1. Make any necessary repairs and allow the vehicle toproceed to its destination for product removal. Repairsyou might be able to perform include replacing bolts,gaskets, or caps. You should not attempt repairs usingplugs or patches that could be dislodged.

2. Move the cargo tank a short distance to an off-loadingfacility or other safe area for off-loading (only if thetank is not leaking). The hazardous materials teamshould follow the tanker to that location in case of asecond spill.

3. Off-load the materials from the damaged cargo tank toanother cargo tank. This method should be performedby cargo tank specialists only.

4. Drill the cargo tank for product removal (non-pressurealuminum cargo tanks only). This method should beperformed by cargo tank specialists only.

5. On-site disposal by flaring (compressed gases in pres-sure cargo tanks). This method should be performed bycargo tank specialists only.

Field Product Removal Methods

Field product removal methods are those techniques used toremove the contents from a damaged or overloaded cargotank. All of these product removal methods are consid-ered outside the legitimate responsibility of the firedepartment. However, overseeing the planning andimplementation of these methods is within the realm offire department responsibilities.



These methods are discussed in this section to provide youwith enough information to oversee these processes andrecognize when inappropriate actions are taking place.Remember, protecting yourself and the community are yourprimary responsibilities.

Field product removal methods include:• Transferring• Venting• Flaring• Venting and burning

Transfers

A transfer involves moving the contents of a damaged oroverloaded cargo tank into a receiving tank (e.g., anothercargo tank, intermodal tank, or portable tank).

Often, cargo tanks involved in a rollover or other seriousaccident cannot withstand being uprighted if the tank isfull—this is particularly true of aluminum non-pressurecargo tanks. The product must be transferred prior touprighting and transporting the cargo tank if:

• The cargo tank has been damaged to the extent thatit cannot be safely uprighted or moved to an appro-priate off-loading facility.

• The tank itself is sound but, due to frame orunderstructure damage or other mechanical damage,it cannot be safely moved; or the damage to piping,valves, or fittings is such that it cannot be repaired.

• Site conditions prevent uprighting the tank (e.g.,terrain does not permit the use of air bags, cranes, orother equipment).

Safety Precautions When Transferring

The following safety precautions must be taken whenperforming a transfer:

• Limit site access to required personnel only• Allow only qualified and experienced personnel to

perform the work• Use appropriate personal protective equipment• Monitor site with appropriate vapor monitoring

devices• Have foam, dry chemical extinguisher, and



other suitable systems ready in the event ofaccidental release or sudden flare-up

• If transferring flammable or combustibleliquids (or finely divided solids) using anopen system:• Ground and bond the tank• Eliminate all ignition sources and prohibit

smoking in the vicinity• Eliminate or shut down electrical equipment that

is not intrinsically safe• Shut off internal combustion engines• Use an emergency shutoff system to either

automatically or manually shut down the opera-tion in the event of an unintentional release(caused by a hose failure or other malfunction)

Venting, Flaring, and Venting and Burning

For highway transportation, these procedures are rarelyused and are generally limited to pressure cargo tanks, suchas those transporting liquefied petroleum gas and otherflammable products. Flaring and venting and burning arealways last resort options and should only be performed byhighly trained and experienced personnel, only after allother options have been examined and ruled out. Accord-ingly, this discussion of flaring and venting and burning islimited.

Venting

Venting is the process of releasing flammable and non-flammable liquefied compressed gas vapors into the atmo-sphere to reduce internal tank pressure. This release can bedirect or (in the case of toxic products) indirect through anappropriate treatment (scrubber) or vapor recovery system.Typically, venting is used for non-flammable gases.

Flaring

Flaring is the controlled release and disposal of flammablematerials by burning from the outlet of a flare pipe. It isused to reduce pressure, dispose of the residual vapors in adamaged or overloaded tank, or burn off liquid whentransferring the liquid is impractical.



Venting and Burning

Venting and burning is a method of removing liquefiedflammable compressed gases or flammable liquids from atank by creating openings through the controlled use ofexplosives. Explosive charges are strategically placed onthe tank—one at the highest point on the tank for ventingvapor and the second at the lowest point on the tank forreleasing liquid. The released contents are allowed to flowinto a pit for evaporation or burn-off.

Venting and burning is the last resort and is to be performedonly by experienced personnel.

Vacuum trucks

Vacuum trucks are frequently used to remove liquid hazard-ous materials and waste from a response scene. They arespecifically designed and rated for certain types of hazard-ous materials and can develop vacuum for on-loading orpressure for off-loading. Vacuum trucks offer the advan-tage of not having to develop higher pressures in the dam-aged container. They can also be used to vacuum materialfrom the ground or other areas. A disadvantage is that theymust be placed relatively close to the damaged container orproduct.

Always consider the risk versus the benefit in responding toany situation that requires mitigation. You and other re-sponders should take every conceivable precaution toreduce risk.

Even though Technicians are trained to enter hazardousenvironments, their main focus should always be concernfor operational personnel and the fire service in general—protection of themselves, the public, property and theenvironment...in that order. Defensive actions should betaken first. Containment activities should be done onlywhen all other options have been exhausted or have notworked.

Activity



Special Considerations

Fire in MC 306/DOT 406 Cargo Tanks

MC 306/DOT 406 cargo tanks are usually constructed outof aluminum and are likely to be carrying fuels. They areused in almost every jurisdiction in North America todeliver gasoline and fuel oil. Fires involving these cargotanks are frequent so you should prepare for them.

Chemicals carried in these kinds of tankers often causelarge fires characterized by heavy smoke and radiant heat.Fires traveling a distance from the container, fueled byrivers of product, are also a distinct possibility. Because oftheir aluminum construction, MC 306/DOT 406 cargo tankswill melt rather than build up internal pressures that couldcause catastrophic breaching. If the tank does melt, therewill be massive product released and the remaining con-tainer (if any) will become a large open-topped vessel.

Non-Pressure Cargo Tank

Consider these incidents the same as any large scale flam-mable liquid fire. Rescue of persons trapped by the fire orradiant heat should be a priority; however, it may not bepossible to accomplish without a secure and adequate watersupply. You will need adequate personnel to handle numer-ous streams. It is often best to use large caliber, unmanneddeluge sets in areas of high risk.



These fires can be extinguished with the appropriate firefighting foam (for hydrocarbons, AFFF or protein willwork) at a specific rate for at least 15 minutes. Formulasfor calculating flow rates and amounts of foam and waterare contained in NFPA 11, Technical Standard of LowExpansion Foam and Combination Agents. AFFF foamwill help suppress vapors after the fire is extinguished dueto its film-forming capability. Whenever possible, providebarriers to escaping burning liquid. This will help reducesurface area and decrease heat production.

The availability of adequate water and foam reserves is thekey factor in your team’s ability to handle or extinguish afire in MC 306/DOT 406 cargo tanks. Incident Command-ers must carefully weigh their resources against theirstrategic goals. Water and/or foam may only be available toconduct rescue and protect exposures. If this is the case,the IC should delay extinguishing operations until adequateresources are on scene.



Control Techniquesfor Tank Cars

Damage assessment and repair on tank cars (just as oncargo tanks) should never be attempted by untrained per-sonnel. The information in this section is provided to helpyou understand—not perform—procedures for controllingtank car leaks.

You must receive additional training in this area before youattempt to control leaks in tank cars.

Inspecting and RepairingDamaged Fittings

Most unintentional releases of hazardous materials occur innon-accident situations as a result of improperly securedvalves, bad gaskets, overfilled cars, other unsecured fit-tings, and venting from safety relief devices. Whenever arelease occurs, you must work with the railroad to deter-mine the material involved, the origin and cause of therelease, and any potential problems. In addition, controlactivities should never be taken without proper training andappropriate personal protective equipment.

Once you identify the product involved, the source of therelease, and the personal protective equipment needed, youcan begin considering control measures. Many releasesassociated with fittings can be stopped simply by tighteninga valve or fitting using hand tools that are readily available.The most basic control measures for stopping releases fromfittings include:

• If open, close it (clockwise to close)• If loose, tighten it (clockwise to tighten)• If missing (but available), replace it

The tables on the following pages describe, in more detail,the likely locations of leaks, probable causes for theseleaks, and basic repair methods.



Corrective Actions for Tank Car FittingsLoading and Unloading Fittings

Liquid or Vapor Valve - Ball - or Plug Type

Liquid or vapor leak from Valve not completely closed Close valvethreaded orifice in valve

Plug loose or missing Tighten or replace plug

Plug or seat worn To be handled by a tank car specialist

Liquid or vapor leak from Loose flange nuts Tighten flange nutsseat between valve andthe manway cover plate Bad gasket To be handled by a tank car

specialist

Liquid or vapor leak around Packing retainer loose Tighten packing retainervalve stem

Missing split ring packing To be handled by a tank car specialist

Fill Hole Cover

Liquid or vapor leak around Loose cover nuts Tighten loose cover nuts hole cover

Fill hole gasket damaged To be handled by a tank car or missing specialist

Manway Cover

Liquid or vapor leak between Loose cover nuts Tighten loose cover nutsmanway nozzle and manwaycover Manway gasket damaged To be handled by a tank car

or missing specialist

Top-Operating Mechanism (Stuffing Box) for Bottom Outlet Valve

Liquid or vapor leak Loose packing gland nut Tighten packing gland nutfrom cover of valve

Defective packing material To be handled by a tank carspecialist

Location of Leak Probable Cause Basic Repair Method



Bottom Outlet

Liquid leak from Bottom outlet valve open Close bottom outlet valvebottom outlet cap

Bottom outlet cap/plug loose Tighten bottom outlet

Bottom outlet cap gasket To be handled by a tank car missing or defective specialist

Liquid Line Flange

Liquid leak from flange Loose flange nuts Tighten flange nuts

Missing or defective gasket To be handled by a tank car specialist

Corrective Actions for Tank Car Fittings (continued)Loading and Unloading Fittings




Corrective Actions for Tank Car FittingsPressure/Vacuum Fittings


Safety Relief Valve—External, Internal, or Combination

Liquid or vapor leak Loose flange nuts Tighten flange nutsfrom joint between base ofvalve and manway cover

Liquid or vapor leak “O’’ ring or washer installed To be handled by a tank carfrom valve seat incorrectly or damaged from specialist; do not remove the

normal wear. safety relief valveCaution: Spring may bebroken and is not repairablein the field.

Liquid or vapor leak Valve stem bent or broken To be handled by a tank carfrom valve seat specialist

Overloaded tank Unload; to be handled by a tank car specialist

Safety Vent

Liquid or vapor leak Ruptured frangible Replace frangible disk withfrom opening in center (rupture disk). Liquid new disk identical to theof safety vent indicates overload or splash ruptured disk

without overload

Vacuum Relief Valve

Liquid or vapor leak “O” ring off seat or valve To be handled by a tank carfrom under deflector stem bent specialistcap

Solidified product To be handled by a tank car specialist



Corrective Actions for Tank Car FittingsFittings for Gauging


Open-Type Gauging Device, Slip Tube With Quick Release or Screw Cover

Liquid or vapor leak Gauging device control Close gauging device controlfrom gauging device control valve not closed; valve valvevalve orifice plug plug is loose or missing

Liquid or vapor leak Loose flange nuts Tighten flange nutfrom joint between gaugingdevice and manway cover plate

Liquid or vapor leak Loose flange nuts Tighten flange nutfrom around cover at base offitting

Liquid or vapor leak around Packing gland nut loose Tighten packing glandgauge rod packing gland or retainermissing

Packing materials defective To be handled by a tank car specialist

Closed-Type Gauging Device, Magnetic

Liquid or vapor leak Broken pipe Tighten gauging devicefrom base of gauging cover

Do not remove cover.

Liquid or vapor leak Loose flange nuts Tighten flange nutsfrom seal between gaugingdevice and manway cover plate

Closed-Typed Gauging Device, Tape-Type

Liquid or vapor leak Loose flange nuts Tighten flange nutsfrom seal betweengauging device and manwaycover plate



Sample Line

Liquid or vapor leak Sample line valve not closed Close sample line valvefrom sample line orificeor from around plug Plug missing or loose Replace and/or tighten plug

Damaged sample line plug To be handled by a tank car specialist

Thermometer Well

Liquid or vapor leak Loose cap with damaged Tighten cap; do not removefrom thermometer well cap thermometer well pipe cap

Missing or defective “O” ringin cap or on nipple withdamaged thermometer wellpipe

Liquid leaking from Damaged thermometer well To be handled by a tank carbetween thermometer well pipe specialist; do not tightennipple and manway cover thermometer well nipple

Thermometer well Mechanical damage to To be handled by a tank carnipple broken off with thermometer well nipple specialistno leak

Heater Coil-Internal

Liquid leak from inlet Condensation from material Tighten capsor outlet pipes at bottom of used for heating contentstank

Washout

Liquid leaking from around Flange nuts loose Tighten flange nutsseal between tank andwashout plate Defective gasket To be handled by a tank car

specialist

Corrective Actions for Tank Car FittingsMiscellaneous Fittings




Handling Damaged Tank Cars

Mitigation Methods

Damaged tank cars should be handled as simply and safelyas circumstances allow. The following list prioritizescontrol methods from least to greatest risk. All of thefollowing shall be done by or with a tank car specialist!

1. Make any necessary repairs and forward to destination.

2. Move the car a short distance to a fixed loading/ un-loading facility for unloading (only if the tank is notleaking).

3. Conduct a field transfer—tank car to tank car.

4. Conduct a field transfer—tank car to cargo tank orintermodal tank container.

5. On-site treatment by flaring, neutralization, or othermethod.

6. Hot tap the tank car to facilitate transfer, flare, orotherwise unload the car.

7. Vent and burn the contents on-site.



Decision-Makingand MitigationWhether you are responding to a transportation or a fixed-site incident, you will be better able to identify the materi-als involved and make informed decisions about yourresponse if you can recognize basic vehicle and containerdesigns. Remember, however, that recognition and identifi-cation clues enable you to make educated guesses. Evenwhen information appears to be concrete it must be viewedwith caution. Always use clues in conjunction with refer-ence materials, shipping or facility documents, and reportedinformation before taking action.

All of the recognition and identification techniques pre-sented in this module can be reinforced with reliable infor-mation if you conduct and prepare an indepth pre-plan.Pre-planning takes much of the guesswork out of recogni-tion and identification.

Offensive OperationsDecision-Making

You will need to decide whether you have the training andresources necessary to undertake offensive operations.Answering the following questions will help you makethese critical decisions.

• What stresses caused the breach? (e.g., chemical,mechanical or thermal); are these stresses likely tocontinue?

• What is the identity of the product? Based on itschemical and physical properties, do you have theresources (e.g. overpack drums, foam, non-sparkingtools, neutralizing chemicals) to mitigate the situa-tion?

• Assess the defensive actions you have alreadytaken. Are these operations sufficient to ensure thesafety of the public, or is an offensive approachnecessary?



• If offensive actions are necessary, what is the riskversus the benefit to the entry team? Other respond-ers? The public? The environment?

• What are the hazards if offensive actions are nottaken? For example, is there likely to be a pressurerelease, or a reaction between incompatible chemi-cals?

• Can these hazards be controlled through offensivetactics?

• Can offensive control be done safely? Is the mate-rial stable, and can it be continuously monitored?

• Are you reasonably certain that your offensiveactions will have a positive outcome? For example,will you be able to patch a hole before the materialleaks completely?

Activity

Mitigation

If you decide that:• The situation warrents offensive tactics, and• Your team has the necessary training and resources, and• All operations can be carried out safely, then:

Proceed with the offensive containment tactics. Such ac-tions may include:• Uprighting leaking containers• Closing and tightening caps and lids• Repositioning a container so the level of the hazardous

material is below the breach• Decreasing container pressure by closing/opening a

valve, or shutting down a pumping system• Blanketing with vapor suppression agents, such as foam• Neutralizing a chemical by applying another chemical• Disposing of the hazardous material in place• Using clamps or pneumatic plugs to stop dome cover

leaks• Plugging or patching small holes• Applying inflatable bandages, straps, absorbents, and/or

wedges to larger leaks such as gouges and splits



Safety

While you are in the process of mitigating an incident,whether it is through defensive or offensive actions, keepthe following points in mind:• Larger containers may require climbing, so make sure

you have sufficient harnesses/ladders/high angle equip-ment to do this safely.

• Be aware of slip and fall hazards, particularly if largeamounts of material have spilled.

• Make sure the container is stablized before you attemptto control a leak; changing container orientation isusually not an option with larger containers.

• Be aware of routine hazards, such as traffic.• Do not attempt to move stressed containers, especially

if they are heavily loaded.

Remember the order of priority:

• Safety of the responder• Safety of the public• Preservation of the environment• Prevention of property loss



Application Exercise



Module 9Application Exercise



Exercise Assessment Sheet

Observe the student performing this activity and complete the checklist below.

Vapor Suppression/Neutralization Station Yes No

Did team member take colorimetric tube readings correctly?

Did team member apply sufficient foam blanket?

Did team member read pH paper correctly?

Did team member add soda ash properly?

Did entry team use absorbents/adsorbents properly?

Did entry team dispose of waste properly?

General problems/issues at Vapor Suppression/Neutralization Station:

______________________________________________________________________________

_______________________________________________________________________________

Diking Station Yes No

In general, did entry team assess situation correctly?

Did entry team use the appropriate tools?

Did entry team consider vulnerable water sources?

Did entry team build dike of sufficient strength and height?

Did diking contain the leak?

General problems/issues at Diking Station:



Plugging/Patching and Overpacking Station Yes No

In general, did entry team assess situation correctly?


Did entry team consider vulnerable exposures?

Did entry team correctly estimate size of release/contaminated area?

Did entry team adequately plug or patch the drum?

Did entry team use appropriate overpack technique?

Did these procedures contain the leak?

General problems/issues at Plugging/Patching and Overpacking Station:

______________________________________________________________________________

______________________________________________________________________________

Dome Clamp Station Yes No

Did entry team follow safety precautions?

Did entry team use the appropriate tools to apply dome clamp?

Did entry team apply dome clamp correctly?

Would dome clamp application contain the leak under actual conditions?

General problems/issues at Dome Clamp Station:



Chlorine “A” Kit Station Yes No



Did entry team identify the parts of the 150 lb. cylinder:Protective hood Valve Neck ring Foot ring Fuse plug

Did entry team properly apply the “A” kit to control:Loose valve Blown out valve Fuse plug leak Valve leak Cylinder wall leak

General problems/issues at Chlorine “A” Kit Station:

______________________________________________________________________________________________

Chlorine “B” Kit Station Yes No



Did entry team identify the parts of the 150 lb. cylinder:Protective hood Valve Neck ring Foot ring Fuse plug

OR, did entry team identify the parts of the ton container:Fuse plug Vapor valve Liquid valve Eduction pipe



Yes NoOn the 150 lb. cylinder, did entry team properly apply the “B” kit to control:

Loose valve Blown out valve Fuse plug leak Valve leak Cylinder wall leak

On the ton container, did entry team properly apply the “B” kit to control:Loose valve Defective valve packing Blown out valve Blown out fuse plug Fuse plug leak Valve leak Cylinder wall leak

General problems/issues at Chlorine “B” Kit Station:

______________________________________________________________________________

______________________________________________________________________________



Action Statement



Action Statement

You have just completed the ninth module of the Hazardous Materials Technician course. Thetopics included:

• The difference between confinement and containment• General confinement techniques• General containment techniques• Control techniques for non-bulk containers• Control techniques for cargo tanks• Control techniques for tank cars

Knowing how you respond to emergencies in your first due areas, would you change your actionsor habits based on the information covered in this module? Listed below are some suggestedactions. Some you may already do, and others may not fit your work environment. If there areactions you have not done in the past, do you think you will begin doing them as a result of thistraining?

As a result of this training I will:

1. Use more caution performing routine control techniques2. Practice control techniques while using chemical protective clothing3. Learn more about fittings4. Take additional training to become specialized in cargo tank repair5. Take additional training to become specialized in tank car repair6. (Create my own action statement)



Appendix A

Activities



Control Actions Activity 1

Based on the brief descriptions of each of the following actual incidents:

1. Would you take offensive actions?

2. If so, how would you have controlled the situation?

Case Study 1

At a hazardous waste cleanup site in Michigan, the EPA had been injecting lime beneath thesurface of a waste oil lagoon in an attempt to convert liquid wastes into solids. The injection wasstopped when a large white cloud was seen coming off the lagoon. Shortly thereafter, the lagooncaught on fire, apparently the result of an exothermic reaction. When the fire department re-sponded, they were advised that the lagoon contained waste oils, benzene, toluene, and xylene,but no PCBs.

Case Study 2

A truck driver in New York was hauling a load of assorted chemicals when he stopped along anexpressway to check his load. As he pulled over, several explosions occurred, blowing a hole inthe top of the trailer and leaking chemical on the ground. The driver unhooked and pulled thetractor away from the trailer and called for assistance. When the fire department and hazardousmaterials team arrived, they were informed that three 55-gallon drums containing a mixture ofzirconium oxynitrate and nitric acid had reacted and exploded.

Case Study 3

Employees at a manufacturing facility began to complain of a strong odor, as well as eye andskin irritation, when they entered an area of the plant. The odor was traced to an exterior areawhere several ammonia cylinders were stored. As the fumes spread over a wider area, employ-ees called the fire department.

Case Study 4

In Alabama, a pesticide plant was leveled by an explosion that released toxic fumes. Smallerexplosions continued over the next few hours. Fire fighters arrived and evacuated a 10-mileradius around the pesticide plant.



Case Study 5

A tractor-trailer in New York collided with a car and spilled 80 to 90 gallons of diesel fuel into astorm drain. The storm drain fed into a nearby creek, which eventually discharged into a river.Fire fighters and several well-equipped hazardous materials teams responded.

Case Study 6

In Texas, a train carrying a variety of hazardous materials was involved in an accident. Nine tankcars derailed and spilled 5,000 gallons of styrene monomer. Some of this product spilled into anearby creek. Fire fighters and civil defense personnel responded to the scene.



Manhattan Case Study Activity 2

Manhattan HazMat IncidentBy James J. Fay

NYPD First Precinct Detectives and FDNY Fire Marshals initiated an investigation into how 800pounds of highly explosive, highly toxic material were delivered to the doorstep of a lowerManhattan retail establishment.

On Sunday, November 26, at about 1515 EST, an initial response of NYPD Emergency ServiceUnits from ESU #1 and FDNY’s First Battalion, responded to 365 Canal Street, at West Broad-way, within the boundaries of NYC’s Soho District. The establishment, “American Liquidators”is a common type of retail store for the area, dealing in large quantities of electrical parts, armysurplus, and other items, piled on shelves and in bins throughout the store. The store personnelreported to arriving units that the four 33-gallon drums were delivered three days prior on Thurs-day, November 23, and left inside near the front door of the store. They also told police that theydid not order the product from any vendor, but were not initially concerned because of the highvolume of deliveries to the store.

Emergency personnel established from external markings on the drums that the containers heldwhat was best described as “aluminum powder.” With that information, NYC*EMS transmitteda ‘10-48’ haz-mat incident code, establishing a command post and the response of numerousBLS and Special Operations Division Units. Additional NYPD Emergency Service Units re-sponded, as well as the Police Bomb Squad and the FDNY Haz-Mat Company.

The normally gridlocked traffic in the area was made worse by the emergency equipment, neces-sitating response patterns being transmitted from the scene to incoming units.

The FD established its command post in its Haz-Mat unit, researching the source of the productback to its manufacturer via cell phone. The manufacturer acknowledged it was his product, buthad no information or knowledge of a delivery to that store. Haz-Mat also determined that thisaluminum powder was highly toxic to the skin and reacted with an explosion when it came incontact with water or other chemicals. All non-emergency personnel were instructed to remain150 feet from the product.

A NYC Department of Environmental Protection chemist arrived on the scene and requested thatsamples be taken from each drum. During this procedure, FDNY Haz-Mat fire fighters neededto change their half-hour SCBA bottles at least once while opening the tight drums and takingsamples.

A Fire Department unit equipped with “over-pack” drums responded to remove the material to aprivate vendor for proper disposal.



Approximately four hours after the first response, the scene was secured. Police and Marshalswould continue the investigation to find out if it was a simple mistake that put the dangerouscargo there or a malicious act.

© Emergency Response & Research Institute, 1995, All Rights Reserved

Questions

1. Refer to your NIOSH Pocket Guide and list additional hazards of aluminum powder.

2. If you had a leaking container of aluminum powder, how would you patch/plug and overpackit using the supplies in your own department?

3. What precautions should you take when patching/plugging and overpacking?

4. In this incident, fire fighters took samples from the drum. Are you equipped and trained totake samples? If so, describe how this procedure is done.



Cargo Tank Leak Activity 3

A semiconductor manufacturer (the shipper) hired a cargo tank from a chemical waste manage-ment company (the carrier) to transport a waste acid mixture to a disposal site some distanceaway. Because the carrier and shipper had done business in the past, the carrier’s dispatcherassigned the same type of cargo tank that had been previously used for that shipper.

When the driver arrived at the shipper’s location, mixed acid waste from two storage locationswas loaded into the cargo tank. The shipping papers described the cargo as “waste, acid liquidn.o.s.” (UN 1760). While in transit, the driver had mechanical difficulties and was directed to goto the nearest truck dealer for repairs. The driver parked the cargo tank in the dealer’s back lotand detached it from the tractor. Shortly thereafter, employees at the dealership noticed orangevapors escaping from the tank. However, no one notified the fire department until two hourslater.

When the fire department finally arrived, fire fighters evacuated the area and attempted to iden-tify the components of the mixed acid waste. The shipper and the carrier provided conflictinginformation as to the specific chemicals in the mixture. Meanwhile, vapors continued to escapefrom the tank, and the tank shell became very hot. Although the vapors and the tank temperaturewere reduced with a water spray, the acid mixture eventually eroded the shell and began to drain.

Questions

1. What can you do when you have conflicting information about a chemical, particularlychemical mixtures?

2. What control actions would you take?

3. How could the situation have been prevented?



Pressure Cargo Tank Activity 4

In small groups, read the incident information below and review the Westville map. Select oneperson to record the answers on the worksheet and report them to the class.

Incident Facts—Westville, USA

Environmental Factors

Weather Report: Clear. Temperature 85°F., winds from the south, 6-8 miles per hour

Proximity of the incident site to the nearest building: 200 feet

Zoning: Heavy industrial/commercial

Potential exposure area: 1400 hours, Wednesday

Other considerations: Storm drain openings nearby

Container

Type: MC331 Transport Truck with 10,000 gallon capacity

Condition of container: Internal liquid fill valve damaged and flowing 10 GPM of liquid propane

Features of container: Single shell uninsulated pressure vessel

Type of Flammable Gas Involved

Propane (LPG)

Properties: Heavier than air (VD = 1.52)Odorized gasLiquid outside container will drop to -44°FLPG is nontoxic but is an asphyxiant

DOT Information: ID# 1075



Worksheet

1. Discuss the incident and assess the threat that this flammable gas poses.

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

2. Recommend spill control strategies.

______________________________________________________________________________

______________________________________________________________________________

______________________________________________________________________________

3. On the Westville map, indicate where you would establish the following areas:

• Hot Zone• Warm Zone• Cold Zone• Decontamination Area• Incident Command



Maysville Case Study Activity 5

The Associated Press January 1988

A fire swept through a fertilizer plant Sunday forcing thousands of people on both sides of theOhio River to evacuate their homes as tons of potentially explosive chemicals burned.The Cargill Co. plant contained stockpiles of herbicides and pesticides and 420 tons of ammo-nium nitrate-a fertilizer used in making the bomb that destroyed the federal building in Okla-homa City. Authorities said there was a risk of explosion at the plant as the ammonium nitrateburned.

“It’s a volatile substance in the state it’s in now with fire,” said Roy Raby, an assistant State FireMarshal. The fire broke out about 2:30 a.m. and emergency crews went door-to-door wakingpeople within a square-mile of the plant advising them to take shelter at area schools. About2,500 people left their homes in Maysville and across the river in Brown and Adams counties insouthern Ohio.

Battling Blaze FutileAuthorities were letting the fire burn itself out, and a huge column of light gray smoke billowedfrom the plant. The fire was expected to destroy the plant by afternoon. Light wind drifted thesmoke northward into Ohio. Loretta Wills, who lives in an apartment complex near the plant,said she had to leave so quickly she put her slacks on backwards, and a neighbor left without herdentures. “We just had to grab and go,” she said.

The fire shut down a nearby CSX rail line and closed the Ohio River between Maysville andManchester, Ohio, about 10 miles upriver. There was no production at the plant when the firebroke out. Officials thought propane cylinders were the source.

A volunteer chief was hit by shrapnel after one explosion, said Steve Zweigart, local deputycoordinator for the state Division of Disaster and Emergency Services. The shrapnel did notpenetrate the skin and the fire fighter was treated at a local hospital and released, he said.

Cause InvestigatedFire investigators were on the scene trying to determine a cause of the fire. Maysville CityManager Dennis Redmond said the fire engulfed a building that stored several different fertilizersand chemicals, including the ammonium nitrate.

“By allowing the fire to burn, the pesticides and herbicides have been able to completely com-bust, which pretty much gets rid of the toxic effect of those chemicals,” Zweigart said.“The ammonium nitrate stockpiles posed the chief threat,” Zweigart said.

But Raby, the assistant State Fire Marshal, said, “This is not an Oklahoma City situation.”An explosive mix of ammonium nitrate fertilizer and fuel oil was detonated outside the federalbuilding in Oklahoma City in April 19,1995. The blast killed 168 people. Unlike Oklahoma



City, there was no accelerant, such as the fuel oil mixed with the ammonium nitrate at theMaysville plant, authorities said. Another difference was the ammonium nitrate was not con-tained but was burning freely at the plant, they said.

The State Fire Marshal’s office feared that applying water or foam to the blaze would create hugevapor clouds that would spread to more populated areas, Redmond said. Authorities also worriedabout potential runoff of chemicals into the Ohio River if they fought the fire, he said. The plantis about 600 yards from the river.

“The reality is it’s a matter of picking the lesser of two evils,” Redmond said. “The burning ofthese chemicals in the atmosphere does have a negative effect on the environment. But thateffect is less than the vapor clouds.”

Raby said anther reason for letting the fire burn was the more intense the heat, the higher thesmoke would drift into the atmosphere.

Copyright 1997, The Associated Press. All rights reserved. This material may not be published, broadcast, rewrit-ten, or redistributed.

Questions

1. This case study illustrates that sometimes the best action is no action at all. Would controlactions have been possible at any point in this incident? If so, when? What actions wouldyou have taken?

2. At what point do you determine that control actions are not possible?

3. Discuss other potential situations at facilities in your area in which no action wouldbe the best action.



Appendix B

MiscellaneousMitigation Information



Response Actions

Analyze the Problem

• Determine the presence of hazardous materials1. Review dispatch information2. Note the occupancy or location3. Look for container shapes and sizes4. Look for placards, labels or markings5. Review shipping papers

• Initiate command and control activities1. Implement an incident command system2. Stage at a safe distance3. Control access and shelter in place/evacuate

• Survey the incident1. Determine the type of container2. Identify container markings3. Determine the amount of hazardous material in the containers4. List the name of each hazardous material involved5. Identify which materials are released, their form, and the point of release6. Sketch the position and orientation of each container involved

• Collect information on each material’s hazards, physical and chemical characteristics, andresponse recommendations1. Obtain and record data on each material’s chemical, physical, and health hazards2. Obtain and record overall potential hazards3. Determine compatibility if multiple chemicals are involved4. Determine decontamination requirements5. Consult data resources

• Evaluate the extent of damage to the container1. Determine the construction material of the container2. Identify the type and location of closures3. Determine the type, location, and extent of damage

• Predict the likely behavior of the container without intervention1. Identify the type of stress or potential stress2. Predict the way the container is likely to breach3. Predict the way the contents are likely to be released4. Predict the dispersion pattern5. Predict the likely exposures and length of contact6. Identify the hazards that will cause harm7. Predict the most likely behavior of the release



• Estimate the potential outcomes within the release area1. Predict the extent of physical, chemical, and health hazards under current conditions2. Estimate the potential outcomes by type of harm within the affected area



Reproduced from Introduction to Hazardous Material Incident Response, developed byUnion Pacific Railroad Company and the United States Environmental Protection AgencyRegion VII, revised February 1991)



Hazardous Materials Data Sheet

Name of Hazardous Material _________________________________________________ (Proper Shipping Name)

Hazard Class ____________ (1-9) UN/NA ___ ___ ___ ___ Description _____________

__________________________________________________________________________

Specific Properties -- Physical, Chemical, Health: NFPA 704

Boiling Point_______F Flash Point_____F Ignition Temp______F

Flammable Limits LEL_________% to UEL_________% pH____(1-14)

PEL____ppm/mg/m3 TLV/Ceiling____ppm/mg/m3 IDLH____ppm/mg/m3 STEL____ppm/mg/m3

Physical State Vapor Density Specific Gravity

____Solid ____Heavier than Air (>1) ____Floats on Water

____Liquid ____Lighter than Air (<1) _____Sinks in Water

____Gas ____Equal to Air (1)

Water Soluble ___Yes ___No Emits Radiation ___Alpha ___Beta ___Gamma

Overall Potential Hazards Subjectively (1-4 where 1= low and 4= high potential hazard)

___Fire ___Highly Poison.....BY...... ____Inhalation

___Explosive ___Moderately Poisonous.....BY...... ____Absorption

___BLEVE ____Slightly Poisonous.....BY...... ____Ingestion

___Toxic Combustion

___Gas cloud Potential ____Highly Reactive ____________________

___Leak Hazard ____Moderately Reactive...WITH... ____________________

___Corrosive ____Slightly Reactive ____________________

___Radioactive Water ____Yes ____No

___Extreme Cold COMPLETE COMPATIBILITY MATRIX FOR MULTIPLE CHEMICALS

Type of Packaging _______________________________________________________________

Amount of Product _______________________________________________________________

Shelter in Place ___Yes ___No Evacuation/Isolation ____ feet in all directions initially (min.50 feet)

Follow-up ____feet/wide ____feet/miles downwind

Hot Zone at ___feet Warm Zone at ____feet Cold Zone at____feet

Required Protective clothing___Structural _____Level A* _____Level B ______High Temp. _____Cryogenic___Tyvek-Saranex _____Butyl _____PVC ______Neoprene _____Polyurethane____OTHER__________________________________________________________________________________



Possible Extinguishing/Neutralizing Agents or Materials:

____Water _____AFFF ____AFFF/ATC ______Dry Powder (Class D) _____Halon

____Dry Chemical (Acidic (ABC) or Alkaline) ____Vapor Suppression

Neutralizing Agents: ____Acid ____Alkaline _____Solvents

Absorbent/Adsorption Materials: ____Booms _____Pillows ____Rolls ____Sheets

_____Mats ____Granules ____Particulates _____Rags (cotton)

DECONTAMINATION REQUIREMENTS:

Decon Solution Decon Chemicals

____A. 5% Sodium Carbonate and 5% Trisodium Phosphate

____B. 10% Calcium Hypochlorite

____C. 5% Trisodium Phosphate

____D. Hydrochloric Acid

____E. Detergent

____F. Dry

____G. Water

DATA RESOURCE:

____CSIS ____Local Emergency Response Plan

____MSDS ____D.O.T. Emergency Response Guidebooks

____SUI ____Emergency Handling of Hazardous Materials

____Label ____in Surface Transportation

____NIOSH Pocket Guide ____Emergency Action Guidelines

____ACGIH -- TLV’s ____CHRIS

____SAX ____Rapid Guide to chemical Hazards in the Workplace

____CHEMTREC 1-800-424-9300

____NATIONAL RESPONSE ____NFPA Fire Protection Guide on Hazardous MaterialsCenter 1-800-424-8802

____Manufacturer ____Fire Dept./Local Emergency Planning Commission

____Technical Assistant by__________________________________________________________________________________

________________________________________________________________________________________________________



Plan the Response

• Determine response options that could favorably change the outcomes1. Identify the stage of release (stress, breach, release, engulf, contact or harm)2. Determine response objectives and strategies3. Determine tactics

• Identify appropriate personal protective equipment for the response options1. Verify the chemical2. Predict the types of exposures with each response option3. Determine the level of protective equipment required4. Identify chemically compatible PPE materials5. Determine if available PPE is sufficient

• Identify a decontamination plan1. Identify the people and equipment that must be decontaminated2. Determine the likely amount of contamination3. Research the appropriate decontamination materials

• Select the best response option1. Identify the resources needed2. Determine the availability of resources3. Determine how to obtain necessary resources

• Implement the response



Appendix C

Osceola, FL Fungicide Incident



Osceola, FL Fungicide Incident

The incident began on March 23 at 0300. A pickup truck crossed the centerline of State Road192 about 40 miles east of Walt Disney World in rural Florida. The pickup ran head-on into awestbound tractor-trailer truck. The accident resulted in a fire that destroyed both trucks andkilled the driver of the pickup. The tractor-trailer was not a typical box trailer, but an intermodalbox placed on the frame of a trailer. This is common in an area where ships import goods fromEuropean and South American countries. This intermodal box was made of heavy gauge steel.They are usually air and watertight.

When the Holopaw Fire Department unit arrived from approximately 2.5 miles away, the truckswere heavily involved in fire, with flames impinging onto the intermodal trailer. The next unitwas 15 miles away responding from a neighboring community in Osceola County. Holopaw FireDepartment is a small, one station, volunteer department that is part of Osceola County FireDepartment. (Osceola County FD is a mixed paid/volunteer department.) The first fire apparatusstaged about 15 feet from the burning trucks and used the on-board tank to extinguish the fire.After extinguishing the burning trucks, the trailer was opened to check for extension. A smallamount of smoke was noted toward the top of the trailer, so the response was upgraded to in-clude additional fire suppression units and Orange County’s Squad 1 (Orange County’s Haz MatUnit).

Referencing the chemical was immediately difficult because the shipping papers burned duringthe initial truck fire. Furthermore, the trailer was placarded with Class 9, Miscellaneous plac-ards, displaying the DOT #1609, which did not appear in the NAERG. Within a short time, thesestick-on style plastic placards melted from the trailer and were no longer readable. However, thetractor-trailer driver suffered only minor injuries during the crash, and was able to give theresponders the name of the shipper, who was eventually contacted by phone.

The shipper provided the name Diethane, which was later found to be an incorrect spelling.Diethane could not be found in the reference sources, so that even after this initial contact, theon-scene personnel did not have information to guide them during the incident. It was not untilthe MSDS was faxed to their headquarters station and transported to the scene that good informa-tion was at hand. The MSDS revealed the name Dithane DF Fungicide. The truck contained 772bags of dry chemical on pallets, or 38,000 pounds of dithane. The chemical dithane is producedin France and entered Florida at Port Everglades. Rohm Haas, the company importing thechemical, manufactures the precursor chemicals for this compound, then brings the finishedproduct back to the U.S. for distribution. Because of the recent flooding in the state, the onlywest-to-east road open across the state was SR 192. This was an unusual route for this materialto take, and an unfamiliar road to the driver.

By the time the data sheet arrived, the units on the scene had attempted extinguishment withwater. The water appeared to initially work, but each application was followed by freeburningfire from the rear of the trailer. It was also noted that the drops of concentrated runoff created abubbling effect when dropped on the roadway. Later, AFFF foam was used with the same re-sults.



The Rohm Haas hazmat team responded to the scene to assist Osceola County with the extin-guishment and cleanup of the chemical. Once on the scene, the Rohm Haas team fired thecleanup company initially under contract with them and received permission to hire a companywith the proper capabilities to deal with a spill of this magnitude. This was a day-long process.By this time, the fire had burned for three days with no end in sight and SR 192 remained closed.

The next plan for extinguishment included dumping two 450-pound cylinders of carbon dioxideinto the box. This was done on the fourth night. Although the intensity of the smoke decreased,it was obvious that the fire continued to burn. The final plan was to flow water nonstop into thetrailer until the fire went out. After thousands of gallons, the fire was finally extinguished.Runoff gathered in the roadside canal and marsh area.

The trailer was eventually towed to a yard in Tampa, where the remaining material was off-loaded and disposed of. The contaminated soil was, for the most part, excavated and disposed of.(It was reported that at least 29 tractor-trailer dirt haulers were used.) Even now, several monthsafter the incident, the vegetation in the area is dead or dying, with the accident site plainly visiblefrom the road.

The fire burned for a total of five days, and SR 192 remained closed for six days. The long-termeffects from possible exposure to the smoke have not been determined. Reference materialsindicate that combustion of this material gives off toxic levels of hydrogen sulfide, carbon disul-fide, sulfur oxides, nitrogen oxides, and carbon oxides.



Appendix D

Slide Script

(for Instructors)

module 9: control techniques - iaff main module 09 student text.pdf · b. hot tapping c. cold...

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