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Mission-Specific Competencies: Product Control

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Objectives (1 of 4)

• Describe and identify the control options available to operations level responders

• Describe and identify the control options available for flammable liquid and flammable gas incidents

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Objectives (2 of 4)

• Describe purpose, equipment, precautions associated with control options

• Describe the applicability and characteristics of aqueous film-forming foam, alcohol-resistant concentrates, fluoroprotein foams, protein foams, and high-expansion foams

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Objectives (3 of 4)

• Identify the location and describe the use of emergency remote shut-off devices on MC/DOT-306/406, MC/DOT-307/407, and MC-331 cargo tanks containing flammable liquids or gases

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Objectives (4 of 4)

• Describe the recovery phase, and the transition from emergency to clean-up

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Confinement

• Keeps hazardous material within area of release

• Done by– Damming– Diking– Confining vapors

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Containment

• Stops material from leaking from container

• Examples– Patching container– Righting overturned container

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Control Options

• Solution must be quick and safe

• Should minimize negative effects on– People– Property– Environment

• Use risk-based thought process

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Sometimes No Action Is Safest Course (1 of 2)

• Create safe perimeter– Be aware of natural control points

• Let problem stabilize on its own

• Protect exposures

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Sometimes No Action Is Safest Course (2 of 2)

Sometimes it is necessary to let the problem stabilize on its own.

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Absorption (1 of 5)

• Absorbent material soaks up liquid release– Vermiculite– Clay– Peat moss– Spill pads

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Absorption (2 of 5)

Spill pads are often used to soak up a liquid hazardous material.

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Absorption (3 of 5)

• Effective only on flat surfaces

• Disposal of used material is necessary

• Requires close proximity to spill

• Adds volume to spill

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Absorption (4 of 5)

• Some materials repel water while absorbing spilled liquid

• Useful to contain oil spill on body of water

• Spill booms used on water or land

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Absorption (5 of 5)

A spill boom can be used to confine a liquid.

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Adsorption

• Contaminant adheres to surface of material– Silica– Activated carbon

• Can generate heat

• Functions like Velcro—sticks to product

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Damming

• Used when liquid flows in channel

• Progress is stopped by blocking channel

• Three kinds of dam– Complete dam– Overflow dam– Underflow dam

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Complete Dam

• Placed across small stream or ditch

• Completely stops flow of material

• Used for – Basically dry stream or ditch– Small amount of hazardous material

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Overflow Dam (1 of 2)

• Contains materials heavier than water

• Pipe through dam allows water flow

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Overflow Dam (2 of 2)

An overflow dam is used to contain materials that are heavier than water.

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Underflow Dam (1 of 2)

• Contains materials lighter than water

• Pipe through dam allows water flow

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Underflow Dam (2 of 2)

An underflow dam is used to contain materials that are lighter than water.

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Diking

• Barrier, keeps hazardous material in place

• Materials used– Sand– Dirt– Loose absorbent– Concrete

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Dilution

• Addition of water or another substance

• Weakens strength of hazardous material

• Typically used for corrosives

• Increases volume– May overwhelm containment measures

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Diversion (1 of 2)

• Redirects flow from endangered area– Existing curbs– Curvature of roadway– Dirt berms– Spill booms– Plastic tarps filled with sand, dirt, or clay

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Diversion (2 of 2)

Diversion methods are not as “permanent” as a dike, and they can be constructed fairly quickly.

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Retention• Creates defined area to hold material

• Example: Digging a hole– Allows material to collect or pool

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Remote Valve Shut-off

• Pre-existing shutdown device in system

• Found in– Chemical processes– Piped systems that carry chemicals– Cargo tanks

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MC-306/DOT-406 Cargo Tank (1 of 2)

• Carries flammable liquids, explosives, poisons

• Has various safety features

• Has remote shut-off valve

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MC-306/DOT-406 Cargo Tank (2 of 2)

The remote shut-off valve is typically found near the front of the cab, adjacent to the driver’s door, or at the rear of an

MC-306/DOT-406 cargo tank.

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MC-307/DOT-407 Cargo Tank (1 of 2)

• Carries low-pressure chemicals– Flammables– Combustible liquids– Mild corrosives – Poisons

• Has remote shut-off valve

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MC-307/DOT-407 Cargo Tank (2 of 2)

The remote shut-off valve is typically found near the front of the cab, adjacent to the driver’s door, or at the rear of an

MC-307/DOT-407 cargo tank.

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MC-331 Cargo Tank (1 of 2)

• Carries compressed liquefied gases– Anhydrous ammonia– Propane– Butane– Liquefied petroleum gas (LPG)

• Has remote shut-off valves

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MC-331 Cargo Tank (2 of 2)

The MC-331 cargo tank has remote shut-off valves at both ends of the tank, internal shut-off valves, a rotary gauge depicting

product pressure, and two top-mounted vents.

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Vapor Dispersion

• Spreads vapors out

• Thereby lowers their concentration

• Hose streams

• Fans

• Other ventilation systems

• Consequences should be considered

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Vapor Suppression

• Controls fumes given off by materials

• Particularly for flammable liquids

• Example: Gasoline

• Uses blanket of foam

• Reducing temperature may also suppress vapor

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Foams Used in Vapor Suppression

• Aqueous film-forming foam (AFFF)

• Alcohol-resistant concentrates

• Fluoroprotein foam

• Protein foam

• High-expansion foam

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Applying Foam (1 of 4)

• Several ways to apply foam– Bounce-off method– Rain-down method– Roll-in method

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Applying Foam (2 of 4)

The bounce-off method.

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Applying Foam (3 of 4)

The rain-down method.

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Applying Foam (4 of 4)

The roll-in method.

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Recovery Phase (1 of 3)

• Danger has passed or is controlled– Danger to people– Danger to property– Danger to the environment

• Clean-up begins

• Can be lengthy in large-scale incidents

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Recovery Phase (2 of 3)

The recovery phase involves clean-up, determination of the responsible party, and implementation of cost recovery.

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Recovery Phase (3 of 3)

• Initial responders may also perform clean-up

• Commercial companies may perform clean-up

• Returns exposure area to original condition

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Summary (1 of 2)

• Various factors must be evaluated to choose a control option

• Sometimes safe perimeter can be created and the problem left to stabilize on its own

• Control techniques contain, redirect, or lower concentration of hazardous material

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Summary (2 of 2)

• Options include absorption, diversion, damming, diking, shut-off valves, special foams

• Recovery phase returns exposure area to original condition

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