Washington University – St. Louis

Environmental Health & Safety

Indoor Air Quality

Strategies for investigating indoor air quality problems are very straightforward in that information is gathered

and conclusions are drawn based on findings. In the absences of specific contaminant sources or obvious

ventilation problems, EH&S will try to characterize the scope of the problem and systematically identify or

eliminate elements which are specifically associated with IAQ episodes. Outlined below is the process you

should expect from a campus IAQ investigation.

I. Initial contact—An EH&S staff person will speak, either in person or telephone, with someone

familiar with the problem, usually the affected person(s), or their supervisor to identify specific concerns (i.e. comfort, odors, health, ventilation)

II. Walk Through Investigation—An initial, walk-through investigation is conducted by EH&S to identify immediately correctable causes or to develop a plan for conducting a more thorough investigation

III. Define Scope—Strategies are developed to evaluate suspected problems (e.g., ventilation system, chemical sources, microorganisms, or circulate questionnaires to better define the nature, scope, and exact location of the problem)

IV. Initial Monitoring—Preliminary air sampling is conducted. Normally it will involve the use of real time analyzers for carbon dioxide and other easy-to-measure air contaminants, or cursory testing with smoke tubes.

V. Involve Other Divisions—Building Services will assist in ventilation system evaluation and preventative maintenance. An occupational physician will be consulted for medical concerns. The insurance department will be contacted for workers’ compensation concerns

VI. Detailed Monitoring—Ventilation system testing and/or sampling for chemical and biological contaminants is conducted as warranted.

VII. Evaluate Findings—Conditions and monitoring results are compared to criteria established through standards, codes, guidelines and good practice.

VIII. Identify Solutions—The need for corrective actions and controls is identified, and solutions are recommended

IX. Correction—Controls and recommendations are implemented as necessary. X. Follow-up—Findings and results are communicated to concerned parties.

Initial (Phone) Questionnaire

Name?

Location? Symptoms? Is there an odor, if so what does it smell like? When did the symptoms/odor start? How often do you experience the symptoms/odors? When are the symptoms/odors most prevalent?

When do symptoms/odors go away (how long do they last)? Is there anyone else affected, if so where are they in the building relative to you? What do you think the source is? Do you have allergies (what are they)? Do you have asthma? Do you smoke? Have you noticed any events in the building (weather, temperature/humidity changes, activities in the building) that correspond with the symptoms/odors? Have you seen a doctor for your symptoms? What is the approximate size of the room you work in? How many others work in this room? Approximately how many hours a day do you spend in this room?

Indoor Air quality - Initial Walkthrough

I. Contact for assistance during the walk-through:

Building Maintenance Contact

Business Manager or Office Supervisor

Employee(s) complaining or with symptoms

II. At the Site of the problem or complaint:

Conduct interviews or distribute questionnaires

Check for obvious sources of the problem (improper pressure differences, mold growth, dust, odors,

temperature or humidity extremes etc.).

Check temperature, humidity, carbon dioxide and carbon monoxide levels using the Q-Trak.

III. Check the HVAC Systems:

Outdoor Air Intakes

- Location of intakes

- Position of damper (open or closed)

- Location of exhaust

- Contaminant sources nearby

Ductwork

- Intact, connected

- Dry

- Clean

Supply Air Diffusers

- Position: open or closed

- Distribution of air (too much, too little)

- Location in the room

- Clean

Return Air or exhaust Grills

- Location in the room

- Position: open or closed

- Clean

Indoor Air Quality Survey

Some individuals working in this building have reported health complaints. To help investigate the possible

presence or absence of similar complaints this survey is being distributed to all or some occupants. Your

assistance is requested. Please complete this survey as accurately as possible.

1. Symptoms:

2. When do these symptoms occur?

3. How long have you had symptoms?

4. How often do symptoms occur?

5. When do you experience relief from these symptoms?

6. Is there a noticeable odor?

7. Have you noticed any events in or near the building (weather, temperature/humidity changes, construction

activities) that correspond with the symptoms?

8. Have you seen a physician for these symptoms?

9. Do you have any of the following?

_____Hay fever, pollen allergies _____Skin allergies/dermatitis

_____Sinus problems _____Cold/flu

_____Other allergies _____Asthma

10. What area do you primarily work in?

11. Approximately how many hours per day do you spend in this area?

12. Is there a history of indoor air quality issues that you are aware of in this area?

13. Briefly describe your primary job tasks.

14. Can you offer any other comments or observations concerning your office environment?

15. Your name and telephone number?

Symptoms Irritant Asphyxiant Anesthetic Systemic Airborne Temperature Humidity Light/Noise

Toxicant pathogen/

allergen

Eye irritation X X

Dry or sore throat X X

Skin irritation X X

Skin rash X

Tightness in chest X X X X

Runny nose X X

Asthma exacerbation X X X

Cough X X X X

Wheezing or other breathing X X X

Chest pain X X X

Changes in rate or depth of breathing X X X

Changes in pulse rate X X X X

Visual disturbances X X X X (noise)

Dizziness X X

Fatigue X X X X X

Depression X X X X

Clumsiness X X X

Drowsiness X X

Headache X X X

Fever X X

Repeated throat infections X

Sinus irritation X

Muscular pains X

Change in heart rhythm X

Tingling or numbness in extrimities X

Nausea or vomitting

Abdominal pain X (noise)

Diarrhea

Loss of appetite X

Cold/flu symptoms X X

Difficulty in sleeping X X

Irritablity X X X

Bachache/neckache X

Eye strain X

Indoor Air Quality

Dust/Particulates

Symptoms

Dry or sore throat

Runny nose

Skin irritation

Eye irritation

Excessive dust

Black “dust”

Exposure Limits

OSHA 29 CFR 1910.1000

Particulates (not otherwise regulated) Total Dust 15 mg/m3

Respirable fraction 10 mg/m3

EPA Outside Particulate Matter Standards PM 2.5 65 µg/m3

PM 10 15 µg/m3 Sampling

Sampling should only be conducted when there are the above symptoms reported For particulate sampling a pre-weighed filter cassettes with a PVC filter should be obtained from an outside laboratory. Using a personal sampling pump, sample at 4-5 L/m for 24 hours. Samples then should be brought to the same outside laboratory for analysis. Contact: Bill Lowry at EnviroHealth Technologies Inc. (314) 531-9868

FMD Assistance

The following should be completed before sampling is conducted: Custodial Services should dust area that has complaint initially

Building Services should check/change filters

Indoor Air Quality

Light

Symptoms

Headache/Backache/Neckache Fatigue Depression Drowsiness Eye Strain Irritability Difficulty Sleeping Exposure Limits

Refer to the following typical light levels for office work areas provided by Extech Instruments.

Lux Foot Candles Office Area 75 - 100 7 – 10 Indoor Emergency Stairs

100 - 200 10 - 20 Corridor Stairs 200 - 750 20 - 75 Conference, Reception Room

750 – 1,500 75 - 150 Clerical Work 1,500 – 2,000 150 – 200 Typing, Drafting

Sampling

Sampling may be conducted using the Heavy Duty Light Meter (Model 40726)

Solutions

Have custodial services or building services replace the light bulbs and/or ballasts

Consult with Building Services and/or outside contractors experienced with lighting

FMD Assistance

Building Services Electricians may assist by installing, removing and/or adjusting light fixtures

Indoor Air Quality

Mold/Fungi

Symptoms

Sore throat

Headache Cold-like symptoms

Exposure Limits

There are no strict numerical guidelines which are appropriate for assessing whether the contamination in an

area is acceptable or not. Further investigation of contamination sources is warranted in the following

circumstances.

1. Total indoor counts are greater than outdoor counts. This comparison is not valid when the

outdoor sample was taken immediately after precipitation. It is probably not valid during some winter months where outdoor fungal counts are usually below that of indoor counts.

2. Comparison of indoor and outdoor levels of fungal organisms show on of the following:

A. Organisms are present in the indoor samples that are not present in the outdoor sample. B. The predominant organism found in the indoor sample is different than the predominant

organism in the outdoor sample. 3. If either of the criteria from #2 are met and the organism is capable of producing toxins.

Sampling

Determine the temperature and relative humidity of the affected area. Relative humidity should be between 30-

60%.

Determine through visible inspection and/or interviews if there is or was water infiltration in the area. Run the Andersen single-stage sampler for 5 minutes in the affected area(s) and as close to the air intakes as

possible outdoors. If the outdoor temperature is below 30 degrees run a sample in an entryway or foyer. Do not

run comparison samples outdoors during or shortly after precipitation.

Plates should be delivered to Barnes microbiology as soon as possible after sampling.

Indoor Air Quality

On-going Diesel Odors

Symptoms 10 ppm may cause Fatigue 25 ppm for 24 hours may lead to visual impairment 50 ppm for 24 hours may lead to irregular heartbeat 500 ppm for 1 hour may lead to nausea, headache and mental confusion. 1500 ppm for one hour may lead to death. Sources

Tobacco Smoke, Malfunctioning heating equipment and vents, Motor vehicle exhaust, Internal combustion

engines

Exposure Limits

ACGIH - TLV USEPA ASHRAE 62-1989

CO 25 ppm – 8 hr. avg.

35 ppm 9ppm annual avg.

same as USEPA

CO2

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1000 ppm

Sampling

Use Q-Trak, Solutions

Dilution ventilation Remoting of air handling unit

Isolating vehicle carburetors Restricting smoking FMD Assistance

Call maintenance or design & construction personnel responsible for the building involved in IAQ investigation to get information on air handler location, HVAC and ductwork etc. Call maintenance supervisor(s) to notify the contractor using heavy diesel equipment that vehicle carburetors need to be isolated and turned off when not in use.

Indoor Air Quality

Ergonomics

Symptoms

Headaches Muscle pain Dry itchy eyes Blurred vision Tiredness Uncomfortable feeling Exposure Limits OSHA General Duty Clause Sampling Conduct an ergonomic evaluation FMD Assistance Custodial Services may be needed to replace burned out lights Building Services/In-house Renovation may be needed to add lighting, attach keyboard trays, adjust desk levels, etc.

Indoor Air Quality

Thermal Discomfort

Symptoms Headache Drowsiness Discomfort Sources Inadequate ventilation, blocked plenums, closed dampers, malfunctioning fan, radiant heat loss (windows) Exposure Limits

Relative Humidity Winter Temperature Summer Temperature 30% 68.5 F - 76.0 F 74.0 F - 80.0 F 40% 68.5 F - 75.5 F 73.5 F - 79.5 F 50% 68.5 F - 74.5 F 73.0 F - 79.0 F 60% 68.0 F - 74.0 F 72.5 F - 78.0 F

Source: Adapted from ASHRAE standard 55-1981, Thermal Environmental Conditions for Human

Occupancy.

Sampling

Use the Q-Trak

Solutions

Measure Indoor and outdoor temperature and humidity. Determine if extreme conditions exceed design

capacity of HVAC equipment

Measure Carbon Dioxide (CO2) in the complaint area to see whether it indicates ventilation problems. CO2

exceeding 1000 ppm may indicate poor ventilation

Check for drafts and stagnant areas

Check for excessive radiant heat gain or loss (i.e. where there are large or numerous windows)

Open, adjust, or repair air distribution system (supply, return) to see if air is moving (using chemical smoke)

Ensure proper air distribution:

Balance the air handling system

Make sure that there is an air gap at tops and bottoms of partitions to prevent dead air space

Relocate supply and/or return diffusers to improve air distribution

Seal leaky ductwork

Remove obstructions from return air plenums

Control pressure relationships

Move occupants closer to supply diffusers

FMD Assistance

Call maintenance personnel responsible for building involved in IAQ investigation to get information on air handler location, HVAC and ductwork etc.