Indoor Air Quality

There’s no OSHA standard for it. For the most part, you can’t see it or touch it. But, the potential risks are significant. We’re talking about indoor air quality (IAQ). What are the causes of unhealthful air? What are the effects on worker health and productivity? And, what can you do to reduce the risk?

What Is IAQ?
IAQ refers to the quality of the air inside buildings as represented by concentrations of pollutants and thermal conditions like temperature and humidity. These affect the health, comfort, and performance of people who work in those buildings.
According to the EPA, air quality problems are a result of conditions such as the:

  • Increase in chemical pollutants in consumer and commercial products
  • Tendency toward tighter buildings and reduced ventilation to save energy
  • Pressure to defer maintenance and other services in order to reduce costs

Air quality may be influenced by a building’s site, design, renovations, maintenance of air-handling systems, occupant density, activities conducted in the building, and the occupants’ satisfaction with their environment.

Many IAQ problems are associated with improperly operated and maintained heating, ventilation, and air-conditioning (HVAC) systems. Other contributors include moisture, radon, presence of outside pollutants, internal contaminants like cleaning and disinfecting supplies, and use of mechanical equipment.

Three Types of Pollutants
Indoor air pollutants fall into three basic categories: biological, chemical, and particle.

1. Biological pollutants include excessive concentrations of bacteria, viruses, fungi, dust mites, animal dander, and pollen. These can result from inadequate maintenance and housekeeping, water spills, inadequate humidity control, condensation, or water introduced through leaks in the building envelope or flooding.

2. Chemical pollutants are caused by emissions from products used in buildings. Examples are office equipment, furniture, wall and floor coverings, pesticides, and cleaning products. Other sources are accidental chemical spills, construction-related products, and gases that are by-products of combustion. Examples are carbon monoxide, formaldehyde, and nitrogen dioxide.

3. Particle pollutants are solid or liquid, non-biological substances light enough to be suspended in air. Among these are dust or dirt drawn in from the outside. Other particles are produced by activities that take place inside, such as construction, sanding, printing, copying, and operating equipment.

Eyes, Nose, Throat, and More
Health effects of poor IAQ vary widely and can be mistaken for symptoms of other conditions such as allergies, colds, the flu, and even stress. Among diseases linked to poor IAQ are asthma and hypersensitivity pneumonitis, an inflammation of the lungs.
Symptoms may include irritation of the eyes, nose, and throat; headache; dizziness; rashes; and muscle pain and fatigue. These typically disappear soon after exposure ends.

Chemicals released from building materials can cause headaches, and mold spores may result in itchy eyes and runny noses in sensitive individuals soon after exposure.

Cancer is the most commonly associated long-term health risk of exposure to indoor air contaminants. Long-term exposure to radon, asbestos, benzene, and tobacco smoke is linked to an increase in cancer risk.

How Protect Workers?
OSHA recommends a management approach to IAQ problems – the same systematic means that you might use to address other safety and health issues. The elements are familiar:

  • Management commitment
  • Training
  • Employee involvement
  • Hazard identification and control
  • Program audits

Management needs to be receptive to potential concerns and complaints and train workers on how to identify and report air quality concerns. If employees have issues, it’s the job of leaders to assess the situation and take corrective action.

Building owners and managers should develop and implement an IAQ management plan to address, prevent, and resolve problems. EPA recommends selecting an IAQ coordinator and policies, assessing the current status of indoor air quality through periodic inspections, performing necessary repairs and upgrades, and implementing follow-up assessments or other needed steps.

If you lease space, you should become familiar with the building management’s strategy for resolving IAQ problems. It’s important to know who to contact in buildings where there is mixed use and pollutants may come from a variety of sources. Leases should specify IAQ performance criteria, such as specific rates of ventilation.

OSHA recommends a team approach to solving problems and building consensus around indoor air. An IAQ team should include building occupants, administrative staff, facility operators, maintenance staff, healthcare staff, contract service providers, and other interested individuals.

Control Methods
There are four primary methods of reducing indoor air pollutants.

1. Source management. This is considered the most effective. It involves the removal, substitution, and enclosure of sources. An example is installing low-volatile organic compound (VOC) carpets. Another is establishing temporary barriers to contain pollutants during construction.

2. Engineering controls. An example is a local exhaust system such as a canopy hood that removes sources of pollutants before they can be dispersed into a building’s indoor air. A well-designed and functioning HVAC system controls temperature and humidity levels.

3. Administrative controls. These are management activities that keep employees from IAQ hazards. Among these is scheduling work to eliminate or reduce the amount of time an employee is exposed. For example, maintenance or cleaning should be scheduled when fewer building occupants are present.

4. Good housekeeping. Keeping the workplace clean can also help. Recommended practices include using mat systems that prevent dirt from entering the environment, disposing of garbage promptly, storing food properly, and choosing cleaning products that minimize pollutants.

Note: The above article is an edited version of two articles by Chris Kilbourne in the Safety Daily Advisor. Click on the article titles below to see the full articles:

IAQ: Protect Workers from Risk and Keep Them Comfortable
How Can You Protect Workers from IAQ Risks?