...
An air contaminant is any substance that is accidentally or unintentionally introduced into the air, having the effect of rendering the air toxic or harmful to some degree.
Scope
OSHA’s requirements protect employees from occupational exposure to air contaminants. The regulation applies to all workers who may be subjected to workplace air contaminants. The regulation lists various substances along with permissible exposure limits (PELs).
Did you know?
You do not have to handle a container of hazardous chemicals to be concerned with exposure to air contaminants. For example, idling vehicles emit engine exhaust that contains hazardous carbon monoxide. OSHA has a permissible exposure limit of 50 parts per million as an eight-hour time-weighted average for exposure to carbon monoxide. An employer must ensure employees are not overexposed to carbon monoxide if there is engine exhaust present.
Did you know?
Healthcare employee exposure to hazardous chemicals may include pesticides, disinfectants, and hazardous drugs in the workplace. While OSHA does not have specific standard for every healthcare contaminant, the Agency may use the General Duty Clause of the OSH Act to hold employers responsible for protecting workers.
Did you know?
Over 23 percent of surveyed warehousing and storage industry employees were regularly exposed to vapors, gas, dust, or fumes at work twice a week or more during the previous 12 months. Source: 2010 National Health Interview Survey sponsored by NIOSH.
Regulatory citations
- 29 CFR 1910.1000 — Air contaminants, including Tables Z-1 (Limits for Air Contaminants), Z-2 (Toxic and Hazardous Substances), and Z-3 (Mineral Dusts)
Compliance point
Because the organic material in tobacco doesn’t burn completely, cigarette smoke contains more than 4,700 chemical compounds. Although OSHA has no regulation that addresses environmental tobacco smoke (ETS) as a whole, the Air Contaminants Standard at 29 CFR 1910.1000 limits employee exposure to several of the main chemical components found in tobacco smoke. However, OSHA indicates that in normal situations, exposures would not exceed these permissible exposure limits (PELs), and, as a matter of prosecutorial discretion, OSHA will not apply the General Duty Clause (Section 5(a)(1) of the OSH Act) to ETS. Source: OSHA Policy on Indoor Air Quality: Office Temperature/Humidity and Environmental Tobacco Smoke, February 24, 2003.
Key definitions
- Acceptable ceiling concentrations: The standard’s Table Z-2 sets acceptable ceiling concentrations for many substances. An employee’s exposure to these substances may not exceed at any time during an 8-hour shift the acceptable ceiling concentration limit given for the substance in the table.
- Acceptable maximum peak above the acceptable ceiling concentration for an 8-hour shift: For some substances, the standard’s Table Z-2 allows an exception to the acceptable ceiling concentration requirements. An employee’s exposure may exceed a substance’s acceptable ceiling concentration if Table Z-2 lists an acceptable maximum peak above the acceptable ceiling concentration for an 8-hour shift. This maximum peak concentration is only allowed for the maximum duration as shown in the table.
- Ceiling values: In the standard’s Table Z-1, some substances show a “C” in front of the chemical’s exposure limit. This means that an employee’s exposure may at no time exceed the substance’s exposure limit. If instantaneous monitoring is not feasible, then the ceiling is to be assessed as a 15-minute time weighted average exposure that is not to be exceeded at any time during the working day.
- Dusts: Are tiny particles that are dispersed into the air (i.e., silica, wood dust, etc.).
- Gases: Are elements or compounds that are normally in the gaseous state at ambient temperatures and pressures (i.e., chlorine, carbon monoxide).
- Fumes: are tiny particles that become suspended in the air, especially during welding or cutting operations (i.e., zinc fumes).
- Milligrams per cubic meter (mg/m3): means the weight of the contaminant (in milligrams) in one cubic meter of air.
- Millions of particles per cubic foot of air (Mppcf): is a measurement used for mineral dusts. These exposure limit measurements are based on impinger samples counted by light-field techniques.
- Mists: are tiny droplets of a liquid that has been atomized and dispersed into the air (i.e., paint sprays).
- Parts per million (ppm): means the number of equivalent parts of the contaminant per one million parts of air. For example, if the concentration of acetone is 50 ppm, there are 50 molecules of acetone per one million molecules of air.
- PELs, or Permissible Exposure Limits: Establish the acceptable amount or concentration of a substance in the air in the workplace. They are intended to protect workers from adverse health effects related to hazardous chemical exposure.
- Skin designation: If Table Z-1 shows an “X” in a substance’s entry in the column marked “skin designation,” that means the substance is able to absorb through the skin to contribute to an employee’s exposure.
- Vapors: are created when volatile liquids evaporate into the air (i.e., gasoline vapor).
Summary of requirements
Employers must:
- Determine the types and amounts of air contaminants in the workplace.
- Control sources of air contamination by using engineering controls, or, if necessary, by using personal protective equipment (PPE).
- Inform employees of what air contaminants are in the workplace and how they can protect themselves from them.
- Discuss any necessary PPE with workers and demonstrate proper use, cleaning, and storage of the equipment.
- Periodically test the air in the facility for the presence of air contaminants (as conditions warrant).