Respiratory Protection During Fire Cleanup
After fires are extinguished and smoke has cleared, employees may be exposed to harmful substances in the air when cleaning or demolishing fire-damaged structures and areas. These harmful substances may include:
- Ash, soot and other byproducts of combustion disturbed during cleanup and demolition work.
- Dusts produced during cleanup and demolition work.
- Vapors released from damaged containers and pipes or from chemical products used in cleanup and demolition work.
- Gases released from damaged containers and pipes or produced by internal combustion engines, rotting materials, or other gas-generating processes.
Exposure to harmful substances in the air should be avoided or minimized by ventilating the area before and during work. If ventilation cannot be provided or is insufficient, employers must provide respiratory protection to protect the health of employees. (California Code of Regulations, Title 8, section 5144).
Identifying Respiratory Hazards
Before employees enter potentially harmful atmospheres, the employer must identify and evaluate the respiratory hazards. This evaluation must identify the chemical and physical properties of the contaminants in the air and reasonably estimate the levels of employee exposure. Where it is not possible to identify or reasonably estimate employee exposure, the atmosphere should be considered immediately dangerous to life and health (IDLH).1
Types of Respiratory Hazards:
Air contaminants can harm worker health. They exist in different physical forms:
- Particulates (such as dust) are fine solid particles suspended in air. Particulates are produced, for example, during cutting, grinding, crushing, milling and sanding.
- Mists are small liquid droplets suspended in air. Mist are produced, for example, during liquid spraying, machining with lubricants, and other types of mechanical agitation of liquids.
- Fumes are produced when solid materials are heated, evaporated, and condensed into very fine solids suspended in the air. This occurs, for example, during welding and torch cutting of metals and other materials.
- Vapors are substances in the gas phase at a temperature at which the same substance can also exist in a liquid state. For example, cleaning solvents commonly emit vapors when the container is opened and when applying the solvents onto a surface.
- Gases are the physical state of a material where the molecules move freely and are independent of each other. The other physical states are solid and liquid. Common toxic gases include carbon monoxide (created by internal combustion engines and fires) and hydrogen sulfide (created by rotting materials).
- Smoke is a collection of airborne particulates, mist, and gases produced when a material undergoes combustion.
In addition to contaminants in the air, lack of sufficient oxygen is potentially deadly.
Selecting the Correct Respirator
Respirators fall into two main categories, each designed to protect against specific respiratory hazards.
- Air-purifying respirators remove particulates, mists, fumes, gases, and vapors from the air using filters, cartridges, or canisters.
- Atmosphere-supplying respirators provide providing clean breathing air (from air tanks or air compressors) to the user rather than filtering out contaminants from the surrounding air.
The respirator selected must provide sufficient protection. The level of protection is called the respirator's assigned protection factor (APF). For example, a respirator with an APF of 10 can be used in an atmosphere where the air contaminant concentration is less than ten times the maximum exposure limit. The higher the APF, the more protective the respirator.
Employers must provide respirators approved by the National Institute for Occupational Safety and Health (NIOSH) and must ensure that employees are medically evaluated, fit tested, and trained before being required to use a respirator.
Air-purifying respirators can be used in atmospheres that have adequate oxygen, where the atmosphere is not considered IDLH and the concentration of contaminants does not exceed the protective capacity of the respirator. These respirators fall into two categories: those that remove particulates, mists, and fumes, and those that remove gases and vapors.
Particulate air-purifying respirators can be used for particulates, mists, or fumes, but not for gases or vapors. Particulate air-purifying respirators include the following:
- Filtering facepiece (dust mask) with two straps. This is a disposable respirator. It provides the lowest level of protection. With careful and limited use, filtering facepieces can protect against lower concentrations of airborne particulates, mists, and fumes. They do not protect against gases or vapors. They can generally be purchased in N-95 and N-100 versions. The N-100 versions provide greater protection. The "N" designation means that they are not resistant to the effects of oil mists. P and R versions are also available, which are more resistant to oil mists. For instructions on using filtering facepieces, see "Using Disposable Respirators" in English and Spanish.
- Half and full facepiece respirator with a particulate filter. This type of respirator is more protective
and longer lasting than disposable filtering facepieces, but it needs to be cleaned and maintained at least
daily. These respirators can be equipped with different types of filters, depending on the respiratory hazard.
For particulates, mists, or fumes, this respirator must be equipped with an N95, N99, N100, R95, P95, P99, P100,
or high efficiency particulate air (HEPA) filter.
- Half facepiece respirators have an APF of 10. Half-facepiece respirators are readily available (even at local hardware stores) and are easier to use than full-facepiece respirators.
- Full facepiece respirators have an APF of 50 and also protect the eyes from chemicals and debris.
- Both half and full facepiece respirators are available in models equipped with battery operated fans that make them cooler and less difficult to breathe through. These respirators are called powered air-purifying respirators (PAPR). The APF is 50 for a half-facepiece PAPR respirator and 100 to 10002 for a full-facepiece PAPR respirator.
Gas and vapor air-purifying respirators can be used for certain gases and vapors.
- Filtering facepiece respirators do not protect against gases or vapors.
- Half and full facepiece respirators can be equipped with cartridges that protect against
gases and vapors. The cartridge selected must be approved for the particular gas or vapor present.
The respirator will not provide protection if the wrong cartridge is used. See federal OSHA's
"General Respiratory Protection Guidance for Employers and Workers"
on selecting the correct cartridge. The most versatile cartridge available is a multiple
gas-and-vapor cartridge (designated by olive coloring) combined with a HEPA filter
(designated by magenta or pink coloring).
- Half facepiece respirators have an APF of 10. Half-facepiece respirators are readily available (even at local hardware stores) and are easier to use than a full facepiece respirator.
- Full facepiece have an APF of 50 and also protect the eyes from chemicals and debris.
- Both half and full facepiece respirators are available in models equipped with battery operated fans that make them cooler and less difficult to breathe through. These respirators are called powered air-purifying respirators (PAPR). The APF is 50 for a half-facepiece PAPR respirator and 100 to 1000ii for a full-facepiece PAPR respirator.
Atmosphere-supplying respirators must be used where:
- The atmosphere is considered IDLH because of a lack of sufficient oxygen or the presence of high concentrations of air contaminants.
- The concentration of contaminants exceeds the capacity of air-purifying respirators.
- Air-purifying respirators cannot protect against the particular gases or vapors present in the air.
Atmosphere-supplying respirators include the following types:
- Supplied-air respirators provide breathing air through an airline hose from a source outside the contaminated work area. The APF for a supplied air respirator ranges from 10 to 1,000.
- Self-contained breathing apparatus respirators provide breathing air from a compressed breathing air cylinder carried by the user. The APF for a self-contained breathing apparatus respirator ranges from 10 to 10,000.
Establishing a Respiratory Protection Program
Employers must ensure that respirators, when required, are used effectively and do not give the wearer a false sense of security or pose an additional hazard. Employers that give their workers respirators must have a written respiratory protection program that includes:
- Procedures for selecting the correct respirator.
- Medical evaluations of respirator users.
- Annual fit testing to ensure proper fit and no leakage.
- Procedures for proper use, maintenance, cleaning and replacement of respirators.
- For cartridge respirators, a cartridge change-out schedule to ensure that cartridges are replaced before the end of their service life unless the cartridge has an end-of-service-life indicator.
- Training of employees on the respiratory hazards to which they may be exposed, limitations of the respirators, and on the proper use of the respirators.
To ensure respirator effectiveness:
- VERY IMPORTANT: Workers must wear both straps, one around the back of the neck and the other around the crown of the head. Using only one of the straps will not allow the respirator to maintain a proper seal.
- Do not let hair, eyeglasses, or other objects interfere with the seal of the respirator to the face. No beards or facial hair: Workers must be clean-shaven for the respirator to seal properly.
- With half-mask and full facepiece respirators, employees must check for proper
function by doing a seal check before each use.
- First, cover the cartridges or filter and breathe in. The mask should be sucked against the face.
- Then cover the exhalation valve at the bottom of the mask and exhale lightly. There should be no major leakage and it should push away slightly from the face under positive pressure.
- Remember that respirators are not a substitute for proper control of hazards such as thorough wetting of dusts and provision of adequate ventilation when working with hazardous chemicals. However, particularly for short periods of use in situations where hazards may remain even after application of hazard control measures, respirators can provide important supplemental protection.
Where respirator use is not required by Cal/OSHA regulations or by the employer, the employer may provide respirators at the request of employees or permit employees to use their own respirators, if the employer determines that such respirator use will not in itself create a hazard. The employer must provide the respirator users with the information contained in Appendix D to section 5144 and must follow all other requirements in section 5144, subsection (c)(2).
Cal/OSHA Publication: Respiratory Protection in the Workplace: A Practical Guide for Small-Business Employers
Cal/OSHA Respiratory Protection standard: California Code of Regulations, Title 8, section 5144
Federal Occupational Safety and Health Administration (OSHA) webpage on respiratory protection
National Institute for Occupational Safety and Health (NIOSH) webpage on respirators
1Immediately dangerous to life or health (IDLH) means an atmosphere that poses an immediate threat to life, would cause irreversible adverse health effects, or would impair an individual's ability to escape from a dangerous atmosphere.
2An APF of greater than 100 can only be used when quantitative fit testing is used to assess the respirator fit on the user.