IMPORTANT: • Respirators and other personal protective equipment are
not exposure controls. Respirators may be used to protect employees while exposure controls are being installed or when it's not feasible to use exposure controls to remove or reduce the airborne hazard.
(1) Use feasible exposure controls to reduce employee exposure to one of the following:
– A level below the permissible exposure limits (PEL) in Table 3
– A level that removes the airborne hazard, when no PEL is established
– The lowest achievable level, when exposure cannot be reduced to below the PEL or the airborne hazard can't be removed.
(2) Make sure exposure controls don't create or increase employee health hazards. For example, when ventilation systems are installed:
– Prevent contaminated exhaust air from either:
▪ Reentering the building in harmful amounts
or
▪ Exposing any employee to a health hazard.
– Temper make-up air, when necessary
– Prevent employee exposure to excessive air velocities.
(3) Use make-up air systems that will not interfere with the effectiveness of the exhaust air system.
– For example, make sure enough make-up air is provided to replace the amount of air exhausted.
| Note: | • Table 1 provides examples of possible exposure controls. |
Table 1
Examples of Possible Controls
| Preferred exposure controls include: | For example: |
| Using a different chemical (this is also known as substitution) | • Choose a chemical with a lower evaporation rate or vapor pressure |
| | • Choose a chemical that's not hazardous |
| Changing a process to decrease emissions | • Use hand rolling or paint dipping instead of paint spraying |
| | • Bolt items instead of welding them |
| Separating employees from emissions areas and sources | • Use control rooms |
| • Build an enclosure around process machinery or other emissions sources |
| | • Automate a process |
| Using local exhaust ventilation to remove emissions at or near the source | • Install exhaust hoods or slots to capture emissions |
| | • Use an exhausted enclosure (like a blasting cabinet or laboratory hood) |
| Other exposure controls include: | For example: |
| Using general exhaust ventilation to dilute and remove emissions in the work area | • Allow natural air movement to create an adequate airflow through an area |
| Note: | • Use mechanical fans |
| This isn't recommended for control of highly toxic airborne contaminants such as carcinogens, where low exposures can still present a health hazard | |
| Modifying work practices | • Change the position of the employee relative to the work so fumes, vapors, or smoke aren't directed into the employee's face |
| Limiting the amount of time employees can spend in a contaminated area. | • Establish a contaminant-free area for tasks such as prep work that don't need to be done in the exposure area |
| Implementing an employee rotation schedule | Have employees alternate working in the exposure area so that each employee gets less overall exposure |
| Note: | |
| This control will increase the number of employees exposed to the airborne contaminant. Due to this risk, employee rotation is NOT recommended for highly toxic airborne contaminants such as carcinogens, where low exposures can still present a health hazard. | |
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, 49.17.060. 07-05-062, § 296-841-20010, filed 2/20/07, effective 4/1/07; 04-18-079, § 296-841-20010, filed 8/31/04, effective 11/1/04; 03-20-115, § 296-841-20010, filed 10/1/03, effective 1/1/04.]