In response to a request from the Alliance for Polyurethanes Industry (API), OSHA confirmed that, in appropriate circumstances, air-purifying respirators (APR) are acceptable to protect workers from exposure to diisocyanates.
OSHA issued a similar response to a request on the same subject from 3M Co. earlier this week.
Under prior regulations and policies, OSHA required the use of supplied-air respirators to protect employees from excessive exposure to gases and vapors with poor odor warning properties, including the common diisocyanates, such as methylene bisphenyl isocyanate (MDI).
"Many workers in the polyurethane industry welcome the option of using air-purifying respirators because they provide adequate protection while improving mobility and visibility, and are more comfortable to wear than supplied-air respirators," said Fran Lichtenberg, API''s executive director.
API specifically asked OSHA what information an employer would need to consider in order to properly select an air-purifying respirator.
Richard Fairfax, director of OSHA''s Directorate of Compliance Programs, confirmed that APR may be used provided that:
- a complete respirator program meeting OSHA''s requirements is implemented;
- the respirator is equipped with an end-of-service life indicator (ESLI) certified by NIOSH for the contaminant;
- the employer has data to show that the APR will adequately protect the exposed employees; and
- if there is no ESLI appropriate for the chemical and conditions in the workplace, the employer implements a change schedule for canisters and cartridges that is based on objective data that will ensure that canisters and cartridges are changed before the end of their service life.
In his letter, Fairfax noted that currently there are few respirators available on the market with ESLI and none for MDI.
Therefore, an employer should select a cartridge or canister recommended by the manufacturer and must then implement an appropriate change schedule.
The data relied upon and the information forming the basis of the determination must be included in the employer''s written respirator program.
Fairfax emphasized the importance of having in place a comprehensive respiratory protection program.
API and its members are preparing materials to assist users in complying with OSHA''s new respiratory protection standard, including a model program and information designed to allow users to meet the requirements for using APR in their operations.
For more information on these materials go to API''s Web site at www.polyurethane.org.
by Virginia Sutcliffe