Reducing Worker Exposures to Asphalt Fumes

Source: Sergejs Belovs - 123RF

According to NIOSH, when contractors apply hot asphalt on roofs, they are exposing themselves to a variety of illnesses, including headache, eye, nose, throat, and skin irritation, nausea, fatigue, and drowsiness.

These effects appear to be mild and transient. According to some studies, however, roofers also have an increased risk of lung cancer. But researchers are not sure whether this risk is caused by exposure to asphalt fumes or to other hazards such as smoking, coal tar, or asbestos.

In light of this possible health risk and the irritation effects associated with hot asphalt work, it makes sense to take steps to control exposures while government, industry, labor, and independent researchers continue to study these health concerns.

Efforts are underway to identify new engineering controls and to test their effectiveness in reducing fume exposures at the kettle.

To date, studies have shown that the use of fume-suppressing roofing asphalts can reduce fume exposure at the kettle. As these studies are completed, appropriate recommendations will be developed and disseminated.

NIOSH’s Guide to Reducing Roofers’ Exposure to Asphalt Fumes, respiratory protection may be needed if available engineering controls and work practices are ineffective in keeping asphalt fume exposures below the NIOSH recommended exposure limit of 5 mg/m3 (measured as a 15-min ceiling) or applicable State or Federal standards.

However, because respirator use can introduce significant new safety hazards in roofing work, respirator use should be the last resort for controlling exposures.

If respirators are required at the work site, the employer or contractor must make sure that they are NIOSH-approved and that all applicable OSHA regulations that apply to respirator programs are followed. Important elements of these OSHA regulations are as follows:

• An evaluation of the worker’s ability to perform the work while wearing a respirator;

• Regular training of workers;

• Periodic environmental monitoring;

• Respirator fit-testing, maintenance, inspection, cleaning, and storage;

• Periodic changing of cartridges and testing for service life No NIOSH-approved respirator filter cartridge or canister exists specifically for asphalt fumes.

But the respirators listed below will reduce exposures:

• Any half-facepiece, air-purifying respirator equipped with a combination R100 or P100 filter and an OV (organic vapor) cartridge; and

• Any powered, air-purifying respirator with hood, helmet, or loose-fitting facepiece equipped with a combination HEPA and OV cartridge.

NIOSH is working together with industry and labor representatives to find methods that will significantly reduce asphalt fume exposures for roofers and contractors.