Pilot Study of Aromatic Hydrocarbon Adsorption Characteristics of Disposable Filtering Facepiece Respirators that Contain Activated Carbon

Abstract

Disposable filtering facepiece respirators (FFRs) used by health care workers are not designed to reduce the inhalation of volatile organic compounds (VOCs). Smoke-generating surgical procedures release VOCs and have been associated with the following complaints: foul smell, headaches, nausea, irritated throat and lungs, and asthma. Organic vapor FFRs that contain activated carbon are used by industrial workers to provide odor relief. These respirators remove irritating odors but are not marketed as respirators that provide respiratory protection against a gas or vapor. This study investigated the aromatic hydrocarbon adsorption capabilities of nuisance organic vapor (OV) FFRs. Three OV FFR models were tested to determine the 10% breakthrough time of three aromatic hydrocarbons at ambient room temperature and relative humidity. All respirator models were exposed to each vapor separately in three duplicate tests (n = 27). The respirator was sealed with silicone to an AVON-ISI headform that was placed in a chamber and exposed to VOC-laden air (20 ppm, 37 L/min). Periodically, gas samples were directed to an SRI gas chromatograph (Model 8610C) for analysis. All respirators performed similarly. The average 10% breakthrough values for all tests were at least 64 min, 96 min, and 110 min for benzene, toluene, and xylene, respectively. Respirators were tested with challenge concentrations at nuisance levels (20 ppm) and did not exceed 10% breakthrough values for at least 61 min. While the results of this pilot study hold promise, there is a need for further investigation and validation to determine the effectiveness of nuisance FFRs in mitigating organic vapors such as benzene, toluene, and xylene.

Keywords:

• organic vapors
• personal protective equipment
• respirator
• surgical smoke

Acknowledgments

The findings and conclusions in this article are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.