Breathing Zone

What Does Breathing Zone Mean?

The breathing zone in a workplace is defined as the area closest to an employee's mouth and nostrils. The U.S. Occupational Safety and Hazard Administration (OSHA) defines the breathing zone as the area within a ten-inch radius of the worker's face. When conducting air sampling to determine whether an employee will be exposed to airborne hazards in the workplace, personal air samples may be collected within the worker's breathing zone. These levels represented by the sampling are then compared to the permissible exposure levels (PEL) for the specified substance.

In many cases, this method of sampling is voluntary. However, for some substances, personal breathing zone sampling is mandatory pursuant to OSHA guidelines.

This breathing zone may also be referred to as a personal breathing zone.

WorkplaceTesting Explains Breathing Zone

To take samples from the breathing zone, employees may wear a monitoring device on their shirt collar or at another location near their nose and mouth. The air samples must be collected from the ambient air, not from inside any personal protective equipment, such as a respirator, worn by the worker.

The purpose of air sampling in a worker's breathing zone in the workplace is to ensure that employees are not exposed to dangerous levels of airborne contaminants such as dust, biological agents, or toxic chemicals. To assess whether or not an employee is at risk for exposure to these substances, sampling is sometimes taken within the employee's breathing zone. This zone is presumed to represent the air that the worker will breathe during the course of his or her work day.