STELs, also known as Short-term Exposure Limits, refer to the maximum allowable concentration of airborne substances that workers can be exposed to over a short period, typically 15 minutes, without suffering adverse health effects. STELs are established to protect workers from acute or immediate health risks associated with exposure to certain hazardous substances.
These limits are often set for substances that may cause irritation, discomfort, or immediate health effects, but may not have long-term effects at lower levels of exposure. STELs are defined separately from other occupational exposure limits, such as the permissible exposure limit (PEL), which refers to the maximum allowable concentration over an 8-hour workday.
The purpose of STELs is to prevent acute health effects that may occur due to brief but intense exposure to hazardous substances. By restricting and monitoring workers' exposure, STELs help prevent immediate harm and ensure workplace safety. They are typically indicated as a specific concentration of the substance in parts per million (ppm) or milligrams per cubic meter (mg/m³).
Furthermore, it is important for employers to regularly monitor and assess workplace conditions to ensure compliance with STELs and protect workers' health and safety. Adequate ventilation systems, personal protective equipment, and proper handling and storage procedures are among the measures that can be implemented to control and minimize exposure to substances that have established STELs.
