Industrial Hygiene Sampling: Exposure Testing and Monitoring
Industrial Hygiene Sampling and Analysis
Exposure to hazardous chemicals in the workplace can give rise to acute and chronic health effects. To ensure a safe and healthful workplace, there are regulatory standards found in the California Code of Regulations (CCR) Title 8 that are enforced by the California Occupational Safety and Health Administration (Cal/OSHA). In accordance with the regulations, an employer is responsible for identifying and measuring exposures in the workplace so that all employees can be properly protected. Air sampling should be conducted whenever there is reason to believe that workers may be exposed to concentrations above the allowed limit. The first line of defense is typically elimination or substitution of harmful constituents, but in many places that may not be possible, or the substitution may introduce a new hazard. In those cases, engineering controls can be implemented. However, such controls are not always enough to protect the workers. Administrative controls can then be implemented followed by personal protective equipment (PPE).
Workplace Exposure Monitoring
Yorke Engineering, LLC provides on-site evaluations and air sampling services to determine if employees are overexposed to harmful substances at work. Depending on the site-specific circumstances, personal and area air sampling can be done with active or passive monitors, direct-reading instruments, or by analysis at a laboratory. Our team of Certified Industrial Hygienists (CIHs) and Certified Safety Professionals (CSPs) will review safety data sheets, collaborate with American Industrial Hygiene Association (AIHA)-certified laboratories, and use our professional judgement and experience to develop a customized scope of work for your facility to determine if employees are exposed above permissible or recommended levels. We will use the analytical results, in combination with our observations of work processes and site conditions, to develop recommendations for corrective actions that will lead to a safer and healthier work environment. Yorke can also assist with developing and reviewing health and safety programs, as well as providing advice on the selection of PPE.
Yorke’s team has helped numerous clients with exposure monitoring for contaminants, including but not limited to:
- Department of Industrial Relations Table AC1 – permissible exposure limits for chemical contaminants.
- Total and respirable dust – this includes particulates of various sizes that are not regulated under a substance specific standard. Exposure can occur from woodworking, grinding, cutting and sanding.
- Welding fumes including hexavalent chromium – metals and alloys used in pipes, framing, etc. that need to be joined together via welding can cause the metals to be released. Some of the metals of concern include cadmium, beryllium and chromium.
- Respirable crystalline silica – found in stone, concrete and mortar and used to make glass, ceramics, bricks. Exposure can occur from abrasive blasting, cutting stone countertops, and drilling in concrete.
- Lead – found in batteries, ammunition, paint, solder to name a few. Exposure can occur from recycling batteries, shooting, remodeling, and manufacturing processes involving soldering.
Regulatory and Recommended Limits
Airborne exposures are covered under 8 CCR Section 5155 Airborne Contaminants. In order to protect workers, there are several types of Cal/OSHA regulatory limits: permissible exposure limits (PELs), Action Levels (ALs), Ceiling (C) limits, and short-term exposure limits (STELs). PELs and Als are expressed as 8-hour time-weighted averages (TWAs) for a standard 8-hour workday and 40-hour workweek, to which nearly all workers may be repeatedly exposed, day after day, without adverse health effects. STELs refer to concentrations to which workers can be exposed for a short period of time without suffering from irritation, chronic, or irreversible tissue damage or narcosis of sufficient degree to increase the likelihood of accidental injury, impair self-rescue, or materially reduce work efficiency. The STEL often supplements the TWA where there are recognized acute effects from a substance whose toxic effects are primarily of a chronic nature. Ceiling limits should never be exceeded, even for brief periods. There are also substance specific standards for contaminants with unusual nature or toxicity, like carcinogens for example.
In addition to regulatory limits, there are also recommended guidelines published by the American Conference of Governmental Industrial Hygienists. These limits are called threshold limit values (TLVs) that are often more stringent than regulatory levels and therefore offer better protection.