Formaldehyde is a colorless, strong smelling gas often found in water based solutions. Commonly used as a preservative in medical laboratories and mortuaries, formaldehyde is also found in many products such as chemicals, particle board, household products, glues, permanent press fabrics, paper product coatings, fiberboard and plywood. It is also widely used as an industrial fungicide, germicide and disinfectant. Mineral wool insulation contains 1% to 4% formaldehyde used as a binder.
Although the term formaldehyde describes various mixtures of formaldehyde, water and alcohol, the term “formalin” is used to describe a saturated solution of formaldehyde dissolved in water, typically with another agent, most commonly methanol, added to stabilize the solution. Formalin is typically 37% formaldehyde by weight and 6 to 13% methanol by volume of water. The formaldehyde component provides the disinfectant effects of formalin.
The OSHA Formaldehyde standard (29 CFR 1910.1048) and equivalent regulations in states with OSHA approved state plans protects workers exposed to formaldehyde and apply to all occupational exposures to formaldehyde from formaldehyde gas, its solutions and materials that release formaldehyde. The permissible exposure limit (PEL) for formaldehyde in the workplace is 0.75 parts formaldehyde per million parts of air (0.75 ppm) measured over an 8 hour time weighted average (TWA). The standard includes a second PEL in the form of a short term exposure limit (STEL) of 2 ppm which is the maximum exposure allowed during a 15 minute period. The action level, which is the standard’s trigger for increased industrial hygiene monitoring and initiation of worker medical surveillance is 0.5 ppm when calculated as an 8 hour TWA. Gribbins Insulation Company has conducted industrial hygiene sampling on employees working with formaldehyde with results ranging from less than 0.01 ppm to 0.05 ppm.
Formaldehyde is a sensitizing agent that can cause an immune system response upon initial exposure. It is also a cancer hazard. Acute exposure is highly irritating to the eyes, nose and throat and can make anyone exposed cough and wheeze. Subsequent exposure may cause severe allergic reactions to the skin, eyes and respiratory tract. Ingestion of formaldehyde can be fatal and long term exposure to low levels in the air or on the skin can cause asthma like respiratory problems and skin irritation such as dermatitis and itching. Concentrations of 100 ppm are immediately dangerous to life and health. Workers can inhale formaldehyde as a gas or vapor or absorb it through the skin as a liquid. They can be exposed during the treatment of textiles and the production of resins. Airborne concentrations of formaldehyde above 0.1 ppm can cause irritation to the respiratory tract. The severity of irritation intensifies as concentrations increase.
Provision of the OSHA standard requires employers to do the following:
- Indentify all workers who may be exposed to formaldehyde at or above the action level or STEL through initial monitoring and determine their exposure.
- Reassign workers who suffer significant adverse effects from exposure to jobs with significantly less or no exposure until their condition improves. Reassignment may continue for up to 6 months until the worker is determined to be able to return to the original job or to be unable to return to work, whichever comes first.
- Implement feasible engineering and work practice controls to reduce and maintain worker exposure to formaldehyde at or below the 8 hour TWA and the STEL. If these controls cannot reduce exposure to or below the PELs, employers must provide workers with respirators.
- Label all mixtures or solutions composed of greater than 0.1% formaldehyde and materials capable of releasing formaldehyde into the air at concentrations reaching or exceeding 0.1 ppm. For all materials capable of releasing formaldehyde at levels above 0.5 ppm during normal use, the label must contain the words “potential cancer hazard.”
- Train all workers exposed to formaldehyde concentrations of 0.1 ppm or greater at the time of initial job assignment and whenever a new exposure to formaldehyde is introduced into the work area. Repeat training annually.
- Select, provide and maintain appropriate personal protective equipment. Ensure that workers use PPE such as impervious clothing, gloves, aprons and chemical splash goggles to prevent skin and eye contact.
- Provide showers and eyewash stations if splashing is likely.
- Provide medical surveillance for all workers exposed to formaldehyde at concentrations at or above the action level or exceeding the STEL, for those who develop signs and symptoms of overexposure, and for all workers exposed to formaldehyde in emergencies.