OSHA requirements are set by statute, standards and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website at https://www.osha.gov.

November 13, 1998

Ms. Tonya A. Garreaud
Unit 61317 Box R132
APO, AE 09803-1317

Dear Ms. Garreaud:

Thank you for your correspondence of September 5, requesting information regarding specific substances which were used in your medical facility. Please accept my apology for the delay in this response.

You requested information regarding signs and symptoms which may follow inhalation of the substances hydroquinone, acetic acid, and glutaraldehyde. Hydroquinone and acetic acid are potentially hazardous substances which are regulated by the Occupational Safety and Health Administration (OSHA), in accordance with the Air Contaminant Standards, 29 CFR 1910.1000. Glutaraldehyde, on the other hand, is a substance that is not currently regulated by OSHA.

We understand that you are a civilian working for a private corporation overseas. Please note that the information provided is not enforceable or regulated in your situation and may only be used as a guideline. On foreign soil, these guidelines are applicable only to civilian and Federal employees on a military base, and not to employees of a private corporation.

According to OSHA regulations, the permissible exposure limit (PEL) for hydroquinone is 2 milligrams per cubic meter of air (mg/m3) as measured over an 8-hour period, otherwise known as an 8-hour time weighted average, TWA. A short term acute exposure to hydroquinone may cause a variety of symptoms including, but not limited to, headaches, dizziness, nausea, and difficulty breathing. Acetic acid has an OSHA PEL of 10 parts per million (ppm) or 25 mg/m3 as an 8-hour TWA. Some symptoms of acetic acid vapor exposure are redness, runny nose, sore throat, coughing and other symptoms. Even though there is not an OSHA PEL for glutaraldehyde, the American Conference of Government Industrial Hygienists (ACGIH) has a recommended ceiling Threshold Limit Value (TLV). The recommended TLV for glutaraldehyde vapor from either activated or unactivated solutions is 0.2 ppm. This TLV is based on the irritation threshold in humans. Glutaraldehyde is a strong irritant to the nose, eyes, and skin and occasional or occupational exposure can cause skin sensitization.

You also asked if there are ways to determine the levels of certain substances in the area. The airborne concentrations of substances may be determined by several sampling methods. To screen for substances, portable monitors, gravimetric sampling or detector tubes may be used depending of the substance. Vapor badges are also useful for screening certain chemical exposures.

The National Institute for Occupational Safety and Health (NIOSH) is OSHA's sister agency and conducts research into occupational exposures to hazardous substances. NIOSH is under the Department of Health and Human Services and is an agency of the Center for Disease Control.

NIOSH develops recommendations concerning new or improved occupational safety and health standards. Therefore, NIOSH may be able to provide you with further information regarding potentially toxic substances. You may contact NIOSH by calling 1-800-35-NIOSH or, if you have access to the Internet, by visiting their web page: www.cdc.gov/niosh. For your further information, OSHA's home page on the Internet can be found at: www.osha.gov.

Enclosed are copies of Occupational Safety and Health Guidelines for Chemical Hazards for both hydroquinone and acetic acid, which have been produced by NIOSH. These guidelines provide available information on these substances and include information such as routes of exposure, signs and symptoms of exposure, monitoring and measurement procedures, emergency procedures, and respiratory protection.

We appreciate the opportunity to provide you with this information. If you require further assistance, please do not hesitate to contact OSHA's Office of Health Compliance Assistance at 202-219-8036.


Richard E. Fairfax
Acting Director
Directorate of Compliance Programs