Disinfecting surfaces contaminated with blood

NOTICE: This is an OSHA Archive Document, and may no longer represent OSHA Policy. It is presented here as historical content, for research and review purposes only.

June 21, 1993

Ms. Rhoda George
Director of Environmental Services
West Park Hospital
[Recipient address omitted]
Dear Ms. George:

This is in response to your letter received May 12, regarding the Occupational Safety and Health Administration (OSHA) regulation 29 CFR 1910.1030, "Occupational Exposure to Bloodborne Pathogens." Specifically, you asked for an explanation of OSHA's requirement for the use of a tuberculocidal disinfectant to clean contaminated areas.

Your letter suggested that "physical removal of the source contamination is the best means of controlling the cross contamination." It is unclear exactly what is meant by "physical removal." However, even after rinsing or scrubbing, residual blood or other potentially infectious material (OPIM) likely remains on that surface, and the surface must therefore be decontaminated.

The use of protective coverings, such as plastic wrap, aluminum foil, or imperviously-backed absorbent paper is an acceptable alternative for protecting items and surfaces against contamination, provided that the coverings are removed and replaced as soon as feasible following overt contamination or at the end of a workshift if they may have become contaminated during the shift.

Your letter states that "there are no studies to show that any inanimate object was ever the cause of an infection or disease to be transmitted." While there is no documented evidence showing transmission of HIV from environmental surfaces, there is evidence that surface contamination is a mode of hepatitis transmission. Hepatitis transmission, especially type B hepatitis, can occur by indirect means via common environmental surfaces, such as test tubes, laboratory benches, other laboratory accessories, and any other surfaces contaminated with infectious blood, serum, secretions, or excretions which can be transferred to the skin or mucous membranes.

Dr. Steven Hadler of the Centers for Disease Control (CDC) Hepatitis Branch provided the following testimony during the rulemaking process:

"...Transmission of HBV from contaminated environmental surfaces has been shown to be a major mode of HBV spread in certain areas... The HBV can survive for at least one week in dried blood on environmental surfaces or contaminated needles and instruments."

Further, researchers have been unable to propagate HBV in culture, therefore extensive virucidal testing has not been performed. Consequently, little is known about the precise inactivation kinetics of HBV by physical or chemical agents. For this reason, OSHA requires the strength of a tuberculocidal disinfectant to ensure the health and safety of employees exposed to blood and OPIM.

You felt that "good housekeeping practices and the use of an EPA registered germicide for general cleaning" would be "just as efficient," and that tuberculocidal disinfectants should be used in "high risk areas" such as operating rooms and emergency rooms. The term "germicide" is a broad term which applies to a broad range of products with varying strengths, and the EPA does not have a category labeled simply "germicide." A disinfectant known to kill bloodborne pathogens is required for adequate cleaning. Because contaminated work surfaces present the same hazard regardless of where they are located in a facility, tuberculocidal disinfectants are required wherever there is contamination from blood or OPIM, regardless of the setting. However, quaternary ammonia products are appropriate for use in general housekeeping procedures which do not involve the clean-up of contaminated items or surfaces. Please bear in mind that the term "contaminated" is defined as the presence or reasonably anticipated presence of blood or OPIM.

Your letter also raised the concern of contact time. You are correct that a ten minute contact time with liquid chemicals is generally required to achieve high-level disinfection. You stated that in your hospital, however, you do not have that much time available, and "15 to 30 seconds is about the amount of time that any surface stays wet." Cleaning methods will vary according to many factors, including the level of disinfection required and the product being used. It is the employer's responsibility to determine appropriate disinfection methods. The employer should follow the manufacturer's instructions printed on the disinfectant's label.

As you may know, the state of Wyoming operates its own occupational safety and health program under a plan approved and monitored by the U.S. Department of Labor, pursuant to section 18 of the Occupational Safety and Health Act of 1970. State plan requirements may be more stringent than federal OSHA regulations. Should you wish to contact them, they may be reached at the following address:

Director Wyoming Occupational Health and Safety Herschler Building, 2nd Floor East 122 West 25 Street Cheyenne, WY 82002

We hope this information has been responsive to your concerns. Thank you for your interest in employee safety and health.

Sincerely,
Ruth McCully, Director
Office of Health Compliance Assistance

[Requester letter and earlier OSHA correspondence reproduced on OSHA page; omitted here.]