Figure 1: Classifications

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The Bloodborne Pathogens Standard and Disinfection

By Tom Bach


The OSHA Bloodborne Pathogens Standard (29CFR 1910.1030) is designed to protect employees from contracting a bloodborne disease during the performance of their normal job duties.

Hepatits B Virus (HBV) and Human Immunodeficiency Virus (HIV) are two significant bloodborne pathogens that are of concern to healthcare staff when using a hospital disinfectant to clean up a blood or other potentially infectious material (OPIM) spill according to the OSHA Bloodborne Pathogens Standard (29CFR 1910.1030) or when evaluating an appropriate liquid chemical germicide (LCG) to high-level disinfect heat-sensitive medical devices.

This OSHA Standard, originally published in the Federal Register on December 6, 1991, with an effective date of March 6, 1992, is designed to protect employees from contracting a bloodborne disease during the performance of their normal job duties. Due to the broad definitions within the standard, by design, workers that may come in contact with these body fluids may include police officers, first-aid responders, dental personnel, laboratory technicians, funeral directors, nurses, and GI personnel. This list is by no means all-inclusive. This Federal Standard1 covers numerous compliance subjects including, but not limited to, the following:

  • Definition of the standard
  • Definitions of the numerous terms used within the standard
  • Requirements of a written Exposure Control Plan
  • Exposure determination
  • Initial and annual follow-up training requirements
  • HBV vaccination
  • Engineering controls, i.e., sharps containers
  • Definition of occupational exposure
  • Housekeeping and decontamination requirements
  • Record keeping requirements

Although issued more than eight years ago, this standard continues to involve numerous man-hours by many business entities to maintain proper compliance with a standard whose goal is the protection of employees from contracting HBV or HIV via the normal performance of their job.

To keep the standard current, OSHA has revised the Compliance Directive (November 5, 1999) to the original standard that includes some key revisions. These revisions include the following:

  1. Annual review of the employer's Exposure Control Plan--allows for improvements to protect employees by using safer medical devices.
  2. Engineering Controls and Work Practices--stresses the use of effective controls to include safer devices, improved work practices, and more efficient personal protective equipment.
  3. Multi-Employer Worksites--focuses on healthcare employment agencies.
  4. HBV Vaccinations--adds the latest CDC guidelines on vaccinations, post-exposure evaluation, and follow-up.
  5. Training--stresses effective training, including "interactive" training rather than static review of films or videos.

Occupational exposure can result from any number of sources including human, environmental surfaces, medical devices, and related equipment. Human-to-human exposure is reduced through a common sense approach to Universal Precautions.2 Although Body Substance Isolation is noted within the standard, most professionals follow Universal Precautions including gloves, gowns, and face protection.

Universal Precautions mandate personal protection against disease based on the premise that all human body fluids and all patients are assumed to be contaminated.

Engineering controls include appropriately placed sharps containers, biohazard identification, segregation, and handling. Additional controls include isolation area ventilation requirements, regulated waste containers, handwashing facilities, and appropriate gloves, gowns, and face protection. Again, this list is not all-inclusive, and the only means of understanding this comprehensive standard is to take the necessary time to read it thoroughly. Housekeeping applies to any person who is cleaning up a blood or OPIM spill and the procedures required to ensure that a surface to be cleaned and decontaminated is essentially free of infectious contaminants. Whether cleaning ER surfaces or decontaminating a flexible endoscope, the principal of rendering the surface free of organic soil and related infectious organisms is the same.

Within a large hospital, the list of employees that must be covered under the standard can be enormous. With the exception of training requirements specific to any one department, the general training and offering of the HBV vaccine is the same. It is the specific handling of medical devices, equipment, linens, etc., that can result in variations to the written Exposure Control Plans that must be prepared.

A copy of the complete standard can be obtained by contacting the local OSHA office. The listings can be found in any phone book under the US Government heading, Department of Labor.

Because of the threat of HBV and HIV transmission in blood, healthcare professionals are looking for information and guidance regarding the proper treatment of instruments and surfaces to ensure that these pathogens and others are inactivated.

Currently, there are no readily available practical methods for testing a disinfectant against HBV since this organism cannot be grown in a typical lab culture. No methods currently exist for evaluation of a disinfectant against HCV. HIV is considered to be very fragile outside the human body and is relatively easy to inactivate by cleaning and disinfecting. The only approved method that exists to evaluate a disinfectant against HBV involves the use of live primates and puts these animals at risk for contracting hepatitis. The US Environmental Protection Agency (EPA) is currently evaluating methods that will use surrogate viruses, closely related to human HBV for predicting the efficacy of disinfectant products against this virus. These methods will be used to generate acceptable claims and will ultimately require validation to maintain these claims.

Although data have not yet been generated, based on practical scientific knowledge and the epidemiology of microorganisms, one can deduct that based upon a product's efficacy against higher organisms, as evident by the Spaulding Classification 3 (Figure 1), that it will effectively inactivate both HBV and HCV. This rationale is predicated upon efficacy data against Mycobacterium tuberculosis. Dr. Earle Spaulding of Temple University (Philadelphia, Pa), originally presented the Spaulding classification to the medical community in a 1939 paper on the disinfection of surgical instruments in a chemical solution. Due to his extensive study of disinfection and sterilization of medical instruments, Spaulding further refined his classification of appropriate treatment of medical devices based upon how a device is used. Chemical disinfection was classified as low level, high level, and sterilization based upon whether a device contacted intact skin, mucous membranes, or was introduced into the sterile cavity of the body.

According to scientific knowledge of a microorganism's resistance to disinfection, there is a hierarchy of susceptibility to the cidal effects of disinfectants. A disinfectant's strength must match the decontamination requirements of a medical device, depending on its contact with external or internal (sterile) parts of the body or for surfaces exposed to blood or OPIM under the OSHA Standard. This is the rationale for the Spaulding classification. Figure 2 represents the descending order of the susceptibility of various microorganisms to disinfection as associated with the Spaulding classification. It is important to note that HBV falls under low-level disinfection while TB falls under intermediate-level disinfection.

After much industry and end-user debate and confusion, OSHA provided clarification that narrowed the scope of products claiming HBV efficacy to cleaning surfaces known to be contaminated only with HBV and/or HIV (for example, as in a research setting).4 According to OSHA recommendations, "when bloodborne pathogens other than HBV or HIV are of concern, OSHA continues to require the use of EPA-registered tuberculocidal disinfectants." This letter of clarification relates to surface disinfection only and does not apply to cleaning and reprocessing medical devices.

Although this OSHA clarification addresses the use of disinfectants on environmental surfaces, the principal of a product's germicidal strength based on its ability to kill TB applies to both disinfectants regulated by EPA and liquid chemical germicides regulated by the FDA. Reprocessing a medical device involves both meticulous cleaning and high-level disinfection of many small intricate surfaces both internal and external. It is the combination of meticulous cleaning, rinsing, and drying followed by high-level disinfection that renders the device safe for reuse.5 Isn't it the goal of the Infection Control Practitioner as well as the GI Nurse, Reprocessing Technician, and Environmental Services Technician to ensure that the "surfaces" that the employees, patients, and visitors contact are appropriately cleaned and decontaminated?

Tom Bach is the Technical Service Manager for Reckitt Benckiser Professional, Reckitt Benckiser North America (Wayne, NJ). The company is the manufacturer of the Lysol IC and Professional Lysol Brands of Infection Control Products and programs that support clean and healthy environments.

References

1. Federal Register. Vol. 56, No. 235. Friday December 6, 1991, Part 1910.1030.(Amended).
2. Occupational Safety and Health Administration. Occupational exposure to bloodborne pathogens: final rule. Federal Register. 1991; 56:64003-182.
3. Alvarado CJ. Revisiting the Spaulding classification scheme. In: Chemical Germicides in Healthcare. William A. Rutala ed. Washington, DC: APIC; 1994:203-208.
4. McCull R. Occupational Safety & Health Administration. Health Compliance Assistance Office: Interpretation and Compliance Letters. The OSHA policy on the use of disinfectants that are registered with the EPA as being effective against HBV and HCV. September 24, 1996.
5. Society of Gastroenterology Nurses and Associates, Inc. Endoscope Cleaning and High-Level Disinfection, Self-Study Module. SGNA Practice Committee; 1996.


Figure 1: Classifications

Body Contact Disinfection Requirements FDA Device Class
intact skin low level non-critical
mucous membranes high level semi-critical
sterile body cavity sterilization critical

Figure 2: Microorganism's Resistance to Disinfection and Sterilization Associated with Disinfection Level Classification
High-Level Disinfection or Sterilization
Bacterial Spores
(Bacillis subtilis, Clostridium difficile)
Intermediate-Level Disinfection
Tubercle Bacilli
(Mycobacterium tuberculosis)
Nonlipid and Small Viruses
(Coxsackievirus, Hepatitis A Virus, Poliovirus, Rhinovirus)
Low-Level Disinfection
Fungi
(Aspergillus niger, Candida albicans, Trichophyton mentagrophytes)
Gram Positive & Gram Negative Vegetative Bacteria
(Pseudomonas aeruginosa, Salmonella choleraesuis, Staphylococcus aureus)
Lipid or Medium-Sized Viruses
(Cytomegalovirus, Hantavirus, Herpes Simplex Virus, Hepatitis B Virus, Human Immunodeficiency Virus-HIV 1, Respiratory Syncytial Virus)
Chart modified from Favero and Bond, 1991


For a complete list of references click here
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