produce a 0.53% hypochlorite solution. Use of bleach solutions with lower hypochlorite concentrations might not provide the proper level of disinfection. Each day, prepare a fresh 1:10 household bleach solution (3, 23).
B. Alcohols. Alcohols generally act by coagulating proteins and as organic solvents. Rapid evaporation may lead to inadequate “killing” time. Although there are some conflicting reports, 70% solutions generally have the best microbicidal activity. Caution is advised because of flammability. DO NOT USE ALCOHOLS OR ALCOHOL-BASED SOLUTIONS ALONE TO DISINFECT SURFACE AREAS; EVAPORATION SUBSTANTIALLY DECREASES EFFICACY.
C. Another option can be seen in Fig. 11.3.
Note Use disinfectants recommended for environmental surfaces, such as Environmental Protection Agency (EPA)-registered disinfectants effective against hepatitis B virus, human immunodeficiency virus (HIV), and other blood-borne pathogens, or use a 1:10 dilution of household bleach. EPA environmental disinfectant product registration information is available at http://www.epa.gov/oppad001/chemregindex.htm (accessed 9/11/2013).
2. Immediate actions
A. Clear the area at once.
B. Notify the supervisor and chief of microbiology.
C. Assess the type of spill and degree of hazard involved.
D. Determine the most effective and least hazardous approach to clean up and decontaminate.
3. “Dry spills” with no significant aerosol formation
A. Flood the area with disinfectant solution.
B. Soak up disinfectant and contaminated material with absorbent material (sand or paper towels), and dispose of it in a plastic biohazard bag or sealed container. Wear gloves for cleanup.
C. If routine cleanup is not possible, the unit may have to be decontaminated with a sterilizing gas such as paraformaldehyde.
D. Thoroughly wash the unit (if possible) after decontamination.
4. Liquid spills on the bench or floor
A. If significant aerosols were formed, the area should be evacuated and not reentered for at least 1 h.
B. Flood the area with disinfectant, and cover the spill with absorbent material (sand or paper towels). Wear gloves during cleanup.
C. Dispose of absorbent and contaminated material in plastic bags or sealed containers, and autoclave.
D. Thoroughly wash the area after cleanup.
5. Centrifuge spills
A. Shut off the instrument, and evacuate the area at once.
B. Do not reenter the area for at least 1 h until aerosols have settled.
C. The person entering the area to clean up should wear protective clothing, gloves, and a mask.
D. If liquids are present, soak up in absorbent material and handle as above. If liquids are not present, clean the instrument and room thoroughly before resuming work.
E. Wipe all surfaces with a recommended disinfectant.
6. Spills in incubators, autoclaves, or other closed areas
A. Flood with disinfectants, and soak up liquids with absorbent material.
B. Dispose of the material as specified above, if possible.
C. If routine cleanup is not possible, the unit may have to be decontaminated with a sterilizing gas such as paraformaldehyde.
D. Thoroughly wash the unit (if possible) after decontamination.
Disposal of Contaminated Materials (3, 24)
1. Autoclave screw-cap tubes before cleaning or discarding.
2. Discard specimens and cultures into containers with double plastic lining. Liners should be changed when the containers are about half full.
3. Place culture plates into “Biohazard” receptacles lined with autoclavable bags.
4. Materials or containers to be reused should be autoclaved before being cleaned. Place them in sealed and clearly labeled containers to minimize hazard to others before sterilization.
5. Any breakage of glass or leakage of contaminated materials should be reported to the supervisor or chief of microbiology at once for instructions on procedures for safe cleanup.
All laboratories should adhere to the concept of standard precautions, which state that all patients and all laboratory specimens are potentially infectious and should be handled accordingly (8, 24–26). This concept arose from the observation that infections are often unrecognized in patients. “Standard precautions” replaces earlier terms such as Blood and Body Fluid Precautions, Universal Precautions, and Body Substance Precautions found in OSHA documents (8, 26). The OSHA documents place the emphasis on blood-borne pathogens such as HIV and hepatitis B and C viruses, whereas the concept of standard precautions recognizes that all infectious agents and all other potentially infectious material, except sweat, pose a risk to the health care worker (8).
OSHA identifies a number of practices that should be implemented to protect the worker from exposure to blood-borne pathogens, including an exposure control and risk assessment plan (7). Methods should be implemented to minimize exposure to infectious agents, to shield the laboratory worker from infectious material through a set of engineering and work practice controls, and to use personal protective equipment. In addition, the OSHA regulations require that employers provide hepatitis B vaccination and postexposure evaluation and follow-up; communicate the hazards to employees; and maintain appropriate records (8). Employees who decline immunization against hepatitis B virus are required to sign a hepatitis B vaccine declination form.
Note Under circumstances in which differentiation between body fluid types is difficult or impossible, all body fluids shall be considered potentially infectious.
1. All job positions with any exposure to blood and body fluids must be listed on an exposure form, which must match up with continuing education training records from the facility.
A.
