Decontamination biological safety cabinets

At 70—140°C, peroxide is vaporised. Peroxide vapor has been reported to rapidly inactivate pathogenic bacteria, yeast, and bacterial spores in very low concentrations (133). Experiments using peroxide vapor for space decontamination of rooms and biologic safety cabinets hold promise (134). The use of peroxide vapor and a plasma generated by radio frequency energy releasing free radicals, ions, excited atoms, and excited molecules in a sterilising chamber has been patented (135). 

Formaldehyde Decontamination of the Laminar Flow Biological Safety Cabinet, (slide/cassette) NAC no. 005137 and no. 003148, National Audio Visual Center (GSA), Washington, D.C., 1976. 

Jones, R., Drake, J., and Eagleson, D., Using Hydrogen Peroxide Vapor to Decontaminate Biological Safety Cabinets. Acumen, Baker Co, 1.1, Sanford, ME, 1993. 

Protections include engineering controls, such as biological safety cabinets, controlled access and airlocks, ventilation systems, showers, decontamination facilities, and potentially separate buildings. There are also administrative controls, such as protection from needle and other punctures and cuts ( sharps ), written manuals for operations, and other procedures. There are recommendations for personal protective equipment (PPE) for each BSL. 

After completion of the run, wipe with a disinfectant all surfaces that have been exposed to the agent. If the lyophilizer is equipped with a removable sample chamber, close off the chamber and move it to a biological safety cabinet for unloading and decontamination. Try to minimize handling of cultures, and utilize vapor traps wherever possible. 

These techniques should only be carried out by experienced persons to avoid accidental release of noxious as well as toxic chemical vapors into occupied areas. Different procedures are used to decontaminate laboratories, high efficiency particulate air (HEPA) filter plenums, and biological safety cabinets. These procedures are listed below. 

Figure 5.5 Cabinet decontamination. Preparing a biological safety cabinet for decontamination.

A troublesome problem in any laboratory is the disinfection and/or decontamination of an overt biological spill. A spill poses a smaUer problem if it occurs in a biological safety cabinet, provided it does not splatter to the outside of the cabinet. Direct application of concentrated liquid disinfectant and a thorough... 

Blenders, homogenizers, mechanical pipet-ters, etc. must be used inside biological safety cabinets. Aerosols must be allowed to settle after use of this equipment, and the equipment and area must be decontaminated as required when the operation is finished. Pipetting can produce as much as 1.5 X 10 droplets (10 micrometers or less in diameter) per cubic centimeter. (Droplets of this size can be inhaled.)... 

We will consider the two different types of spills mentioned above spills in the open, and spills in the biological safety cabinet. As a rule, spills in the open are more disruptive to laboratory operation since the laboratory must be evacuated until decontamination is completed, while spills in the biological safety cabinet, if the spill is completely contained within the cabinet, involve much less disruption of laboratory activities. 

All workers using the biological safety cabinet with potentially infectious agents should have a supply of an appropriate decontaminant located within the cabinet. This avoids the need to withdraw the arms from the cabinet should a spill occur. If the arms or hands have been splashed with culture material, pour the decontaminant onto them without withdrawing them from the cabinet. 

The use of H2O2 sterilization in biological safety cabinets and barrier isolators is a popular alternative to ethylene oxide (EtO) as a safer, more efficient decontamination method. H2O2 has long been widely used in the pharmaceutical industry. In aerospace research, H2O2 is used to sterilize artificial satellites and space probes. 

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