Autoclave waste decontamination

Any special equipment needed to maintain the required isolation for materials in the laboratory shall be provided. Examples are specially labeled waste containers, autoclaves, other decontamination equipment, or disposable clothing. 

The HIV and HBV research laboratories and production facilities must follow standard microbiological practices and specify additional practices intended to minimize exposures accessible to employees woridng with concentrated viruses. These practices also reduce the risk of accidental exposure for other employees at the facility. In turn, these facilities must include required containment equipment and an autoclave for decontamination of regulated waste, and they must be consteucted to limit risks and enable easy clean-up. Additional training and experience are required of workers in these ladlities. 

Autoclaving biohazardous waste requires some advance planning and knowledge of the characteristics of the autoclave, and recognition of the variables that accompany the use of autoclave bags (141, 261, 389). These factors, discussed below, should be kept in mind when using the autoclave for decontamination (393). 

After using toxins, wash every working surface with bleach, which is an efficient decontaminant. During the experiments, disposable materials should be used that can be eliminated as a biological hazard. As proteins, these toxins are heat labile and are completely inactivated by heating at 80°C for 10 min, i.e., conditions met by most standard decontamination treatments (heat autoclave) of medical infectious waste. 

All cultures, stocks, and contaminated wastes must be decontaminated before disposal by an approved method, such as autoclaving. Materials to be decontaminated outside of the laboratory must be placed in a durable, leakproof container and closed for transport from the laboratory. Materials to be decontaminated offsite must be packaged in accordance with any regulations applicable to transport of infectious materials before removal from the facility. 

Autoclaving is the procedure of choice for decontamination of solid and liquid wastes. Many viruses are relatively heat-labile—HIV is inactivated at... 

The waste is assumed to be agent-contaminated and is decontaminated in accordance with the RCRA permit or regulations adequate decontamination (<1.0 VSL) is verified via monitoring at the SDU or autoclave, whereupon it is reclassified as clean and shipped offsite or... 

Following approach 1, if <1.0 VSL, the waste is classified as clean and shipped offsite, and if >1.0 VSL, approach 2 or approach 3 is followed (PMACWA. 2006). Adequate decontamination, defined as <1.0 VSL, may need to be accomplished in the SDU or the autoclave and verified via monitoring at the SDU or the autoclave. As previously indicated, Table 4-6 shows the total estimated secondary wastes, while Tables 4-7 and 4-8 show projected generated quantities of contaminated secondary wastes according to their level of contamination (before any onsite treatment) for the operational and closure stages of PCAPP, respectively. 

BPT. 2007. Final Report of Integrated Product Team (IPT) 10 on Secondary and Closure Waste Treatment, Including Supplemental Decontamination Units (SDUs) and Autoclaves, Rev. B, February 22. Aberdeen Proving Ground, Md. Program Manager for Assembled Chemical Weapons Alternatives. 

A method for decontamination of infectious or regulated laboratory waste is available (e.g., autoclave, chemical disinfection, incinerator, or other approved decontamination system). 

All wastes from the animal room are to be appropriately decontaminated, preferably by autoclaving, before disposal. Infected animal carcasses are to be incinerated after being transported from the animal room in leakproof, covered containers. 

An autoclave which can be used for decontaminating infectious laboratory waste is available in the building with the animal facility. 

An autoclavefordecontaminating wastes is available,preferably within the animal facility. Materials are transferred to the autoclave in a covered leak-proofcontainerwhose outer surface has been decontaminated. 

Two new autoclaves one for the sterilization of consumables prior to processing, the other for decontamination of waste materials. 

Safety gloves, coats, gowns, or uniforms should be worn while working with potentially infectious materials. Never wear these outside the working area, and these should be changed at least once per week. If they are obviously contaminated, they should be decontaminated (by autoclaving) prior to laundry, or disposed off as hazardous waste. 

Before disposal, laboratory waste should always be decontaminated by autoclaving and all waste should be identified by unambiguous labeling whether or not the decontamination had been carried out. Remains of biological material (e.g., blood or tissue samples) should be regarded as hazardous material. Chemicals should be treated as hazardous if they are ignitable, corrosive, reactive, or toxic. 

Decontamination of wastes by autoclaving can be somewhat tricky, since the efficacy of this technique relies on the penetration of steam into every portion of the load (242), and the contact time (the time that the steam contacts all portions of the load) and the autoclave set time (the time set on the autoclave timer) are rarely equal. In fact, for large loads, it has been demonstrated that complete steam contact times can lag autoclave set times by a factor of four or more (254), resulting in incomplete sterility or decontamination. In all cases, the manufacturer s recommendations for the operation of the steam autoclave should be followed. 

Packaging materials. The composition and preparation of the material used to package the material to be decontaminated can interfere with the process. Waste sealed in plastic bags, for example, is almost impossible to decontaminate. In fact, even the so-called autoclavable plastic bags do not always allow for penetration of the steam to the interior. 

Chamber loading. The volume of waste in the autoclave chamber has a major effect on the time required for decontamination. Also, how the bags or other contents are placed in the chamber affects the penetration of the steam. In order for the autoclave to operate properly, the steam must be able to circulate freely to reach the bottom of the chamber. 

Biowastes and used materials must be promptly removed and prepared for decontamination (see Chapter 5). Pathogen-containing liquid wastes and recombinant DNA materials shall be autoclaved before disposal. CAUTION Autoclaving of radioactive materials may be prohibited by local policy. Contaminated media should be treated with 1 percent chlorine bleach and 2 percent iodophor solution if this disinfectant will not react with the materials to be decontaminated. 

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