Scope and Applicability
The collection of autoclaved soil, plants, and plant materials must be conducted in a manner that follows the correct waste stream and does not create ergonomic risks for facilities personnel. This guidance applies to the collection, treatment and disposal of all soil and plant material as defined below. This shall apply to all students, staff and faculty responsible for handling and disposing of soil, plants, and plant materials.
For those who autoclave and dispose of their lab’s bagged biowaste, this document serves to clarify the expectations for collection, treatment, and final disposal. Bagged biowaste falls into one of two broad categories: 1) medical waste as defined and regulated by the TN Department of Environment & Conservation (TDEC; *see below for definition), and 2) that not fitting the description/definition of medical waste, other for the purpose of this guidance.
Medical Waste – Medical waste generally includes cultures/stocks of wild type or recombinant infectious agents (i.e., to humans), human-derived materials (blood, body fluids, tissues, cell lines, etc.), nonhuman primate cell cultures, and materials contaminated with these. Labs operating at Biosafety level-2 (BSL-2) will likely generate this type of waste.
- Collection: Solid wastes are to be segregated into labeled biohazard waste cans lined with an autoclavable waste bag (e.g., polypropylene bag). The bag must be orange/red in color and/or emblazoned with a biohazard symbol. (Note: this excludes sharps, gross pathological/tissue waste, and bulk liquids; see http://biosafety.utk.edu/waste/ for information on these types of waste).
- Treatment: Bags must be autoclaved in accordance with posted time/temperature parameters which are verified quarterly (parameters/instructions posted on/near approved autoclaves).
- Disposal: cooled autoclaved bags are to be segregated to the large white BruteTM bins labeled ‘Autoclave-treated waste’. These are located in each building with labs which may generate treated medical wastes, typically in/near autoclave rooms. They are used to keep treated medical waste separate from other routine solid wastes in accordance with TDEC regulations. Autoclaved red/orange/biohazard-labeled bags cannot be comingled with routine solid waste and are NOT to be placed in your standard lab waste cans or building dumpsters.
Materials collected in each interior bag of the white BruteTM containers must not exceed 50 lbs. and directions on posted signs must be followed.
Other – biological waste not meeting the definition of medical waste would include cultures/stocks of routine or recombinant noninfectious (i.e., to humans)/Risk Group 1 microbes (E. coli K-12, Saccharomyces cerevisiae, low risk soil/plant materials/waterborne microbes, etc.)
- Collection: Solid wastes are to be segregated into a waste can identified for biological waste (a biohazard decal on the can is acceptable). The can must be lined with an autoclavable bag:
- May be orange/red and/or labeled as indicated above; OR
- May be a clear/white, unlabeled (not bearing a biohazard symbol) bag.
- Treatment: As indicated for medical wastes above; autoclave must be validated quarterly/follow posted parameters.
- Disposal: cooled autoclaved bags are to be disposed as follows:
- Orange/red and/or labeled bags must be placed in white bins as indicated in 1-c above.
- If bag is clear/white and unlabeled it may be disposed as routine solid waste or directly to building dumpster. For bagged biowaste that does not meet the TDEC regulatory definition of medical waste, this methods offers the advantages of cost savings both in bag type and in disposal costs.
Collection, treatment, and disposal of plants, plant materials and soils
Soil and plant wastes do not qualify as ‘regulated medical waste’ per state code, so these are not subject to special segregation into the white bins. However, to meet this exemption these wastes cannot be collected in an autoclave bag that is red (or orange) or bears the biohazard symbol (i.e., it must be a plain white/clear/tan autoclave bag). The bags can then be placed directly into the dumpster once autoclaved/cooled. Dry cycles can be incorporated into soil sterilization to possibly help reduce the weight of autoclaved soil. While this guidance pertains to all materials in the “Other” category above, it is especially important to be followed for autoclaved soils and plant materials as they contribute 11x more to the cost of disposal than other materials in the waste stream.