Waste Management Plan for Autoclaved Waste Generated at Clayton Campus

1. Background

Physiology, Pharmacology, Anatomy, Microbiology, Biochemistry, Biological Sciences and the Centre for Molecular Biology & Medicine are teaching and research departments located at the Monash Clayton Campus. All of these departments use micro-organisms and have developed safe and secure laboratory practices for dealing with them.

1.1 Regulations and Guidelines Used

All of the above departments comply with numerous relevant guidelines and regulations, including:

• Genetic Manipulation Advisory Committee (GMAC) - Guidelines for Small Scale Genetic Manipulation Work (1995)
• Australian Quarantine Inspection Service (AQIS) - Registration of Scientific Institutions for the Handling of Imported Biological Material and Requirements for Importation of Biologicals for Diagnostic Analytical and Research Purposes (1992)
• National Health and Medical Research Council (NH&MRC) - National Guidelines for the management of Clinical and Related Wastes (1988)
• Australian Standard AS/NZS 2242-3 1995 Safety in Laboratories. Part 3 Microbiology

The Monash University Biosafety Committee has produced a Biosafety Manual which sets out guidelines to be followed when biohazardous organisms are being used. This also includes the appropriate methods of biohazardous waste disposal.

1.2 Waste Disposal

Currently, all departments are in full compliance with the waste disposal requirements for chemicals, radioisotopes, general office waste and liquid autoclave waste. These wastes are segregated into the appropriate categories and are disposed of as:

1. liquid trade waste in compliance with our Agreements with Yarra Valley Water.
2. prescribed industrial waste using EPA prescribed waste transport certificates, EPA licensed transporters and EPA licensed disposal or treatment sites
3. general office waste which is recycled when possible or disposed of as general rubbish to sanitary landfill.

This plan addresses the disposal of solid autoclave waste from laboratories which are graded as Physical Containment Level 1 or 2 (PC1 or PC2).

All waste arising from work with micro-organisms is regarded as potentially hazardous and therefore the procedures used for waste disposal reflect this concern.

1.3 Infectious Agents at Monash University

The types of infectious agents used by departments, as defined by AS/NZS 2243.3 1995 are:

• "Risk Group 1 Organisms - low individual and community risk micro-organisms that are unlikely to cause human, plant or animal disease", and
• "Risk Group 2 Organisms - a moderate individual risk and limited community risk pathogen that can cause human, plant and animal disease but is unlikely to be a serious hazard to laboratory workers, the community, livestock, or the environment. Laboratory exposures may cause infection but effective treatment and preventative measures are available and the risk of spread is limited".

Note: Microbiology currently holds a single Risk Group 3 organism: St Louis Encephalitis virus. It is a mosquito-borne virus and the mosquito host does not exist in Australia. This virus is being held for use as a reference for other laboratories. No research is being carried out using this organism and therefore no waste is generated.

1.4 Records of Organisms Used

Lists of all organisms possessed and used by the various departments are held by the departmental Biosafety Officer and the University Biosafety Committee. The acquisition of any new organism by departments must be reported to the Biosafety Officer so that documentation can be kept up to date. The destruction of any organism must also be reported and documented.

2. Waste Management Plan

2.1 Scope/Area

This plan applies to the waste generated from PC2 areas such as; research laboratories, teaching laboratories and animal houses in the departments of Microbiology, Biochemistry and Molecular Biology, Biological Sciences, Physiology, Pharmacology, Anatomy and the Centre for Molecular Biology and Medicine. It encompasses the pre-treatment methods and final disposal route for solid microbiological waste as described below. Human blood and body fluids are subject to additional formal University Guidelines and Policy Directives.

2.2 Potentially Contaminated Waste Description

• Research/Teaching Laboratories
  • Sharps
  • Disposable plastic items e.g. petri dishes, pipette tips and tubes
  • Glassware - broken glass and Pasteur pipettes
  • Soil and plant material
• Animal Houses
  • Sharps
  • Carcasses
• Bedding materials

2.3 Waste Treatment

Each category of waste is segregated and is then treated separately.

Sharps : e.g. syringes, needles, blades:

• Are placed into mediwaste containers
• Full mediwaste containers are then held in a central, secure locked waste store
• The mediwaste containers are regularly collected by an EPA licensed waste transporter, under Monash supervision, for high temperature incineration.

Disposables - Plasticware

• Segregated in laboratories into biohazard bags and placed into autoclavable containers.
• The only route of disposal is via each department's designated autoclave facility.
• The containers are placed in the autoclave for sterilisation, the lids are removed and the bags opened.
• After the autoclave cycle, the biohazard bag is labelled with tape printed "Sterile".
• The waste is then double-bagged into a black opaque bag and sealed with tape printed "Sterile".
• The outer bag is numbered and labelled by the department.
• A record of the bag's contents and treatment cycle is recorded.

Glassware : e.g. flasks and culture bottles

• Segregated into autoclavable containers and autoclaved with the lids removed.
• After the autoclave cycle, sterile solutions are poured down the sink.
• Glassware is washed.
• Glassware is re-autoclaved to ensure sterility for re-use.

Glass Pipettes

• Placed in receptacles containing fresh 5% hypochlorite solution; the solution is changed daily.
• The pipettes and hypochlorite solutions are neutralised by the addition of thiosulphate (to prevent chlorine gas production in the autoclave).
• The receptacles, pipettes and neutralised solutions are then autoclaved.
• On completion of the autoclave cycle the neutralised solution is poured down the sink.
• Pipettes are washed.
• Pipettes are baked in a hot air oven or re-autoclaved to achieve sterility and returned to the laboratories in metal canisters.

Broken Glass and Pasteur Pipettes

• Are placed into autoclavable containers.
• Autoclaved
• Placed in glass recycling bins.

Soil and Plant Material

• These are autoclaved according to GMAC requirements.

Animal Carcasses: (e.g. mice, rabbits) originating from PC2 facilities.

• All carcasses are autoclaved
• Bagged and frozen
• Taken to Department of Physiology and burnt in the Animal House incinerator (previously EPA licensed for this purpose now exempt; EA2849/3 Discharge Point No. 50).

Animal Bedding : originating from PC2 facilities.

• Bedding from a maximum of two cages is placed in an autoclave bin.
• The bedding is moistened to promote heat transfer.
• The boxed bedding is autoclaved.
• The bedding is then placed into a biohazard bag which is labelled with tape printed "Sterile".
• The bedding is double-bagged into a black opaque bag and sealed with tape printed "Sterile".
• The outer bag is numbered and labelled by the department.
• The contents of each bag and the treatment cycles are recorded.

2.4 Waste Minimisation

The opportunity for further waste minimisation is difficult due to over-lapping controls from the regulatory authorities.

Single Use Items: Currently, the following single-use items are being used at Monash:

• Pasteur pipettes
• Plastic petri dishes
• Some glassware

Alternatives to disposable plasticware, such as plastic pipettes, tips and tubing are under constant review.

Recycling: Recycling is carried out wherever possible in accordance with waste minimisation principles. Recycling and use of glass petri dishes is currently not feasible due to the associated high costs.

3. Autoclave Operation

3.1 Monitoring of Autoclave Operation

• Temperature Monitoring: Only autoclaves fitted with a recording system having automatic printout of temperature and time cycle for every load will be used. The automatic printout will be set so that a reading of the temperature is recorded at least every three minutes. A minimum of fifteen readings per load cycle is required. Where the cycle is shorter than 45 minutes, readings must be taken at more frequent intervals (ie less than 3 minutes).
• Controls & Failsafes: All autoclaves used for sterilisation of infectious waste have automatic controls and failsafe operation
• Annual Inspection: Autoclaves used for sterilisation of infectious wastes undergo an annual inspection for safety. This involves external examination, chamber inspection and use of a thermocouple. Results of the annual inspections are kept by the resources manager in each department. (NB: to date these records indicate no variation in autoclave operation).
• Thermalog Strips:
  1. Thermalog strips which are both temperature and time dependent will be placed in each autoclave load. Where the loads are similar with regard to the heat resistance, density, volume and nature of material in the load, the number of thermalog strips used may be reduced to one thermalog strip per batch type per week. At least one thermalog strip per week must be used to monitor batches of similar constitution.
  2. The thermalog strip will be placed into a heat resistant tube, which is then placed either into the centre of a load or where applicable into the most heat resistant part of the load.
  3. After the autoclave cycle the thermalog strip will be recovered and the amount of development checked and recorded.
  4. The standard cycle run is between 20 and 70 minutes at 121 °C at 103.4 KPa. From experience it has been found that these cycles allow for sufficient heat penetration to all areas of the load so that complete sterilisation can occur.

Bacterial checks:

1. Once a month, all involved departments will use a culture of spore-forming bacteria, perform a viable count to determine cell numbers and place the culture in the centre of the load. After the autoclave cycle samples will be removed from the culture and plated out. This will test for the presence of any viable cells.
2. The viable cell count will determine whether the autoclave operation results in a 99.9999% annihilation of micro-organisms in the waste.
3. After six months, a review of the viable count results for each department will be carried out. If the results indicate complete sterilisation, then the viable count testing will be reduced to a quarterly assay.

3.2 Log Books

Log Books for each autoclave control area will be maintained to record:

• Date
• Bag number
• Thermalog result and Thermocouple test results
• Plate count tests
• Bag labelling check

The Log Book entry will be signed by the autoclave operator for each load and daily by the supervisor for that area.

3.3 Operator Training

• Autoclave Operator: The autoclave operator will have received individual instruction in the operation of the autoclave.
• Supervisor: The supervisor will have appropriate qualifications and/or attended the Monash University Biosafety course.

3.4 Bag Labelling

• Label will include Department name, Autoclave Area and Bag Number.
• Appropriately bagged waste will be placed in bins. Each bin will be checked by a supervisor to ensure only labelled bags are placed in the bins.
• Bins will be kept in secure locations.
• Bins will be taken to the collection point just prior to removal by the waste contractor. All waste will be disposed of to sanitary landfill.