These guidelines are for the disposal or decontamination of contaminated pipettes, including viral contamination, by appropriate disinfectant and autoclaving.
A suitable discard container, with a minimum height of 280 mm, constructed of autoclavable plastic or stainless steel should be filled with the recommended disinfectant, presently two per cent phenolic. The level should be such that pipettes can be lifted out without getting disinfectant on the fingers. Each school should specify the appropriate disinfectant for their own work.
Containers for reusable pipettes should contain a pad of a disposable material such as foam plastic to protect the tips. The container should be wide enough at the base to be stable.
Place on the laboratory bench, or floor in some cases, for use.
Where viral contamination is the main concern, one per cent sodium hypochlorite should be used, with one ml/litre of three per cent potassium permanganate added as an indicator. Use only while the fluid is pink. If the disinfectant has decolourised, the container should be decontaminated and reused.
Discard the pipette directly into the fluid. Avoid touching the top of the discard container and expelling droplets onto the sides of the container. The pipettes should be covered as in Container preparation.
Rubber teats and pumpettes should be removed after the tip of the pipette has been placed under the surface of the disinfectant.
Swabs and spatulas must not be discarded into the same containers as pipettes.
When ready for decontamination, transport the container to the autoclave room. Fold 10 cm of adhesive autoclave tape in half, with the adhesive sides together, and place on top of the contents of the container. This procedure is to avoid the build-up of used, heat-treated autoclave tape on the sides of the container.
Place in the autoclave.
After completion of autoclaving the fluid can be discarded down the sink, and the pipettes rinsed ready for washing or disposal. Protective gloves are to be worn.
Graduated and reusable pipettes should be rinsed and washed routinely.
Disposable and pasteur pipettes should then be treated as broken glass (see Procedure for non-contaminated disposable glassware and broken glass).