Glass pipettes: a source of common laboratory injuries - hazard alert

March 1999

Background

Each year, accidents involving the use of glass pipettes in undergraduate and research laboratories at Monash University cause lacerations to the hands of operators. A small percentage of these incidents result in very serious injuries.

The cause of injuries

As outlined in Australian Standard 2243.1 (1997): Safety in Laboratories, Part 1: General, mouth pipetting is prohibited. The use of pipette aids/fillers/pumps is an acknowledged safety practice to avoid mouth contact with chemicals and biological materials. However, when a glass pipette is being inserted into a pipette filler, the pipette may break resulting in laceration to the hands of the operator. Similarly, placing the rubber bulb onto a glass Pasteur pipette ready for use, can result in injuries to the hands if slippage occurs and the Pasteur pipette fractures.

Options available to decrease the risk of injuries occurring with the use of glass pipettes

The options that are available to prevent the types of injuries found to occur with the use of glass pipettes are described below. Laboratory supervisors in each department should adopt the option(s) most suitable for the techniques used in each particular undergraduate, postgraduate or research laboratory. The strategies implemented must either eliminate or reduce the risks associated with the use of glass pipettes. Training in the use of pipette fillers cannot be seen as a sole control measure as it is not possible to eliminate the likelihood of human error.

1. Alternatives to pipettes

Pipettors that use a plastic disposable tip to dispense volumes from ~5 ml to 5 ml eliminate the risk of the injuries described. Brand names of commonly used pipettors are Brand, Eppendorf, Finnpipette, Gilson, Oxford and Transferpette.
Repetitive dispensing from a single bottle of a solution can be carried out using a dispenser such as Brand Dispensette, Fortuna Optifix, Jencons Zipette, Organon Teknika and Trubor.

2. When compatible with materials in use, plastic pipettes can be used in place of glass pipettes

Polycarbonate pipettes can be used to replace glass bulb and graduated pipettes.
Disposable polyethylene Pasteur pipettes can be used in place of glass Pasteur pipettes. These pipettes are moulded as one piece with the bulb incorporated into the body of the pipette. It is, therefore, not necessary to purchase separate bulbs.

3. Use of safer pipette aids

Safety pipette filler	A rubber pumpette, which inserts into the end of the pipette, and has no valves, is available from Ozasia. At La Trobe University, this safety pipette filler has no recorded pipette breakages. The Department of Chemistry has adopted this pipette filler for use in first year undergraduate laboratories. This pipette aid is not suitable for pipettes that have a cotton wool plug.
Automatic pipette pumps can be used to replace pipette aids	A pipetting station utilising an electrically- or battery-operated pump can be set up in each research laboratory or at several points in an undergraduate practical laboratory to service several staff or students. Common brand names of pumps used are Brand, Biohit, Rainin.

4. Glass pipettes can be encased in 'Shrink Wrap' plastic

Transparent 'shrink wrap' plastic tubing is available from Radio Parts (West Melbourne) in sizes >1.2 mm. After placing a length of the tubing around the pipette, heat provided by a heat gun, hair dryer or oven is used to shrink the plastic to tightly coat the glass. The shrink-wrapping contains the glass if the pipette is broken, thus preventing injury to the hand of the operator.

5. Training of new staff and students

It is essential that the use of all types of pipette aids be accompanied by training of staff and students in the correct technique to insert the pipette into the pipette aid
Laboratory supervisors, practical class coordinators and demonstrators must ensure training is provided to individuals or small groups of students. The techniques used by students should be observed during practical classes and corrected where necessary
The incorporation of diagrams into practical class notes and laboratory safety manuals will assist this training
Questions related to the use of pipette aids can also be included in a safety quiz or multiple choice questions related to practical sessions

Further information

Please contact OH&S on:

Telephone: 990 51016
Email: ohsehelpline@monash.edu