LAB2.4 - Generic risk assessment for the lab use of hypodermic needles
The use and disposal of hypodermic needles is a high risk activity
These notes are not exhaustive.
|Risk control measures;|
Is it necessary to use hypodermic needles?
In laboratory situations the use of hypodermic needles should be minimised. They should not be used (when attached to a syringe) as substitutes for pipettes. Metal needles may be substituted by cannulae or fine plastic tubing. Gadgets for removing septum caps from reagent bottles are available, thus allowing conventional pipettes or pipettors with plastic tips to be used.
The deliberate use of hypodermic needles to
introduce material into, or take blood from, humans is only permitted
by qualified medical staff or, with animals, Home Office personal licence
Hazards of hypodermic needles.
"Needlestick" injuries. Hypodermic needles are designed to penetrate body tissues, to facilitate the introduction of fluids or to remove blood. Thus a penetrating injury with a needle is very likely to introduce material contained inside the needle (and syringe if attached) into the body. Material on the outside of the needle may also be introduced into the wound. As a consequence, work using needles containing pathogenic micro-organisms or other hazardous materials will require a Special Assessment.
The major biological hazard from needles contaminated with human material are infections of hepatitis B and C and Human Immunodeficiency (HIV) viruses. The hepatitis viruses are more infectious than HIV and can also kill. For needles contaminated with soil (earth) or dirt on floors there could also be a risk from tetanus.
For needles used in transferring chemicals the hazard depends on the properties of the individual chemical.
Following a needlestick injury where the use of the needle (and hence the needle contents) is not known there may be severe psychological trauma due to the fear of acquiring an infection or from a fear of poisoning. Hence the user MUST ensure that all needles, regardless of the use to which they are to be put, are obtained, used and disposed of with great care (see section "Risk Control Measures").
There will also be a degree of physical injury caused by penetration and/or scratching.
Bearing in mind that very little work is done in Department laboratories involving human material, the actual risk of infection from human material is low and should be kept in perspective. Having said that, actual risks of infection depend on;
With hazardous chemicals in a needle the risk depends on the properties of the chemical. Only tiny amounts are likely be transferred in a needlestick injury
Using the needle. It is the unsheathed needle that offers the hazard and it must be made safe. There are 3 obvious control options that might prevent injury to the user and any other person concerned with work in the laboratory or support services. After using the needle;
Resheathing of the hypodermic needle can be accomplished
safely, depending on the hazard of the material in the needle.
Having removed the unused needle from the sheath (directly onto a
syringe if using one), the simplest means is to place the sheath on
a level surface with the opening towards the operator. After use the
needle is guided into the sheath and lifted so the sheath falls over
it. Alternatively, commercial devices, such as "Needle Guard"
and "Safe T Cap" can be purchased. These hold the sheath
in such a way that the needle can be inserted into the sheath in a
one-handed operation. If required, the sheathed needle can then be
detached safely from the syringe and placed promptly in the Sharpsbin.
|Stores code 3822346
Stores code 3822352
Stores code 3822369
They can be autoclaved at any time, both during a period of use
and after, to inactivate any biological contamination. When full
(as indicated by the fill-line printed on the Sharpsbin and not when
items protrude through the opening) the sealing closures must be made
secure and they should be taken to the autoclave room, unless
an overt chemical or radiochemical hazard is known to be present in
which case they should not be autoclaved. After autoclaving the tops
should be additionally secured with packaging tape. The Sharpsbins
will be collected, on demand, by the Contaminated and Hazardous Waste
Service. Full Sharpsbins are sent for incineration as clinical waste.
Reporting procedure in the event of an incident (actual needlestick injury or a needle "find"). The University Safety Officer (Peter Adams, WH 3.19, ext 6834, e-mail P.C.E.Adams@bath.ac.uk) should be contacted immediately a needlestick injury occurs. (Leave a message outside normal working hours.) An Incident Report Form (copies of which are available in all first aid boxes) must be completed as soon as possible after the incident or needle find and sent to the Safety Office. The University Medical Officer will be made aware of an injury by the Safety Officer and appropriate medical advice given and other relevant actions taken. Within 48 hours of a needlestick injury a protective injection can be given against Hepatitis B.
This assessment was drafted by Peter Jewell and originally adopted
by the Safety Team in May 1998 and reviewed in April 2000, May 2001,
May 2003 and May 2005.
Signed by Peter Jewell
Departmental Safety Co-ordinator
Signed by Professor Jonathan Slack,
Head of Department
1st June 2005