Ionising Radiation Risk Assessment (IRR99, Reg 7)
ROUTINE LABORATORY WORK WITH SMALL QUANTITIES OF RADIONUCLIDES
Effective Date:
Review by:
Author:
Signature
Version
Date
Date
Reason for Change
Introduction:
Under the Ionising Radiation Regulations 1999 (IRR99) the University of Sussex is required to monitor the use
of radioactivity by employees and to minimise any dose received as far as it is reasonably practicable.
The purpose of this risk assessment is to restrict exposure to Users of ionising radiations and those who by
association may be exposed, e.g. co-workers, students, maintenance and cleaning staff.
It is a requirement to complete a prior radiation risk assessment before starting work with any radioactive
materials. This risk assessment must be reviewed following any significant change in circumstances.
This risk assessment must be completed by the project supervisor and returned to the relevant RPS for
processing. If required a separate form will be completed by the RPA. Once the assessment is completed and
signed by all relevant parties the document will be held on file by the RPS, RPO and returned to the
staff/students involved in the work.
If the activity or number of procedures per month is higher than listed in this table then a bespoke
calculation will be required by the RPA.
Max activity per procedure (MBq)
Max procedures / month
H-3
C-14
P-32
S-35, P-33
500
100
20
100
Written by: Dr Teresa Knapp and Mr Mark Aplin
Ionising Radiation Risk Assessment v1.0
October 2014
No limit
No limit
20
No limit
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Ionising Radiation Risk Assessment (IRR99, Reg 7)
ROUTINE LABORATORY WORK WITH SMALL QUANTITIES OF RADIONUCLIDES
Procedure(s) covered by this
assessment
Ref: R
Name of person who will take overall
responsibility for compliance (RPS)
Name of person who will take overall
responsibility for supervision of work
(Project Supervisor)
Location where the work involving
ionising radiations will take place
Please give building name and room
number(s)
Radionuclide
Typical activity (MBq)
ordered
per procedure
Typical number of
Duration of work (days / weeks
procedures per month
/ months / years)
H-3
C-14
P-32
S-35
Please tick the relevant control measures that will be used
Non-radioactive alternatives
☐
Lab coat
☐
Less radioactive alternatives
☐
Gloves
☐
Lead Shielding (γ emitters)
☐
Safety glasses
☐
Perspex shielding (β emitters)
☐
Security measures
☐
To minimise contamination
Fume cabinet
☐
Segregation from other work
☐
Remote handling tools
☐
Work trays
☐
Procedures / systems of work / local rules
☐
Benchcote
☐
Please provide any other relevant experimental details
Yes
No
Will aerosols be produced?
☐
☐
Will volatile substances be used or produced?
☐
☐
Will experimental animals be involved?
☐
☐
Written by: Dr Teresa Knapp and Mr Mark Aplin
Ionising Radiation Risk Assessment v1.0
October 2014
Page 1 of 4
Ionising Radiation Risk Assessment (IRR99, Reg 7)
ROUTINE LABORATORY WORK WITH SMALL QUANTITIES OF RADIONUCLIDES
Please provide any other relevant experimental details
Main disposal
routes (% of
original activity)
☐
☐
☐
☐
Solid
Aqueous Liquid
Organic Liquid
Other - please describe:
Who might be at risk
☐ Staff ☐ Students ☐ Visitors ☐ Public
☐ Young people (<18yrs) ☐ New and expectant mothers
☐ Other – please describe:
Project Supervisor Name:
Project Supervisor Signature:
Date:
RPS Name:
RPS Signature:
Date:
RPA Name: Not required
RPA Signature:
Written by: Dr Teresa Knapp and Mr Mark Aplin
Ionising Radiation Risk Assessment v1.0
October 2014
Date:
Page 1 of 4
Ionising Radiation Risk Assessment (IRR99, Reg 7)
ROUTINE LABORATORY WORK WITH SMALL QUANTITIES OF RADIONUCLIDES
User Signature
Radiation License No.
Date
Notes
Radiation dose rates and external radiation risk to individuals
Tritium, carbon-14, phosphorus-33, sulphur-35
These are all low energy beta-emitters readily shielded by normal laboratory containers, etc. These are not expected
to give rise to a significant external radiation hazard during normal use.
Phosphorus-32
Beta dose rates during normal procedures are usually negligible due to the Perspex shielding provided. The highest
dose rates measured are above the open stock vial. For a typical stock vial, it is estimated that the dose rate at 10 cm
above the open vial (i.e. where the fingers might be) is 1500μSv h -1. Elsewhere, dose rates are all very low. A typical
procedure will require no more than a few seconds exposure of the hands above the stock vial. Assuming 10 procedures
a month gives an annual dose to the skin on the fingertips of less than 0.5mSv, equivalent to 0.1% of the annual dose
limit of 500mSv.
To ensure that doses remain low, the use of shielding around stock vials, pipettes, and on benches is very important, as
is avoiding any direct handling of unshielded (or poorly shielded) activity. Without such precautions, it is estimated that
the skin dose could be very much higher.
Contamination levels and internal radiation risk to individuals
In all cases, the work is small-scale in nature; typically involving limited quantities (a few ml) of radioactive solutions.
There is the potential for contamination to arise, for example through small spills or the handling of contaminated
articles. Any contamination would be expected to be low level (major spills are considered later) and highly localised
(e.g. a small “spot” on a workbench). Air contamination is not expected to occur from most procedures. Ordinary
laboratory procedures are considered sufficient to prevent the spread of contamination and intakes of radioactive
materials.
In summary, internal radiation doses from normal operations are expected to be negligible provided that:
 Good laboratory practice is observed
 Contamination routinely arising from the work is low-level and localised
 Airborne contamination is not expected.
Written by: Dr Teresa Knapp and Mr Mark Aplin
Ionising Radiation Risk Assessment v1.0
October 2014
Page 1 of 4