POLICY ON RADIOACTIVE MATERIALS
HEALTH & SAFETY UNIT
SUMMER
TERM
2014
CONTENTS
1 AIM OF THE POLICY .......................................................................... 3
2 INTRODUCTION ............................................................................... 3
3 MANAGEMENT................................................................................. 4
4 ORGANISATIONAL STRUCTURE FOR RADIATION PROTECTION ......................... 4
4.1 Radiation Protection Adviser (RPA) .................................................... 5
4.2 Radiation Protection Officer (RPO)..................................................... 5
4.3 Radiation Protection Supervisor (RPS) ................................................. 5
4.4 Radiological Protection Sub-Committee ............................................... 5
5 WORK PRACTICES AND JUSTIFICATION ................................................... 5
6 RESOURCES ................................................................................... 6
7 QUALIFIED AND EXPERIENCED STAFF ..................................................... 6
a) Staff Training ............................................................................... 6
b) Training Records ............................................................................ 7
8 USE AND STORAGE OF UNSEALED RADIOACTIVE MATERIAL ............................ 7
a) Practices ..................................................................................... 7
b) Appropriate Method ........................................................................ 7
c) Ordering and Storage of Radioactive Material ......................................... 7
9 GENERATION AND DISPOSAL OF RADIOACTIVE WASTE .................................. 7
a) Segregation of Waste ...................................................................... 7
b) Estimation of liquid/solid waste ......................................................... 8
10 ACCUMULATION OF RADIOACTIVE WASTE .............................................. 8
11 DISPOSAL OF RADIOACTIVE WASTE ...................................................... 8
a) Liquid Waste................................................................................. 8
b) Solid Waste .................................................................................. 8
12 COMPLIANCE WITH THE RADIOACTIVE SUBSTANCES ACT............................. 9
a) Open Source Registration ................................................................. 9
b) Waste Disposal Authorisation ............................................................. 9
c) Audit .......................................................................................... 9
d) Documents ................................................................................... 9
13 GENERAL .................................................................................... 9
a) Radiological Protection Sub-Committee ................................................ 9
b) Reports ...................................................................................... 10
14 APPENDIX I RSA3 ASSESSMENT ......................................................... 11
SUMMARY ....................................................................................... 15
2
1 AIM OF THE POLICY
To demonstrate the employment of “Best Practicable Means” (BPM) for the
usage of radioactive materials and disposal of radioactive waste in
accordance with the provisions of the Ionising Radiations Regulations 1999
(IRR1999), The Environmental Permitting (England and Wales) Regulations
2010 and associated guidance.
2 INTRODUCTION
This document sets out to demonstrate that Manchester Metropolitan
University is committed to complying with the standard conditions issued with
its authorisation to accumulate and dispose of radioactive waste, and in
particular applying “best practicable means” for the work that is carried out at
the University. To this end, the document refers to:

An assessment of the radiological impact on members of the public
and the environment of the release of radioactive waste in liquid form.
Whilst details of that assessment is contained in Appendix I, it is noted
that the total committed effective dose to a member of the public or
sewage worker under the worst possible scenario is unlikely to be
greater that 3 microsieverts. Interim guidance from the Environment
Agency states that “the Agency expects the amount of work
undertaken to demonstrate that BPM is applied to be proportionate to
the assessed environment risk. In addition, the amount of time, money
and trouble expending BPM measures should also be proportionate to
the environment risk being mitigated”. This statement, together with the
assessment of total committed effective dose, has been taken into
account for the work undertaken.

The role of management and the procedures employed to adopt the
delegation of responsibility and organisation of formal meetings etc.

The work practices on site, the resources allocated for them and their
justification.

The role of staff, the use of radioactive material and the procedure of
waste disposal.
Since the assessment assumes that the waste disposed of is the maximum
limit set in the authorisation, any changes in the authorisation will necessitate
a review of the assessment.
3
3 MANAGEMENT
The University Health and Safety Policy identifies the senior individuals who
are responsible for delivering the policy commitments. Details of their duties
and responsibilities are set out in the University’s Health and Safety Policy
Manual.
4 ORGANISATIONAL STRUCTURE FOR RADIATION
PROTECTION
ORGANISATIONAL CHART FOR RADIATION PROTECTION
Vice Chancellor
Deputy Vice
Chancellor
Deans/Pro Vice
Chancellors
University
Secretary
Human
Resources
Director
(Appointed
Safety Director)
Heads of
School/
Departments
University
Health & Safety
Adviser
Departmental
Radiation
Protection
Supervisor
University
Radiation
Protection
Officer
Financial
Director
Radiation
Protection
Adviser
(External
Appointment)
For the purpose of Radiation Protection, the University will appoint the
following to ensure compliance with all relevant legislation in order to protect
the health and safety of its students, staff and visitors.
4
4.1 Radiation Protection Adviser (RPA)
The University has appointed Peak RPA as it’s Radiation Protection Adviser,
as outlined in Schedule 5 of IRR99 and the Approved Code of Practice.
Advice from the RPA will be sought as necessary for implementation of IRR99
and RAS93.
4.2 Radiation Protection Officer (RPO)
The University has appointed a Radiation Protection Officer to provide
guidance and support to ensure that the requirements of the Ionising
Radiation Regulations and The Radioactive Substances Act are met. The
RPO will provide support and co-ordinate on ionising radiation issues with
both the RPA and the RPS’s.
4.3 Radiation Protection Supervisor (RPS)
The University will appoint Radiation Protection Supervisors from all
Departments that use ionising radiation to provide an adequate level of dayto-day supervision of each Department’s work with radiation, as required by
the IRR99. Where the work with ionising radiation is such that RPSs are not
required (for example where there are no Controlled Areas), appropriate staff
will be delegated duties to oversee compliance with RSA93 and any other
relevant legislation.
4.4 Radiological Protection Sub-Committee
The University’s Health and Safety Committee will appoint a Chairperson to
lead the Radiological Protection Sub-Committee. The Radiological SubCommittee will report to, and will be responsible for advising, the University’s
Health and Safety Committee on measures to permit the legal and safe use of
sources of radiation, and the protection of persons liable to be exposed to
radiation hazards. The Sub-Committee will provide advice to the University on
the state of compliance with the Regulations, and will identify specific
problems relevant to the use of ionising radiations and other issues relating to
the radiological safety of the University’s activities. The RPA will be a member
of the Sub-Committee.
5 WORK PRACTICES AND JUSTIFICATION
Unsealed radionuclides are used to label proteins, RNA and DNA to develop
assays to increase the sensitivity of detection of the above. Radioactive
sources are in liquid form and uptake in the probe for protein, RNA and DNA
is normally very little of the original activity. The unattached activity is treated
as aqueous waste.
5
This is vital work that uses established techniques in the field. Many
Universities and research facilities employ these methods. In these
techniques enough radioactivity has to be incorporated in the probe to be able
to get statistically viable results. The least amount of radioactivity that will
yield meaningful results is normally employed.
It is normal policy at the University to ask researchers to consider nonradioisotopic methods when carrying out a prior risk assessment before
starting any new work. The use of radioactivity has diminished quite
significantly when compared to its use a few years ago, as new nonradioisotopic techniques are employed.
6 RESOURCES
At present all of the usage of unsealed radioactive sources is carried out in
the John Dalton Building. Handling of unsealed radioactive sources is carried
out in the Radiation Laboratory in the John Dalton Tower. There are adequate
storage facilities, and non-porous bench surfaces which are easy to clean.
The floor covering is hard wearing lino, which is coved up the wall surface.
The laboratory has a designated sink for disposal of liquid waste. The sink is
labelled appropriately and monitored as part of the routine monitoring. Any
leakage from the sink is reported immediately to the Property Management
Performance Team (PROMPT). Any work to be carried out by PROMPT is
done after a risk assessment has been carried out, taking into consideration
the amount of waste disposed of, the half life and the energy of emission of
the radionuclides concerned. The laboratory has a suitable contamination
monitor and dose monitors are available from the Health and Safety Unit if
required. Work with P-32 is carried out in a work station behind a Perspex
barrier of adequate thickness.
A Radiation Waste Store is provided for accumulation of radioactive waste.
Funding is allocated and routes identified for the collection and disposal of
radioactive waste.
7 QUALIFIED AND EXPERIENCED STAFF
a) Staff Training
All users of radioactive sources must have received training or have previous
experience that is adequate and sufficient for the work to be carried out. All
Radiation Protection Supervisors receive training on an appropriate Radiation
Protection Supervisors course.
All users of radioactive sources must read and co-operate with all instructions
set out in the local rules.
6
b) Training Records
Training records for courses organised by the Health & Safety Unit will be
kept by the Health and Safety Unit. Other training records will be kept by the
Department concerned.
8 USE AND STORAGE OF UNSEALED RADIOACTIVE
MATERIAL
a) Practices
At present, work with radioactive materials is carried out in the Radiation
Laboratory in the main John Dalton Tower where sources of fairly low activity
may be handled. All new work is only undertaken after a prior Risk
Assessment has been completed.
At present most of the work is confined to P-32, S-35, C-14 and I-125.
b) Appropriate Method
The prior Risk Assessment asks the researcher if non-radioactive methods
have been considered and a reassurance that the quantity of radioactive
material in use is as low as possible and compatible with obtaining good
quality results. The cost of disposal of solid waste is also evaluated, and this
in itself focuses the attention of future users.
c) Ordering and Storage of Radioactive Material
All ordering of radioactive sources is via a central system, where it is possible
to spot an unusually large order or an order for a radionuclide not in normal
use. All laboratories which use radioactive sources have a lockable
refrigerator or a suitable safe. The entrance to most laboratories is via a key
coded door.
9 GENERATION AND DISPOSAL OF RADIOACTIVE WASTE
a) Segregation of Waste
The nature of the work allows segregation of radioactive waste at source. This
also ensures that the volume of solid waste is kept to a minimum most of
which is in the form of counting vials, contaminated tissues and gloves. Liquid
waste is disposed of via the designated sink. Aqueous waste is disposed of as
soon as possible. Organic liquid waste and solid waste is stored in
appropriate containers which are then transferred to the Radiation Waste
Store.
7
b) Estimation of liquid/solid waste
In most of the laboratory techniques currently employed, it has been
established that the vast majority (greater than 95%) of the waste is liquid and
only a small fraction will bind to the protein RNA or DNA. For new techniques,
researchers are asked to carry out preliminary work (e.g. measuring aliquots)
in order to establish the ratio between liquid and solid waste. The results of
this are then used for continued work. It is usually expected that the
radioactivity of the solid waste will be overestimated, however, when
disposing of the waste it is additionally checked using appropriate monitors as
a precaution against underestimation of the radioactivity.
10 ACCUMULATION OF RADIOACTIVE WASTE
All solid radioactive waste is stored in the Radioactive Waste Store. The
security of the contents of the store and its adequacy for space is continually
under review.
Waste can be allowed to accumulate up to 6 months or two years depending
on the half life of the radionuclide. This allows disposal of the two most
commonly used radionuclides, namely S-35 and P-32 to such levels that they
may be disposed of as either non-radioactive waste or very low level
radioactive waste.
Records are kept of all the waste taken to the Store. At the end of each month
current waste is recorded to ensure that the limits set in the authorisation are
not exceeded. When considered necessary, external monitoring of the store is
carried out using dose monitors or environmental film badges. If any leaks are
suspected additional monitoring can be carried out using either contamination
monitors or swabs in a liquid scintillation counter.
11 DISPOSAL OF RADIOACTIVE WASTE
a) Liquid Waste
Liquid waste is disposed of via the designated sink in the Radiation
Laboratory. Small amounts of organic liquid waste are disposed of via a
contractor.
b) Solid Waste
Solid waste may be transferred to one of three contractors but is usually
allowed to decay before disposal as very low level radioactive waste.
8
12 COMPLIANCE WITH THE RADIOACTIVE SUBSTANCES
ACT
a) Open Source Registration
A review is undertaken periodically of the maximum holding levels of various
radionuclides required in each Department and from the Registration each
Department is given a radionuclide allocation limit. This ensures that the
overall registration limits are not exceeded and that the Department has a
sufficient limit for work to be carried out. It is the responsibility of each
Department to make certain that their limits are not exceeded.
Ordering of radioactive sources is via one member of staff who has sufficient
experience to note any unusual radionuclide or quantity of radioactive material
being ordered. He/She has the authority to refuse to sign any order which
breach the registration limits.
b) Waste Disposal Authorisation
Each Department is given an allocation of radioactive material which may be
disposed of each month via each authorised route. The disposal limits are set
out in ‘Receipt, Keeping and Disposal of Radioactive Sources’ which is issued
to any Department wishing to use unsealed radioactive material. It is the
responsibility of each Department to make certain that their limits are not
exceeded.
c) Audit
Annually the RPA carries out an audit of radiation protection issues in the
Departments. All Departments using radioactivity are visited and compliance
with the Radioactive Substances Act and other legislation is checked.
d) Documents
The system of accumulation, record keeping and disposal of radioactive
waste is detailed in ‘Receipt, Keeping and Disposal of Radioactive Sources’
which is issued to any Department wishing to use unsealed radioactive
material.
13 GENERAL
a) Radiological Protection Sub-Committee
The Radiological Protection Sub-Committee which includes the RPA, RPO
and RPS’s will meet at least twice per academic year in order to examine and
update on current radiation issues within the University.
9
b) Reports
The RPA and RPO shall submit annual reports to the University Health &
Safety Committee.
10
14 APPENDIX I RSA3 Assessment
Manchester Metropolitan University
Assessment of Radiological Impact Due to Disposal of Radioactive Waste
Values of Parameters for calculating Committed Effective Dose for inhalation and ingestion and skin dose
Radionuclide
Ingestion: Committed
effective dose per unit
intake ced Sv Bq-1
2.4 x 10-9
Inhalation: Committed
effective dose per unit
intake ced Sv Bq-1
3.2 x 10-9
Contamination: Skin dose
mSv h-1 per 1kBq cm-2
125
I
1.5 x 10-8
7.3 x 10-9
0.021
3
H
4.2 x 10-11
4.1 x 10-11
0
32
P
1.9
Section A
The following critical groups and scenarios are considered.
Critical Group
Sewage worker at the MMU site
Member of public
Scenario
i. Inadvertently ingests 2 litres of sewage at the institute
ii. Spills 10mls of sewage on his hands
Obtains annual drinking supply after sewage treatment
Methodology
It is assumed that the maximum monthly limit of aqueous disposal of radioactive waste is uniformity disposed
of per 20 days per month. The concentration of the radioactivity is uniformly distributed through the site’s
aqueous waste system (relevant to the point of disposal) and a sewage worker inadvertently ingests 2 litres of
this waste.
The waste eventually flows into the sewage treatment works, where further dilution is taken into
consideration..
Calculations
The site is authorised to dispose of the following per calendar month
32
P
0.5 GBq
I
0.1 GBq
3
H
15 GBq
If it is assumed that the discharges are uniform throughout the month (20 days/month), then
125
Daily disposals
32
P
25 MBq
125
I
5 MBq
3
H
750 MBq
The main out flow points where radioactivity is used if from the John Dalton Campus, where on average,
3550m3 of water is disposed of per month.
11
Therefore the daily concentration in the waste from the Institute per m3 would be
32
P
212 kBq
125
I
42 kBq
3
H
6356 kBq
A person inadvertently drinking 2 litres from this discharge would consume
32
P
424 Bq
125
I
85 Bq
3
H
12712 Bq
and his committed effective dose is calculated by multiplying the above numbers with the ced per unit intake.
This works out to
32
P
(2.4 x 10-9 x 106) x 424 µSv
125
I
(1.5 x 10-8 x 106) x 85 µSv
3
H
(4.2 x 10-11 x 106) x 12712 µSv
This equals 2.82 µSv
The waste eventually flows into the Davyhulme Sewage Works. The daily average flow of waste through the
sewage works is about 180000m3. The concentration of radioactivity per m3 at the sewage works is::
32
P
I
3
H
125
139 Bq
28 Bq
4167 Bq
A person obtaining his/her annual drinking supply from this source would consume 0.6m3 annually and his
committed effective dose would be, calculating as above:
This equals 0.56 µSv
The sewage at the Davyhulme Waste Water Treatment Works is treated by conventional activated sludge
followed by ammonia removal in a BAFF plant. Sludge is typically 6% of dry solids, which is transferred by
pipeline to Shell Green facility where it is pressed into cake prior to incineration. Grit is taken to landfill.
Treated water follows into the Manchester Ship Canal
The concentration of radioactivity prior to treatment plant is 0.0044 Bq/gm. It is highly unlikely that the
concentration in the sludge or grit would be greater than 0.4Bq/gm
12
External Doses
As 32P comprises of the majority of the waste and it is a beta emitter, and only 100MBq of 125I are disposed of
per month, external doses are not considered. However, a sewage worker working outside MMU might
inadvertently spill sewage on his hands. Therefore dose to the skin is considered. Note that skin dose due to
3
H is 0
Concentration of activity at sewage leaving MMU is
32
P
I
125
212 Bq l-1
42.4 Bq l-1
and if it is assumed that 10mls of this sewage is spilled on a hand of area 100cm2, then it can be shown
that the skin contamination would be
32
P
125
I
2.12 x 10-5 kBq/cm2
4.24 x 10-6 kBq/cm2
and the total skin dose works out to be just over 0.04µSv/hr
13
Section B
The following critical groups and scenarios are considered.
Critical Group
Scenario
Sewage worker at the sewage treatment i. Inadvertently ingests radioactivity from the sewage
works
ii. Inadvertently inhales radioactivity from the sewage
Methodology
As detailed in reference 2
Calculations
Ingestion
Hing = Cunf m Ding O
where Hing is the ced for ingestion of radionuclides (Sv y-1)
Cunf is the conc. of a radionuclide in a untreated sewage (Bq kg-1 or Bq l-1, assuming a density of 1
tonne m-3)
m is the intake rate for inadvertent ingestion of sewage (kg h-1) (5 x 10-5)
Ding is the cede per unit intake by ingestion (Sv Bq-1)
O is the occupancy ( 2000 hours)
Cunf : At the sewage plant, 180,000 m3 per sewage flows per day. This is equivalent to 1.8 x 108 litres per day.
Cunf, and the ced is then
32
P
125
I
3
H
0.139 Bq l-1 leading to a ced of 3.33 x 10-11 Sv y-1
0.028 Bq l-1 leading to a ced of 4.17 x 10-11 Sv y-1
4.167 Bq l-1 leading to a ced of 5.00 x 10-12 Sv y-1
This sums to a total of 9.25 x 10 -11Sv y-1 ie 9.25 x 10-5 µSv y-1
Inhalation
Hinh = Cunf sr V Dinh O
where Hinh is the cede for ingestion of radionuclides (Sv y-1)
Cunf is the conc. Of a radionuclide in a untreated sewage (Bq kg-1 or Bq l-1, assuming a density of 1
tonne m-3)
sr is the re-suspended sewage load (0.1 mg m-3)
Dinh is the cede per unit intake by inhalation (Sv Bq-1)
O is the occupancy (2000 hours)
Using Cunf from above (ingestion scenario) and ced per unit intake of inhaled activity, the ced due to
inhalation is:
This sums to a total of 1.96 x 10-13 Sv y-1 ie 1.96 x 10-7 µSv y-1
14
Summary
1. It has been shown that a sewage worker inadvertently consuming 2 litres of waste from the MMU site
would receive a committed effective dose of 2.82 microsieverts.
2. If he were to spill 10mlson his hands, he would receive a skin dose of 0.04 microsieverts for the first
hour, when it is assumed that he would wash his hands.
3. A person obtaining his annual supply of drinking water from the Manchester Ship Canal, where the
waste from MMU goes to, would receive a committed effective dose of 0.56 microsieverts.
4. A sewage worker at Davyhulme Sewage Treatment Works would receive a annual committed effective
dose of 9.25 x 10-5 microsieverts due to inadvertent ingestion and 1.96 x 10-7 microsieverts. due to
inadvertent inhalation due to the spray.
5. As the vast majority of radionuclides do not emit gamma radiation, his external dose is not considered.
6. The concentration of the affluent would be approximately 0.0044 Bq/g.
7. It is pointed out that the treated water from the Davyhulme Treatment Works does not constitute a
potable supply, and therefore some of the assessments are very pessimistic.
8. Because the concentration of radioactivity in the affluent is so low and all the doses above so small, no
consideration has been given to marine life or the uptake of the radioactivity by plant life if some part
of the sludge is used for the purpose of manure.
References
1. NRPB-R162: Doses from Intakes of Radionuclides by Adults and Young People.
2. NRPB-M744: Assessment of the Radiological Consequences of Accumulation and Disposal of Radioactive
Waste by Small Users of Radioactive Materials
3. Radiation Protection Dosimetry
15