NM Flashcards
For Tc-99m, when does IRR17 apply?
> 100 Bq/g and > 10 MBq
What is included in a risk assessment?
- description of work
- nature of hazard (energy, activity, half-life)
- exposed persons
- contamination
- control measures
- accidents (spill, ingestion, needlestick)
- location
- doses and dose rates (routine and accidents)
When must local rules be used?
for controlled areas
What must be included in the local rules?
- description of area
- working instructions to restrict exposure
- access arrangements
- dose investigation levels
- name of RPS
- contingency plan
What else may be included in the local rules?
- testing and maintanence
- dosimetry of staff
- audit and compliance
- details of RPA
When is a contingency plan required?
where the accident could result in an exposure which exceeds normal planned exposures
Examples of when a contingency plan is required
- spills
- personal contamination
- loss of source
Who should be notified of staff over-exposures?
HSE
Effective dose
sum of equivalent doses to the exposed organs or tissues multiplied by tissue weighting factors
helps estimate risk from stochastic effects
How can percutaneous absorption be minimised?
- PPE (gloves, apron, arm coverings)
- quick removal of contaminated
- dose monitoring is important
What should you do after a needlestick injury?
- wash area with soap
- encourage bleeding
- contamination monitoring
How to minimise dose from extravasation?
- check lines with saline
- elevate the arm
- squeeze stress ball
Legislation involved in radionuclide therapies
- IRR17 (staff and public)
- IRMER17 (patient and ARSAC)
- EPR (licence and waste)
What is included in a therapy risk assessment?
- external dose rate from patient
- excretion factors
- contact restrictions
- visitors
How are restriction times calculated?
- post-administration dose rates at different distances
- clearance curves
- administred activity
- dose constraints
Why are restriction times for younger children longer?
After the restriction period is over, they tend to have more prolonged and closer contact with the patient
What is a sealed source?
a non-dispersable source
flood source for QA
What is a high-activity sealed source?
sealed source for which the quantity of the radionuclide is equal to or exceeds the relevant quantity value
brachytherapy, requires additional security measures
What is a open source?
one which can be dispersed but is not waste
Tc-99m vials, Mo/Tc generator
What is radioactive waste?
any open or sealed source which can no longer be used and above a certain threshold
What is the key legislation for the control of RAM?
Environmental Permitting Regulations 2016
Enforced by the Environmental Agency
What does EPR govern?
- the amount of RAM which can be held for a particular purpose
- how it is kept and used
- how RAW is disposed of
When is a source no longer a source?
- after patient administration
- any source moved to accumulating waste
- liquid sources being discharged as waste to drains
- open sources transferred to another permitted holder
Whic category is least hazardous under EPR?
category 5 sealed source
What is included in a EPR permit?
- permitted activities (storage and use of RAM, accumulation of RAW, production, transport)
- permitted radionuclides and max activity limits
- RAW (activity, volume limits, accumulation period)
- waste disposal routes (annual/monthly activity limits, disposal route)
What are Publicly Available Permits for?
unsealed source and associated waste
must display
What are Standard Rules Permits for?
all sealed sources taken together must fall into category 5 and don’t accumulate waste
do not display permit
What are Security Permits for?
sealed source and associated waste
cat 1-4
Control measures to restrict unauthorised access to open sources held under a “Publicly Available” permit
- sources under continous supervision
- suitable container in a suitable store
- hazard warning signage
- locks
- training of staff to support
Actions “Publicly Available” permit conditions require to do if radioactive material has been lost or stolen
- inform police and EA
- recover the sources as far as is reasonably practicable
- report the situation to the EA in writing ASAP
What is an orphan source?
a source which has fallen out of regulatory control