Radiation Protection Flashcards
All exposures are potentially harmful and must be: (3)
- Justified
- Optimised (ALARP)
- Below legal dose limits (not in IRMER)
Who has most responsibility for providing protection?
Employer
Who does IRR17 protect?
Staff and general public (not patients)
Who is IRR17 enforced by?
HSE
Who advises the employer?
Radiation protection advisor
Who oversees practice in clinical areas?
Radiation protection supervisor
What is needed for new procedures?
Radiation risk assessments
What do local rules do?
Tell staff how to work in controlled areas
At what exposure dose do staff need to be classified?
If they receive >3/10 of any dose limit (>6mSv whole body, >150mSv skin)
or >15mSv eye dose
Employee annual dose limit: Whole body
20mSv
Employee annual dose limit: Skin and extremities
500mSv
Employee annual dose limit: Eye
20mSV
Trainee (<18yo) annual dose limits: Whole body
6mSv
Trainee (<18yo) annual dose limits: Skin and extremities
150mSV
Members of the Public annual dose limits: Whole body
1mSv
Members of the Public annual dose limits: Skin and extremities
50mSv
Members of the Public annual dose limits: Eye
15mSv
Specifications of controlled areas (4)
- precautions needed to avoid significant exposure
- dose likely to be >3/10 of any dose limit
-Local rules
-Need RPS to enforce local rules
Specifications of supervised areas (3)
- lower risk than controlled area
-when work reviewed periodically/if annual dose likely >1mSV
-DO NOT require local rules or RPS
When do staff become classified?
If they are likely to receive 3/10th of any dose limit
-e.g. 6mSV for whole body, 150mSV for skin/extremities
What is the dose level for foetus of worker during pregnancy?
<1mSv
Women must declare in writing to employer if pregnant (T/F)
True
IRR 2017 requires that radiation doses must not exceed legal limits (T/F)
True
IR(ME)R 2017 requires that radiation doses to patients must not exceed legal limits (T/F)
False
No legal limit, just have to optimise and justify exposures
Who does IRMER protect?
Patients/persons having a medical exposure
According to IRMER what is the employer responsible for?
responsible for providing a radiation protection framework
Define the referrer
provides clinical information to support the request for medical exposure
Define the practitioner
registered health care professional who is entitled to justify and take responsibility for an individual exposure
Define the operator
any person entitled to carry out practical aspects of a medical exposure
Define the medical physics expert
State registered professional who can advise on regulatory compliance and provides radiation dose measurements/calculations
IRMER -
1)Who is justification carried out by?
2) How do they demonstrate this has been done?
1) practitioner
2) Authorisation
IRMER - Optimisation
What is a DRL?
DRL indicate achievable patient exposure factors, guidelines for average sized patients, established by the employer
IRMER Licences-
nuc med and/or PET exposures can only take place when the employer and practitioner have BOTH been issued licenses (T/F)
True
IRMER Licences-
Practitioner licenses can be issued to consultants and trainees with sufficient training and experience in nuc med
False - only consultants with sufficient training and experience in nuc med can hold a practitioner licence
Define accidental exposure
exposure when none was intended
Define unintended exposure and give 3 examples
dose delivered was significantly different from planned
Wrong body part, wrong pharmaceutical, wrong dose
IRMER T/F
The outcome of each exposure must be recorded
True
IRMER:
Must be provision for carrying out of clinical ____
Audit
IRMER: Radiation equipment
1) Must be subject to a __ programme
Must be subject to a QA programme
IRMER: Radiation equipment:
2) Employer must maintain an inventory of ______ ______ _______
Employer must maintain an inventory of all radiation equipment
What do the Radioactive Substances Legislations apply to? (4)
- keeping and use of radioactive materials
- Accumulation and disposal of radioactive waste
- Both sealed and unsealed radioactive sources
- Nuclear med and PET/CT
Sources of radioactive waste in NM/PET
Solid - contaminated syringes/vials
Liquid - patient excretions
Gas - radioactive gasses and aerosols
One nuc med permit is required for both open and sealed sources of radiation (T/F)
False - seperate permits are required for ‘open’ and ‘sealed/closed’ sources
Nuc med permits are valid for all hospitals within a trust (T/F)
False - a separate permit is required for each site
Disposal of solid waste - describe how to dispose of short half life solid radioactive waste
-Store in sharps bin in shielded waste store
- radioactivity decays to background levels over time, then dispose of as ordinary waste
Disposal of solid waste - describe how to dispose of long half life solid radioactive waste
Must be disposed of by waste contractor
Disposal of Liquid Waste-
What is main source of liquid waste?
Patient excretion
What are general percentage estimations of liquid waste for:
1) 99mTc
2) 18-FDG
1) 99mTc - 40% excretion
2) 18-FDG - 20% excretion
eg bone scan Tc99m injected = 600MBq
Liquid waste excreted 600 x 0.4 = 140MBq
Annual background radiation dose average =…?
2.2/2.3mSv
Members of Public Dose Limits: Eyes, Skin/extremities and Whole Body?
15mSv, 50mSv, 1mSv
Trainees under 18 Dose Limits: Eyes, Skin/extremities and Whole Body?
15mSv, 150mSv, 6mSv
Employees Dose Limits: Eyes, Skin/extremities and Whole Body?
20mSv, 500mSv, 20mSv
How is the incident notification period defined?
It is the time from when the incident is discovered to the time notified.
The notification period is defined as a maximum…
2 weeks
What is the period in which an investigation of an incident must be submitted
Within 12 weeks
Can the notification and investigation of an incident be submitted simultaneously
No
What is the dose restriction to a pregnant employee (and her foetus)
dose to foetus <1mSv for the remainder of the pregnancy
What are the IRMER (2017) dose limits
No dose limits but all medical exposure must be JUSTIFIED and OPTIMISED
What 3 limitations could be the reason that an area is an controlled area
1. Need for ???
2. Dose exceeding???
3. External dose rate exceeds???
- need for PPE, local rules and an RPS
- Or equivalent dose of >3/10 of any relevant dose limit
- External dose rate exceeds 7.5 uSv/hr over working day
What are the dose thresholds for a supervised area (2)
- Person working in area likely to receive a dose of >1mSv/year
- Or equivalent dose of >1/10 of any relevant dose limit
Classification doses (for workers to become classified)?
6mSv for effective dose, 150mSv for hands/extremities, 15mSv for eyes
“Investigation level” of dose is set by employer to investigate after a specific dose, must be less than (…?) and is usually around (…to…)
Must be less than 15mSv
Usually 1-4mSv
IRMER Licenses are issued by…?
Administration of Radioactive Substances Advisory Committee (ARSAC)
IRMER licenses from ARSAC must be reviewed every…?
5 years
2 measurements for DRLs in X-rays/fluoro?
ESD
DAP
How are DRLs measured in CT?
CTDI or DLP
XR Abdo AP DRLs? (2)
ESD = 4.0
DAP = 2.5
XR Chest AP DRLs? (2)
ESD = 0.2
DAP = 0.15
XR Lumbar spine AP DRLs? (2)
ESD = 6
DAP = 1.5
XR Lumbar spine LAT DRLs? (2)
ESD = 10
DAP = 2.5
XR Knee DRL (ESD)?
0.3 ESD
CT Head CTDI and DLP?
CTDI = 60
DLP = 1000
CT CAP DLP?
1000
CTPA ESD and DLP?
ESD = 13
DLP = 440
CT KUB ESD and DLP?
CTDI = 10
DLP = 460
What level of significant dose would be reportable, for exposure category of:
Intended Dose less than 0.3mSv
Over 3 mSv
What level of significant dose would be reportable, for exposure category of:
Intended Dose 0.3-2.5mSv
x10 of intended dose
What level of significant dose would be reportable, for exposure category of:
Intended Dose 2.5-10mSv
> 25mSv
What level of significant dose would be reportable, for exposure category of:
Intended Dose >10mSv
x2.5 intended dose
Radioactivity permits have a list of conditions, including the appointment of a…
Radioactive Waste Advisor
ESD equation related to air kerma?
Entrance surface dose = air kerma x back scattered factor
What does the IRMER 28 day rule state?
Normal procedures can be performed if a woman 12-55yrs has had a normal period within last 28 days
What is the IRMER 10-day rule for women?
Any non urgent procedure can be performed within 10 days of the start their period unless high dose pelvic exam
True/false: medical exposures provide a higher radiation dose to the public than doses from nuclear weapons testing
True
IRMER regulations are enforced by…?
The CQC
T/F- IRMER requires the employment of a radiation protection advisor
False
This is IRR
The Radioactive substances act 1993 concentrates on the risk to the…
Public and environment from radionuclides
Under IRR who has overall responsibility for keeping patient dose as low as reasonably practical?
The employer
True/false: The practitioner is the only person allowed to authorise an X-ray exposure
False