Personal Monitoring (lecture 2) Flashcards
Why are staff monitored? (3)
It is a requirement of the legislation (IRR’17) that all work with ionising radiation must be risk assessed, which requires an assessment of doses
It ensures that staff and systems are safe
It ensures that staff don’t exceed any dose limits
What are the responsibilities of employers relating to staff dose monitoring? (9)
Decide which staff should be monitored and how
Make decisions on requirements for classification
Set dose investigation levels
Seek RPA advice on compliance with legislation
Supervise wear, distribution, and return of dosimeters
Check results as well as performing and documenting investigations
Retain dose records for 2 years
Responsible for non-classified worker records
Appoint and liaise with ADS
What is an ADS? (6)
An approved dosimetry service is approved for one or more of:
Assessment of internal or external dose
Record keeping
Accident dosimetry
Approval process: documentation checks and visit from HSE Inspector
Regular successful performance tests needed to retain approval for external assessment services
Responsible for dosimetry assessment, record keeping and CIDI transfers for classified workers
Name some differences in personal monitoring, between classified and non-classified staff. (5)
Non-classified staff do not require ADS monitoring. Classified workers do.
Monitoring of non-classified staff is used to check that working practices are safe and effective.
Classified staff dose records are held by the Central Index of Dose Information (HSE).
Classified staff must keep a passbook filled when working with radiation for multiple employers.
Classified workers require an annual medical check to ensure that they are still fit to work as a classified worker.
Explain Hp(d)
Hp(d) the personal equivalent dose, where d is the depth. This is measured in mSv.
Give some common values of d (in Hp(d)) and what they are used to assess.
When d=10mm, this is considered to give a whole body dose.
When d=0.07mm, this is considered to give a skin dose.
Give two examples of personal dosimeters (not including dose ranges), what they are made from, and their uses.
Thermoluminescent dosimeters (TLDs) are used for WB and extremity monitoring. Commonly made from lithium fluoride.
Optically stimulated luminescence dosimeters (OSL) dosimeters are use for WB and LARGE extremity monitoring (such as ankles and wrists, not fingers). Commonly made from aluminum oxide crystals. Can be read more than once.
What are the dose ranges of a TLD?
1microGy to 10Gy. Reusable.
What are the dose ranges of an OSL dosimeter?
10microGy to 100Gy.
What are the responsibilities of the employer WRT personal monitoring results? (2)
Employers have the ultimate responsibility for recording and checking reports
Employers are responsible for identifying results that require investigation, and then documenting the investigation and findings
What is the CID, and which body is responsble for it.
Central Index of Dose Information, the HSE.
The CID is where classified worker’s results are kept.
