Radiography H&S Flashcards
Main responsibilities of employer with respect to H&S Act 1974
Duty to protect health, safety & welfare of employees & others who may be affected by their business
- whatever reasonable practicable to control/minimise risk
Duty to assess workplace risk
- provide info re. potential risk & protective measures in place
- instruct/train employees how to deal w/& minimise potential risks
Duty to keep up to date w/ changes in h&s regs
- must have h&s policy in place which employees must be made aware of
- revise policy when necessary
What is the Ionising Radiations Regs 1999?
Law governing use of radiation & radioactive materials
Name of secondary revised booklet explaining IRR 1999
Approved code of practice for the protection of persons against ionising radiation arising from any work activity
What are the requirements of IRR 1999?
Requires that practices assess risks of radiography
- ID of measures to restrict radiation exposure to staff & other persons
- Any staff involved in radiography must have read & signed local rules
- Suitable PPE provided, stored properly & examined regularly
Literature introduced by BVA re. Ionising radiation
- name
- year
- explains…
- aims…
- covers…
Guidance notes for the safe use of ionising radiation in veterinary practice 2002
- explains requirements for vet profession
- aims to minimise radiation doses
- covers equipment/personnel/procedures
Principles of radiation protection
- clinical justification
- minimal exposure time, distance & shielding
- no dose limit should be exceeded
What is an RPS?
Who may this be?
Radiation protection supervisor
Appointed by practice
Principle/senior partner/head RVN
What is an RPS responsible for?
- Ensuring that radiography carried out safely, in accordance w/regs, & that local rules are obeyed
- (do not need to be present for every r.exam)
What is an RPA?
Requirements to be RPA
- Radiation protection advisor
- must have diploma in vet radiology
- must hold certificate of competence from appropriate issuing body
What is an RPA responsible for?
- Providing advice on radiation protection & demarcating of controlled area
- Drawing up local rules & written systems of work
Controlled area requirements
- Specific room w/thick +/- reinforced walls (lead ply/barium plaster)
- Standing at least 2m from p.beam
- Demarcated w/labels & warning notices
- Warning sign at entrance
- Red light indicating Rx in progress
- X-Ray lights visible from c.panel; on/off status
- Ceases to be controlled area when machine disconnected from power
Local rules:
Who draws them up?
Where should they be & be given to?
- Drawn up by RPA
- displayed in x-ray room
- provided to anyone involved in rx
What do local rules cover?
- equipment & procedures
- restriction of access
- methods of restraint
- assessment of max dose received
- written system of work
What is the written system of work?
- section of local rules
- gives step by step guide to procedures to be followed when carrying out rx
What are the effects of x-rays/ionising radiation?
- hazardous to living tissues
- harmful effects which may be both immediate & delayed
- results in chemical changes
- May lead to physiological change/injury
What must be included when recording exposures?
- date
- patient ID & description
- view
- restraint means
- exposure factors
- image quality
- personnel involved
Requirements for Rx PPE
- made of rubber impregnated w/lead
- routinely examined for cracks/damage
What does Rx PPE protect against?
- scatter radiation
- not p.beam
What is LE?
What does it relate to?
- lead equivalent
- thickness of pure lead
- PPE
Lead apron requirements
- must cover trunk
- esp. gonads
- reach mid-thigh
Lead apron minimum LE
0.25mm
What should not be done w/lead gloves?
Placed w/in p.beam
Lead glove minimum LE
0.35mm
Where should dosemeter be worn?
Who should wear dosemeter?
- on trunk, under lead apron
- anyone involved in Rx
- only worn by person to which it’s issued
How often should dosemeters be sent for reading?
- every 1-3 months
- case-load dependant
What must not be done w/dosemeters?
- washed/tumble dried
- left in controlled area when not in use
- exposed to heat or sunlight
What do thermoluminescent dosemeters contain?
radiosensitive lithium fluoride crystals
How do thermoluminescent dosemeters work?
when exposed to radiation the lithium fluoride crystals are rearranged, storing energy
How are thermoluminescent dosemeters read?
- lithium fluoride crystals are heated
- give off light proportional to amount of stored energy
- provides quantitive reading
Which public authority monitors readings from dosemeters?
What else do they do?
- National Radiological Protection Board
- conducts research on radiological protection & reports to governmental departments
Dose limit definition
Amount of radiation thought not to pose a greater risk to health than radiation encountered in everyday life
Dose limits for employees of 18yrs or over
Whole body: = 50mSV
Individual organs/tissues: = 500mSV
Ocular lens: = 150mSV
Does limits for trainees under 18yrs
Whole body: = 15mSV
Individual organs/tissues:= 150mSV
Ocular lens: = 45mSV
Dose limits for any other person
Whole body: = 5mSV
Individual organs/tissues: = 50mSV
Ocular lens: = 15mSV
Who should never be present for radiography?
- those <16yrs
- owners
Rules regarding primary beam
- should be directed vertically
- must be collimated to smallest area possible
- must be entirely w/in film borders
What is the approved code of practice regarding restraint?
Only in exception circumstances should a patient or animal undergoing a diagnostic examination be supported or manipulated by hand
Examples of exceptional circumstances allowing manual restraint
- severe illness
- severe traumatic injury
- congestive heart failure
- ruptured diaphragm
How often should an x-ray machine be serviced?
Annually
How may cracks in PPE be identified?
X-ray PPE
