do not adjust your set. radiation safety induction for radiology registrars john saunderson...
TRANSCRIPT
Do not adjust your set
www.hullrad.org.uk
Radiation Safety Induction
for Radiology Registrars
John SaundersonRadiation Protection Adviser
CHH ext 76-1329
Ionising radiations• x-rays gamma rays (-rays) beta particles () electron beams
Not ionising radiations
• lasers ultraviolet (UV) infrared (IR) ultrasound MRI
Ionising / Non-ionising
Radiation hazards
700 CANCER CASES CAUSED BY X-RAYS
X-RAYS used in everyday detection of diseases and broken bones are responsible for about 700 cases of cancer a year, according to the most detailed study to date.
The research showed that 0.6 per cent of the 124,000 patients found to have cancer each year can attribute the disease to X-ray exposure. Diagnostic X-rays, which are used in conventional radiography and imaging techniques such as CT scans, are the largest man-made source of radiation exposure to the
general population. Although such X-rays provide great benefits, it is generally accepted that their use is associated with very small increases in cancer risk.
30 January 2004
Average X-ray exam dose = 0.5 millisieverts ► 1 in 40,000 risk
UK Radiology = 46 million X-rays per year (2008)
Basic Principals of Radiation Protection
• Justification– Benefit > risk
• Optimisation– Doses as low as reasonably achievable
• Limitation– Absolute legal limits for staff and public– Reference levels as guidance for patients.
Regulations
• Ionising Radiations Regulations 1999 (IRR99)– Justification, optimisation, limitation– Local rules, radiation protection supervisors
• Ionising Radiation (Medical Exposure) Regulations 2000 (IRMER2000)– Referrers, practitioners, operators– Justification & optimisation
• Medicines (Administration of Radioactive Substances) Regs 1978 (ARSAC)– Nuclear medicine
Organising radiation safety (IRR99)
Controlled Areas
Local Rules
Radiation Protection Supervisor
Radiation Protection Adviser
Radiographer.
19/04/23
Controlled Area
• No-one may enter a controlled area unless
1. They are a classified person
2. They are following the local rules/system of work for that area
IRMERIonising Radiation (Medical Exposures) Regulations 2000
• Referrers – allowed to request medical exposure– Trust decides who can e.g. GP, consultant, etc.
• Practitioners– Justifies X-ray - decides there is net benefit– Trust decides who can e.g. radiologist
• Operator– Performs “practical aspects”– Trust decides who can e.g. radiographer, technician
.
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Medicines (Administration of Radioactive Substances) Regs 1978
(“MARS” / “ARSAC”)
• “No person shall administer to a human being (otherwise than to himself) any radioactive medicinal product unless he is doctor or dentist holding a certificate issued by the Health Minister for the purposes of section 60 of the Act in respect of radioactive medicinal products (hereinafter referred to as a “certificate”) or a person acting in accordance with the directions of such a doctor or dentist.” .
Radiation in hospitals
• Radioactive substances– nuclear medicine– pathology– radiotherapy
• X-ray sources– Radiology– Radiotherapy– Pathology .
Leakage
Basic Principles
Time
Distance
Shielding
Distance
•Double distance = 1/4 dose
•Triple distance = 1/9th dose.
Shielding
Shielding
Typical Transmission through Shielding (90 kV)
• 0.25 mm lead rubber apron 8.5%• 0.35 mm lead rubber apron 5%• 2 x 0.25 mm apron 2.5%• 2 x 0.35 mm apron 1.0%
•Double brick wall 0.003%•Plasterboard stud wall 32%•Solid wooden 1” door 81%•Code 3 lead (1.3 mm) 0.1%.
Lead Apron Storage
• Always return to hanger• Do not
– fold– dump on floor and run
trolleys over the top of them!!!
• X-ray will check annually• But if visibly damaged,
ask X-ray to check them.
The End