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