RADIATION SAFETY

Phil Facey Lead Superintendent Radiographer Nuclear Medicine and PET University Hospital of Wales Honorary Lecturer University of the South West of England

RADIATION IS AROUND US ALL THE TIME

Medical

Cosmic 10%

Radon gas from the ground

Ground and buildings14%

50%14%

Medical Radiation

u Ionizing radiation even at low doses is potentially capable of causing serious and lasting biological damage

u There is great care to control the amount of radioactivity used in diagnostic imaging

1 in a Million1 chest x-ray 1 in a million chance of radiation induced cancer

Equivalent fatal risks (1 in a million)u 1.5 cigarettes (lung cancer)u 300miles in a car (fatal accident)u 10 miles on a bike (fatal accident)u 6 minutes in a canoe (fatal accident)u 1000miles in an aeroplane (fatal accident)

NRCP 1978

Unitsu Absorbed dose – Gray (Gy)u Dose Equivalent – Sievert (Sv)u Radioactivity - Becquerel (Bq)

Radiology Department

Diagnostic Radiologyu X-Raysu Fluoroscopy – Barium Studies,

Interventional Procedures

Nuclear Medicineu V/Q scans, Bone scans, Renograms, u Therapy

Radiology Department

Nuclear Medicineu Department split into 2 Areasu Supervised Area – may or may not

contain radioactivityu Controlled Area – contains a radioactive

source

Radiology Department

You should never walk through a Nuclear Medicine Department as a short cut to other departments

You can enter only under instructions from staff

Radiology Department

Radiation Protection Supervisorsu Supervise radiation in their own

departmentu Their names will be displayed on the

doors marked with radiation signs

Medical Radiation

Radiation could be present in rooms marked with warning signs

Medical Radiationu Or by illuminated signs over doors

u If the words DO NOT ENTER are lit DO NOT ENTER under any circumstances

Medical Radiation

Problems working in Radiation areas can be split into 2 categories

u Due external radiationu Due to contamination

Medical Radiation

In the X Ray rooms and Radiotherapy rooms

u The problem is due to External Radiation

u The rooms are not left radioactive and neither is the patient

SOURCEOFRADIATION

X RAYS AND RADIOTHERAPY

Medical Radiation

Nuclear Medicine Roomsu Problems can be due to:u External Radiationu Contaminationu The room can be radioactive even when

empty

Medical Radiation

Radiation Hazards on the Wardu Portable Radiography

u Nuclear Medicine Patients

Medical Radiation

Portable Radiographyu X Ray examinations performed outside the

department on wards/theatre u Radiation only produced when Radiographer

presses exposure buttonu Always follow instructions u Keep a safe distanceu Wear lead protection if involved in holding

patients

Medical Radiation

Nuclear Medicine u Patients returning to the ward after

being administered with a radiopharmaceutical

u Ward information sheet only given when a patient has been administered with a dose above

Medical Radiation

Nuclear Medicine patients are given u a) an injection of radioactivity or u b) asked to breathe in a gas or u c) asked to eat prepared food

Medical Radiation

RADIONUCLIDESu Maximum Energy

u Half Life (T1/2)

99mTc (Technetium)u 140KeV

u T1/2 - 6 hours

NUCLEAR MEDICINE PATIENT

SOURCE OF RADIATION

rays

BUT AS WELL AS THE EXTERNAL RADIATION THERE IS ALSO A RISK OF CONTAMINATION

The main way the radioactivity leaves the body is in the urine.

Hence a spill of urine can make the room radioactive.

A spilt vial in the Nuclear Medicine labs can make the room radioactive.

An additional problem, ONLY for the in-patients treated with high amounts of radioactivity for Radiotherapy, is that the radioactive contamination can come from their sweat as well as their urine. Hence anything they touch or anywhere they walk can become radioactive

NUCLEAR MEDICINE THERAPY PATIENT

NUCLEAR MEDICINE THERAPY PATIENT

SOURCE OF RADIATION

rays

NOT CONTAMINATING THINGS IN ROOM

wardrobe

NUCLEAR MEDICINE THERAPY PATIENT

SOURCE OF RADIATION

rays

NOT CONTAMINATING THINGS IN ROOM

wardrobe

NUCLEAR MEDICINE I THERAPY PATIENT

SOURCE OF RADIATION

rays

CONTAMINATING THINGS IN ROOM

wardrobe

NUCLEAR MEDICINE 90Y THERAPY PATIENT

Blood Supply of Liver CancerBlood Supply of Liver Cancer

SIR-Spheres in Liver CancerSIR-Spheres in Liver Cancer

This is why patients are admitted so that they do NOT contaminate their own home.

Even when they leave, the rooms will be radioactive. It is not safe for people to go into these rooms unless they know what they are doing or until notified by the Nuclear Medicine Department

NUCLEAR MEDICINE THERAPY PATIENT

There are 3 basic steps you can take to ensure the Radiation dose you receive while working is as low as possible

TIME near a radiation source

DISTANCE near a radiation source

SHIELDING near a radiation source

-KEEP AS SHORT AS POSSIBLE

-KEEP AS FAR AWAY AS POSSIBLE

-USE IF ADVISED TO DO SO

You may also be advised to wear Protective clothing

Gloves,

Plastic apron,

Overshoes,

Lead apron

This will prevent the radioactive material from getting on your skin or clothes or radiation from reaching your body

Personal Radiation Monitoringu Film Badges You may be required to wear a film

badge. It is important you wear it throughout the examination

Personal Radiation Monitoring

u Film Badges Under the Health and Safety at Work Act 1974 You can be prosecuted if you fail to wear, look after or return your film badge

Personal Radiation Monitoring

u Finger Badges

Records radiation dose to hand and fingers

Personal Radiation Monitoringu Personal Dosimeters

Give an immediate dose reading and alerts you to high radioactivity

Radiation Safety

u Always follow instructionsu Observe and take note of door signsu Time u Distance u Shieldingu Wear Personal Radiation Monitors if

required

PRESENT DAY RADIATION EXPERTS

Any Questions ?