Radiation Protection

Internal/External Hazard Internal hazard arises through ingestion or inhalation of a radiation material – not a problem in radiology.

Internal/External Hazard External hazards Arise from exposure to external sources. X-ray sets, emissions from sources etc

Reducing Radiation Dose from external hazard TIME DISTANCE SHIELDING PERSONNAL PROTECTION CLOTHING

Reducing Radiation Dose from external hazard - TIME The longer you are exposed to a field of ionising radiation the higher the dose you will receive. Double to time double the dose

Reducing Radiation Dose from external hazard - DISTANCE The nearer you stand to an source of radiation the higher the dose – so stand away! Double the distance quarter the dose

Reducing Radiation Dose from external hazard - Shielding Lead shielding can be used to attenuate X-rays Room shielding Screens Protective clothing

Shielding Need to know type of radiation Plan to use Local Shielding Nuclear Imaging uses g radiation Radiochemical Labs use b radiation Plan to use Local Shielding May also need Wall Shielding

Local Shielding 1 Vial Shielding b emitters - Perspex Vial shields & Storage g emitters - Tungsten Vial shields & lead-lined box for Storage

Vial Shielding b emitters

Vial Shielding g emitters

Local Shielding 2 Nuclear Medicine Syringes g emitters - Tungsten syringe shields lead-lined box for Storage

Syringe Shields g emitters

Local Shielding 3 L- Bench Shielding g emitters - Lead- lined shields & Lead-glass b emitters - Perspex L shields

Lead L- Bench g emitters

PET Dispensing Station

Perspex L Bench b emitters

Local Shielding 4 Radioactive Waste Shielding g emitters - Sharps bins & Lead-lined containers b emitters - Perspex waste containers, often lined with polythene bags

Sharps bins & Lead-lined containers g emitters

Perspex waste containers b emitters

Wall Shielding Often unnecessary for labs However, same principles employed for X-ray rooms should be applied to assess requirements for Radiochemical Laboratories

Room shielding Lead glass viewing window Lead lined plaster board

Reducing Radiation Dose from Internal hazard PERSONNAL PROTECTION CLOTHING (Training, technique, experience)

Personal Protective Equipment

Radiation protection in X-ray

Personal Monitoring Why monitor non-classified workers? Not likely to receive > 3/10 relevant dose limit (e.g. effective dose > 6 mSv / yr) How do you prove this? Easiest way is to provide ongoing monitoring

Thermoluminescent dosemeters Measurement range 0. 1 mSv to 5 Sv Only issued if risk assessment concludes they are required

Electronic Dosimeters Give an instant reading of dose. Measurement range 0.001 mSv to 1 Sv

Other Monitoring Extremity Eye - tlds Internal rings - tlds or electronic Eye - tlds Internal e.g Iodine uptake doserate measurements swabs samples

Contamination Spilt or misapplied radionuclides adheres to or lies on surface of skin, clothing, equipment or furniture. Spills give rise to: external radiation activity entering body via ingestion inhalation absorption leading to internal radiation

Instrumentation for detecting ionising radiation

Gas based detectors – Geiger- Muller counter, GM tube, or Geiger counter Scintillation detectors - Solid state Liquid

Gas filled detectors

Scintillation detectors

Scintillation detector

Liquid scintillation - coincidence detection

Liquid scintillation vial Contaminant in intimate contact with scintillation medium Swab Pulse of light produced with radiation absorbed Liquid scintillant

Mini 900 series EP15 probe GM gas counter

Mini 900 series E type probe GM gas counter

Mini 900 series 44A probe Solid state scintillation counter

Using the right detector Beta Tritium (Hydrogen-3) Carbon-14 Sulphur-35 Phosphorus-32 Phosphorus-33 18.6 keV 157 keV 167 keV 1.7 MeV 2.5 keV Liquid scint GM tube EP15 GM tube EP15 / Scint 44A Gamma Iodine-125 Cobalt-60 Caesium-137 36 keV 1.17 MeV & 1.33 MeV 662 Scint 44A / GM tube EP15 Scint 44A

Identifying the detector type Look at the label on probe Scintillation probe heavier Scintillation detector higher background rate, switch it on. When in doubt ASK YOUR RPS

Wipe testing Use a swab and wipe surface using tweezers Present to appropriate contamination monitor in low background area For low energy Beta use liquid scintillation counting

Wipe testing low level contamination and low energy Beta. Contamination lifted using absorbent material and counted in a gamma counter or liquid scintillation counter

Radiation spill /incident Don’t Panic !!!

When dealing with spillage of radioactive material Do not to delay medical care unnecessarily Protect yourselves Attend to contaminated persons first Prevent the spillage becoming worse Prevent additional people from becoming contaminated Clear up and decontaminate the area so it can be put into use

Urgent medical care If anyone requires urgent medical care, either by immediate first aid or transfer to A&E DO THIS FIRST . Inform A&E that the casualty is contaminated. Take any obvious steps to reduce or eliminate the hazard to the casualty, to yourselves or anyone attending the casualty. Contact Radiation Protection Service

Protect yourselves Pause, take stock and gather information Don protective clothing If in doubt and there are no casualties involved, GET HELP – but bear in mind that you should always try and ensure the incident is not made worse by your actions

Contaminated persons Washing with soap and water. Always try to localise the contaminated area and just wash that bit. A whole body shower is seldom the best approach. Remove contaminated clothing Washing out any open wound, eyes, mouth, nose etc. If contamination persists contact radiation protection.

Prevent spillage becoming worse Use temporary barriers or close the door. Prevent people walking through the contaminated or potentially contaminated. Use an appropriate contamination monitor to assess the extend of the spill. Check personnel for contamination before they leave the vicinity.

Clear up and decontaminate Purpose is to transfer the radioactive material from the floor or person to the waste store. Use absorbent material i.e. paper towels to soak up the material. Dispose in appropriate bin. Estimate activity. For stubborn areas of contamination use a normal detergent or decon. When clearing up a spill always work from the outside in. Use your contamination monitor!!!

Contamination monitoring Know which is the correct monitor to use. Take care not to contaminate the monitor. Get down close to the contamination. Monitor area systematically. Be thorough .

Other points to note Some one should take charge of the situation. Work as a team not as teams of individuals. Have a plan