Presentation on theme: "Radiation Protection. Internal/External Hazard Internal hazardInternal hazard arises through ingestion or inhalation of a radiation material – not a problem."— Presentation transcript:
Internal/External Hazard Internal hazardInternal hazard arises through ingestion or inhalation of a radiation material – not a problem in radiology.
Internal/External Hazard External hazardsExternal hazards Arise from exposure to external sources. X-ray sets, emissions from sources etc
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 mSv to 1 Sv
Other Monitoring Extremity –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
Liquid scintillation - coincidence detection
Liquid scintillation vial Contaminant in intimate contact with scintillation medium Pulse of light produced with radiation absorbed Swab 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
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 Dont 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 1.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