The International Society for Respiratory Protection (ISRP) is a non-profit organisation that provides education and information about respiratory protection. The primary purpose of ISRP is to bring together occupational health and safety professionals in the field of respiratory protection. Members are encouraged to share their opinions and disclose their research findings.
The European section of the ISRP is holding a webinar on radiological hazards on 9th December at 2 pm UK time or 9 am EST. The webinar will last approximately two hours and include the following key-note presentations:
- Chris Jones, Head of Corporate RPA, on behalf of the Atomic Weapons Establishment will present on the Basics of Radiological Hazards
- Peter Hillier, Technical Authority (Characterisation) at the National Nuclear Laboratories, will present the following case study: Radiological RPE Requirements in Nuclear Decommissioning (Particulate Hazards).
- Paul Cooper, Operational lead CBRN Support at the Atomic Weapons Establishment (CBRN-UK Exec Committee), will present the following case study: Radiological RPE Requirements in Operational Use (Gaseous / Vapour Hazards).
If you have any further questions, please contact the ISRP European Section Chair, Dave Crouch (dcrouch@mmm.com).
Ionising radiation
Ionising radiation is an invisible, odourless, and tasteless form of energy emitted by a radioactive source. We are constantly exposed to radiation as it is naturally occurring, even in our food and water. However, other radiation sources are man-made—from radioactive materials used in diagnostic imaging to industrial radiography to dirty bombs.
Ionising radiation is comprised of four naturally occurring parts: alpha particles, beta particles, gamma rays, and neutrons, which are all formed as radioactive materials decay.
Alpha particles, such as those in polonium 210, lose momentum rapidly, so they travel only very short distances in the air (a few cm) and do not penetrate further than the outer layers of human skin. They are hazardous only when inhaled, ingested, injected, or absorbed (through a wound) where they come into contact with inner body tissue.
Beta particles travel further and can penetrate further. They can penetrate through skin and clothing, although all levels of PPE provide protection, and safety glasses should be worn to protect the eyes. Beta particles can cause radiation skin injury. Moreover, when inhaled, ingested, injected, or absorbed, they are hazardous to internal organs.
Gamma rays are uncharged photons of electromagnetic radiation and can travel many metres through the air, quickly penetrating the human body. However, it is possible to shield from gamma rays using a dense material such as concrete or lead.
Neutrons are uncharged particles. They can travel long distances and penetrate everything with the exception of thick layers of concrete and water. Fortunately, these hazardous particles are only likely to be emitted during the initial stages of a nuclear detonation or accident or in very particular industrial applications.
Exposure to ionising radiation due to an emergency
A person is considered to be exposed when either the whole body or part of the body is irradiated. They can either be contaminated externally when radioactive material is deposited on the skin or clothes or internally through inhalation, ingestion, or absorption. There are three key elements that have an effect on the contamination level resulting from exposure:
Duration: Halving exposure time halves the radiation dose. If emergency responders receive functional training and are familiar with the devices they use in the field, the time they spend exposed to radioactive sources can be reduced.
Distance: Due to inverse square law, increasing a person’s distance from the source reduces the dose they receive. Using radiation detection equipment to discover the location of the source is paramount to ensure emergency responders maintain a safe distance from it.
Shielding: The material used to shield from the radiation has a significant effect as it absorbs the energy of the radiation. Different thicknesses of concrete and lead are used for either primary or secondary radiation.
How is radiation contamination treated?
If an individual is contaminated by radiation, they will be irradiated until the radioactive is removed. External contamination with dust or particulate matter is usually addressed with wet decontamination.
However, if an individual is contaminated internally, the treatment procedure is more complex. Medical personnel need to ascertain the absorbed radiation dose. As such, they must gather detailed information to give the contaminated individual the best treatment and chance of survival. The information needed includes the following:
Type of radiation: Identifying the type of radiation exposure will guide the treatment of people with radiation sickness.
Known exposure: Distance from the radioactive source and duration of exposure will inform medical personnel about the potential severity of radiation sickness.
Blood tests: Bone marrow damage is caused by the radiation level absorbed. This can be established by a drop in ease-fighting white blood cells and changes in blood cells’ DNA. Frequent blood tests will be able to provide medical staff vital insights.
Vomiting: Medical staff can establish the absorbed radiation dose by calculating the time between radiation exposure and when the patient begins to vomit. Higher doses lead to quicker vomiting.
Dosimeter: If this device was exposed to the same radiation event as the affected person, it measures the dose of radiation they absorbed.
Survey meter: Using a survey meter to survey the affected person can determine where on the body the radioactive particles are located.
What injuries are caused by exposure to radiation?
Exposure to ionising radiation can kill cells and cause tissue and organ damage, known as deterministic injury. A person is likely to have suffered from deterministic injury when they have suffered one, or a combination, of the following:
- A newly diagnosed acute bone marrow depression
- Burns with no recent exposure to heat
- Sudden hair loss
Exposure also leads to a long-term risk of developing cancer caused by damage to genetic material as well as hereditary effects, known as stochastic risk. The increase in a person being diagnosed with cancer is approximately 5% per sievert (the unit used to measure ionising radiation dose) effective dose of radiation above the expected risk.
What is the best preparation for radiological hazards?
While controlled exposure to ionising radiation is safe if measures are taken, contamination from an accident or explosive device is highly harmful to human health. Minimising the exposure duration, increasing the distance, and seeking shelter are the three most important precautions that can be taken to minimise harm to health.
Emergency first responders are reliant on devices such as survey meters and dosimeters to detect radioactive sources and implement safety measures. The better training they have, the easier it will be to implement precautions and protect human health. Simulation training provides instructors with realistic methods of designing training exercises.
Simulation equipment such as Argon Electronics’ Radsim GS4 Simulator, a simulation source; the RadEye GF-10 Simulator or the AccuRad PRD Simulator, survey simulators; and the UDR-13 or UDR-14 SIM, dosimeters; will enable emergency first responders to train with simulators that are near-exact replicas of the original devices.
Over thirty years, Argon Electronics has developed very close relationships with original device manufacturers. Our simulators provide emergency responders with a deep understanding of how to use the devices whilst not being exposed to radioactive sources.
Getting in touch with Argon Electronics
If you require any additional information about integrating simulation-based technologies into a training programme, please feel free to contact us. We would be delighted to advise you and provide you with a demonstration of how our systems work.
