Chapter 2- Flashcards
ALARA stands for what ?
As Low As Reasonably Achievable- based on the assumption that any exposure to ionizing radiation carries with it some risk
AEGL or ‘eagles’ refer to what?
AEGL or ‘eagles’ are intended to provide uniform exposure guidelines public for a single short -term exposure.
Local effect vs. Systemic effect
Local effect implies an effect at a single point of contact ( ie a burn) where systemic effect is when a compound enters the body and has an effect on organs or systems in the body
The ‘Health Hazard equation’ can be expressed as what ?
Health Hazard = Exposure + Toxicity
Hepatoxins attack what organ of the body ?
Liver
Dose is a measure of what two factors
Dose = concentration x time
LD50 is a measurement of relative toxicity, it is in reference to what?
Lethal dose 50- the dose at which 50% of the exposed population dies. Often refers to substances which are injected, adsorbed, or ingested. It is relative to body weight of the subject. It is expressed in mg of substance/Kg of bodyweight.
LC50 is a measurement of relative toxicity in reference to what?
Lethal concentration 50- the concentration at which 50% of the exposed population dies. Often refers to substances which are inhaled. It is relative to body weight of the subject. It is expressed in micrograms of substance/Kg of bodyweight for mists or dusts. or in PPM for gasses.
Ionizing Radiation is a hazard, why?
Ionizing radiation is characterized by its ability to create charged particles, or ions in anything it strikes. Exposure to low levels of ionizing radiation can produce short or long term cellular changes with possibly harmful effects. X ryas are a form of ionizing radiation
Alpha particles can penetrate how far?
3-4 inches in air and can be stopped by a sheet of paper or human skin. Primarily a hazard when inhaled or ingested.
Beta Particles are how big?
Roughly the same size as an electron. Can penetrate as fas as a few yards from source and pass through skin and or clothing, however are unable to penetrate internal organs. Can be shielded by glass, plastic, or foil
Why are Gamma rays so dangerous to the Hazmat responder ?
Due to the speed at which they move gamma rays are the most dangerous. gamma rays are able to pass though many layers of protection and is difficult to shield.
How is time important when dealing with Radioactives?
The shorter the exposure time the less the exposure.
Distance is important to the Hazmat repsonder with regaurd to radioactive compounds why?
The closer the body to the source the greater the exposure. The inverse square law can be used for safety measures. If the distance from the source is doubled, the energy received is reduced by a fourth.
Shielding is an important tool for Hazmats because of ..?
Not all forms of radiation can be stopped with our PPE. ( only Alpha particles) so heavier materials must be used to protect humans from radiation sources. Lead and water are often used in industry, however are often impractical for responders. Any shielding is better than none.
