Background Radiation And Contamination Flashcards
what is background radiation
the low level radiation that is around us all the time
what are the three ways that background radiation has established itself on earth
- radiation of naturally occurring unstable isotopes which are around us
- radiation from space
- radiation due to human activity
what are some examples of where naturally occurring radiation can come from
- unstable isotopes in the air
- or is some foods
- or building materials
- or rocks
what is radiation from space known as
cosmic rays
where do most of the cosmic rays we experience come from
- the sun
- the earths atmosphere protects us from alot of the radiation
what are examples of radiation due to human activity and to what extent does it impact the total background radiation
- fallout from nuclear explosions or nuclear waste
- they only represent a tiny proportion of the total background radiation
what can the amount of radiation youre exposed to alternatively be called
the amount of energy your body absorbs
what is the amount of radiation youre exposed to technically called
absorbed radiation dose
what two factors can cause how much radiation youre exposed to to vary
- where you live
- if you have a job that involves radiation
what happens to an object near a radioactive source
they are irradiated by it
what is irraidiation
- when youre exposed to it (the radiation in this case)
- we are always being irradiated by background radiation sources
does irradiating something make it radioactive
no
what can you do to reduce the effects of irradiation
- keeping things in lead-lined boxes
- standing behind barriers
- being in a different room and using remote controlled arms
why do medical staff who work with radiation wear photographic film badges
to monitor their exposure to radiation
when does an object become contaminated by radiation and what is an example of this
- when unwanted radioactive atoms get onto an object
- if you touch a radioactive source without wearing gloves your hands will be contaminated
why is radioactive contamination dangerous
- the contaminating atoms could then decay
- releasing radiation which can cause you harm
- especially when radioactive particles get inside your body
when does a contaminated person stop being at a risk of harm
- when the contamination is removed
- or all the radioactive atoms have decayed
what should be used when handling radioactive sources and why
- gloves an tongs
- to avoid particles getting stuck to your skin or under your nails
- some industrial workers wear protective suits to stop them from breathing in particles
when does radiation lead to tissue damage
when it enters living cells and ionises atoms and molecules within them
what do lower doses of radiation cause in the body
- minor damage without killing the cells
- this can give rise to mutant cells which divide uncontrollably
- this is cancer
what do higher doses of radiation cause in the body
- they tend to kill cells completely
- causing radiation sickness if a lot of cells all get blatted at once
- this can lead to vomiting, tiredness or hair loss
when are beta and gamma radiation the most dangerous compared to alpha and why
- when they are outside the body
- because they can penetrate the body and get into delicate organs
- alpha is less dangerous because it cant penetrate the skin
when are alpha particles the most dangerous and why
- when they are inside the body
- because they are strongly ionising
- so they do damage on a very localised area
- that means contamination rather than irradiation is the major concern when working with alpha particles
