background radiation and contamination

three examples of where background radiation comes from

1. radioactivity of naturally occurring isotopes: in air, in food, in building materials and in the rocks

2. radiation from space (cosmic rays) mostly comes from the sun but earth’s atmosphere protects us

3. radiation due to human activity e.g. nuclear waste, only a tiny proportion of total background radiation

what is irradiation and how can it be reduced

exposure to radiation,

irradiation does not make it radioactive

reduced by keeping sourced in lead lines boxes, standing behind barriers of a different room and using remote controlled arms

what is contamination

unwanted radioactive atoms getting onto or into an object

why can contamination cause you harm and what can you do to reduce it

contaminating atoms might decay releasing radiation, radioactive particles could get inside your body causing harm

reduced by:

• gloves and tongs when handing sources to avoid particles getting stuck to your skin.

• industrial workers wear protective suits to stop them breathing it in

outside the body, what type of radiation is the most dangerous

beta and gamma, because they can penetrate body and get to delicate organs

alpha cant penetrate the skin

inside the body, which radiation in the most dangerous

alpha because they do damage in a localised area. contamination instead of irradiation is the major concern when working with alpha sources.

beta sources are less damaging and radiation is absorbed over a wider area and some passes out the body altogether

gamma is the least damaging as they mostly pass straight out and the least ionising power