7 - 23 Radiation and half-life
Detectors of ionizing radiation
● ***Becquerel (Bq): measure of how many unstable nuclei disintegrating (breaking
up)
● Photographic film (film badges)
○ Goes from transparent to darker when absorbs radiation
○ Worn by people working with radiation, checked regularly to monitor levels
of radiation absorbed
○ Open window (labelled 1-6) allows all types of radiation through, ∴
showing exposure to beta and gamma radiations
■ Windows 2-3 have plastic of different thicknesses, allowing people to
examine & tell what kinds of beta radiation they have been exposed
to
■ Windows 4-6 are of different metals (e.g.: lead, tin) allowing detection
of gamma rays (& other ionizing radiations)
1
Detectors of ionizing radiation
● ***Becquerel (Bq): measure of how many unstable nuclei disintegrating (breaking
up)
● Photographic film (film badges)
○ Goes from transparent to darker when absorbs radiation
○ Worn by people working with radiation, checked regularly to monitor levels
of radiation absorbed
○ Open window (labelled 1-6) allows all types of radiation through, ∴
showing exposure to beta and gamma radiations
■ Windows 2-3 have plastic of different thicknesses, allowing people to
examine & tell what kinds of beta radiation they have been exposed
to
■ Windows 4-6 are of different metals (e.g.: lead, tin) allowing detection
of gamma rays (& other ionizing radiations)
1
