IGCSE Physics 5.2.5 Safety Precautions Notes | Nuclear physics 2025

Ionising radiation can have harmful effects on living tissues. It may kill or alter the structure of living cells and cause long-term damage.

It can kill or change the nature of body cells (mutation).
Exposure may cause immediate effects such as tissue burns or sickness.
Long-term exposure can lead to cancer and genetic damage to reproductive cells.

The international radioactive hazard symbol warns people that materials or locations contain dangerous ionising radiation.

Always look for this symbol on containers or lab areas dealing with radioactive materials.

Wear protective clothing such as gloves, aprons, or lead coats.
Keep sources as far away as possible from the body — use tongs or remote tools.
Limit exposure time to the shortest possible duration.
Keep radioactive materials in lead-lined containers clearly labelled with the hazard symbol.

Reduce exposure time — spend minimum possible time near sources.
Increase the distance between source and living tissue.
Use appropriate shielding — e.g., paper for α, aluminium for β, and lead for γ.
Ensure people are informed and move away if a source is unprotected or spilled.

Precaution	Purpose
Wear protective clothing	Prevents direct contact with radioactive material
Use tongs or remote handling	Increases distance and reduces exposure
Minimise exposure time	Reduces absorbed radiation dose
Use lead shielding	Absorbs radiation before it reaches body tissue
Store in lead-lined containers	Ensures radiation does not escape during storage

State that ionising radiation can cause cell damage or mutation leading to cancer.
Describe how exposure is reduced — by time, distance, and shielding.
Remember that radioactive materials must always be labelled with the hazard symbol.
Know which type of shielding stops which radiation (paper → α, aluminium → β, lead → γ).

5.2.5 Safety Precautions