Dangers of EM Waves

This lesson covers the hazards associated with different parts of the electromagnetic spectrum, the difference between ionising and non-ionising radiation, and the safety precautions used to reduce risk, as required by the Edexcel GCSE Combined Science specification (1SC0).

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Ionising vs Non-Ionising Radiation

EM waves can be classified as ionising or non-ionising based on their energy and their ability to remove electrons from atoms (ionisation).

Category	EM Waves	Energy	Effect on Atoms
Non-ionising	Radio waves, microwaves, infrared, visible light	Lower	Cannot remove electrons from atoms; mainly cause heating
Ionising	Ultraviolet (higher energy UV), X-rays, gamma rays	Higher	Can remove electrons from atoms; can damage DNA and cause mutations

What Is Ionisation?

Ionisation is the process where radiation has enough energy to knock an electron out of an atom, turning it into an ion. This can:

• Damage or destroy cells.
• Cause mutations in DNA.
• Lead to cancer if the mutations affect cell division.