Biological risks of different types of radiation.

Introduction What is radiation ?

Radiation is the process of emitting energy through a medium or space in the form of waves or particles

Introduction

PARTICLESWAVES

IONISINGNON-IONISING

Ionizing and Non-Ionizing Radiation • Radiation is classified as being either non-

ionizing or ionizing.• Non ionizing radiation is longer

wavelength/lower frequency lower energy. • While ionizing radiation is short

wavelength/high frequency higher energy.(STUDY GUIDE)

Introduction

Introduction

What is Ionizing Radiation?

Type of radiation that has sufficient energy to knock-out electrons in atoms and molecules

electron

Introduction

Types of Ionizing Radiation

Alpha particles Beta particles Gamma rays X-rays Neutrons

Introduction

Introduction

• Types of Non-Ionizing Radiation 1. (extremely low frequency) 2. Radio Frequencies 3. Microwave Frequencies 4. Lasers 5. Infrared 6. Visible Spectrum 7. Ultraviolet This list is in order of lowest to highest frequency .

Introduction

Sources of Radiation

• 1. Natural Sources of Radiation (Radioactive materials)

-Radioactive materials continuously emit radiation. -Cannot be turned OFF. - Radon gas (55%)• is the second leading cause of lung cancer in the

United States after smoking.

Introduction

• Sources

2. Radiation emitting devices or equipment (e.g. X-ray machines) -Machines can be turned ON and OFF • When turned OFF, no radiation is emitted. 3. Man-made sources. -Nuclear reactors -Medicine (Modern Health Care) -Food & agriculture -Industry -Nuclear weapons

Introduction

• What could happen to the body when exposed to radiation?

• -Biological effects on living cells 1. Cells experience DNA damage that are detected & repaired.

2. DNA damage not repaired and causes cell death.

3. Cell experiences DNA mutation and may induce cancer.

Introduction