Session 5

Question 1

What are Physical Agents?

Answer 1

Physical hazards caused by the interaction between energy and matter

Question 2

Energy Types

Answer 2

○ Sound waves
		○ Radiation
		○ Light energy
		○ Thermal energy 
Electrical energy

Question 3

Release of Physical Energ

Answer 3

○ Sudden or uncontrolled like an explosive load noise

Sustained like long exposures to lower noise levels

Question 4

• Main types of Physical Agents

Answer 4

○ Noise 
		○ Vibration 
		○ Ionizing and non-ionizing
		○ Radiation 
		○ Pressure
Temperature

Question 5

What is Sound?

Answer 5

• Defined as any pressure variation that the ear can detect
• A wave motion is triggered when an element sets the nearest particle in motion. It then gradually spreads further away from the source
• Key Concepts: frequency and amplitude
○ Amplitude
§ The SIZE of vibration
§ The bigger the amplitude, the louder the sound
§ No change of pitch in increasing the pitch, it only makes the vibrations bigger
Sound has a pitch and frequency and it defines as the number of sound waves per second

Question 6

Noise

Answer 6

• Noise is “unwanted sound”

Question 7

Type of Noise

Answer 7

○ Continuous
○ Intermittent
Impulsive