Noise, Vibrations and Avitatio Protective Equipment

Question 1

What is sound?

Answer 1

Mechanical radiant energy that is transmitted by longitudinal pressure waves

Question 2

What are the different types of sound waves?

Answer 2

Longitudinal, mechanical and pressure wave.

Question 3

What is the speed of sound at sea level?

Answer 3

344 m/s

Question 4

What is noise?

Answer 4

Sound that is loud and unpleasant

Question 5

What are the measurable characteristics of noise?

Answer 5

Frequency, intensity and duration.

Question 6

What is frequency?

Answer 6

Cycles per second = Hertz (Hz)

Question 7

What is intensity in regard to noise and vibes?

Answer 7

A measure that correlates sound pressure to loudness

Measure in dB

Question 8

The surgeon general has established ___ decibels as the max level of continuous unprotected exposure to steady-state noise for __ hours.

Answer 8

85 dB and 8 hrs

Question 9

What are the two type of noise?

Answer 9

Steady state and impulse noise

Question 10

What are the types of hearing?

Answer 10

Conductive, sensorineural and mixed

Question 11

What is conductive hearing loss?

Answer 11

Defect or impediment in the external or middle ear
Ex: ear plug, ear infection and ear wax

Question 12

What is sensorial loss?

Answer 12

When the cochlea cilia (small hairs) are damaged

Question 13

What is acoustic trauma?

Answer 13

Sudden and could cause hearing loss.
In excess of 140dB

Question 14

What is a temporary threshold shift?

Answer 14

Single exposure to high level noise
May last for few minutes or hours

Question 15

What is a permanent threshold shift?

Answer 15

Continued for 15hrs, eventually permanent

Question 16

What are the two airframes which flight helmet and CEPs are required for noise protection?

Answer 16

Blackcocks and Chinooks

Question 17

What is vibration?

Answer 17

The motion of an object relative to a reference point (object at rest)

Question 18

What is amplitude?

Answer 18

The maximum displacement from the position at rest

Question 19

What are some sources of vibration in a helicopter?

Answer 19

Transverse flow effect, increased airspeed, hoist ops and turbulence

Question 20

What is Raynaud’s disease?

Answer 20

White finger, prolonged exposure to vibration

Question 21

What are the safety features of aircraft?

Answer 21

Fuselage, landing gear and crash-worthy seats.
Restraint systems and post crash factors

Question 22

What under layer clothing should be worn?

Answer 22

Cotton, Wool and nomex or material approved in 95-1

Question 23

How much heat can NOMEX withstand?

Answer 23

Does not support combustion bust chats at approx 700-800 degrees Fahrenheit