BLOCK 5: PHYSICAL/BIOLOGICAL HAZARDS AND CONTROLS - Unit 1: Intro to Noise (complete)

Question 1

The USAF ____________________________ Program (HCP) is designed to protect workers from the harmful effects of hazardous noise.

Answer 1

Hearing Conservation Program (HCP)

It is BE’s job to evaluate work areas for sources of hazardous noise as well as to determine hazardous noise areas and make recommendations to control exposures.

Question 2

The Air Force regulation that governs the Occupational Noise Program is ____________________.

Answer 2

Air Force Instruction (AFI) 48-127, Occupational Noise and Hearing Conservation Program

It covers responsibilities, hazardous noise surveillance requirements, personnel and equipment standards, hearing protection, hazardous noise controls, and fitness and risk evaluations.

Question 3

____________________ is the OSHA regulation governing the Occupational Noise Program.

Answer 3

29 Code of Federal Regulations (CFR) 1910.95 - Occupational Noise Exposure

Question 4

TRUE OR FALSE

One of Bioenvironmental Engineering’s responsibilities is approving of hearing protection devices (HPD).

Answer 4

TRUE

Question 5

THE AEROSPACE MEDICINE SQUADRON/AIR RESERVE COMPONENT (ARC) MEDICAL UNIT COMMANDER is the _______________ for the occupational health program.

Answer 5

MANAGER

Question 6

TRUE OR FALSE

One of Bioenvironmental Engineering’s responsibilities is to perform fitness and risk evaluations by conducting the job safety analysis.

Answer 6

FALSE

This is the responsibility of the Installation and/or Organizational Safety Staff, along with reporting HCP noncompliance, and identifying noting new hazards in periodic safety inspections to BE.

Question 7

What is the primary responsibility of Squadron Commanders in regard to the HCP?

Answer 7

Ensure the workplace and workplace supervisors comply with all OSHA, DOD, and AF HCP requirements.

Question 8

TRUE OR FALSE

Workplace Supervisors have a responsibility to provide a copy of 29 CFR 1910.95 in the workplace so it is available to employees.

Answer 8

TRUE

This is in effort to ensure compliance and availability of HPDs for workers exposed to hazardous noise.

Question 9

WHICH OF THE FOLLOWING IS NOT A RESPONSIBILITY OF PUBLIC HEALTH?

a.) Perform audiometric (hearing) testing
b.) Fit HPDs to personnel exposed to hazardous noise
c.) Maintain accurate rosters of personnel occupationally exposed to hazardous noise and providing updates to medics at least semi-annually or upon request
d.) Track and monitor occupational exam compliance of workers on the HCP

Answer 9

c.) Maintain accurate rosters of personnel occupationally exposed to hazardous noise and providing updates to medics at least semi-annually or upon request.

This is a responsibility of the Workplace Supervisor!

Question 10

Any pressure variation in air, water, or some other medium that the human ear can detect; a longitudinal wave, which is created by vibrating objects that spread through a medium (such as air) from one location to another.

Answer 10

SOUND

During this vibration, the surface of the tuning fork first bends in one direction, and the air molecules next to it become compressed. This causes a slight increase in atmospheric pressure. As the fork moves in the opposite direction, molecules near the fork’s surface are drawn away from the surrounding air to create an area of lower atmospheric pressure. This process is known as rarefaction. The vibrating tuning fork repeats this process over and over, causing alternate areas of compression and rarefaction in the molecules near the fork. These air molecules, in turn, cause compression and rarefaction in the molecules next to them. This forms a repetitive, wave-like motion, known as a sound wave.

Question 11

A reduction of an object’s density; the opposite of compression.

Answer 11

RAREFACTION

Question 12

Any unwanted sound.

Answer 12

NOISE

Question 13

The speed of sound.

Answer 13

VELOCITY

The velocity of a sound wave varies depending on the temperature and density of the material through which the sound travels. The higher the temperature is, the faster the velocity.

Question 14

Velocity increases as a material’s density _______________, because denser materials have molecules that are closer together.

Answer 14

INCREASES

This allows a more rapid transfer of energy as the wave travels through the material. As a result, sound always travels much faster in water or solids than in air.

Denser Material = Faster Velocity

Question 15

The speed (velocity) of a sound wave is always equal to the _______________ of the wavelength and the frequency.

a.) sum
b.) difference
c.) product
d.) quotient

Answer 15

PRODUCT

Velocity = wavelength x frequency

Question 16

The distance from one point of a sound wave to the same point on the next wave.

Answer 16

WAVELENGTH

Question 17

One complete compression and rarefaction.

Answer 17

CYCLE

The wavelength is the distance a sound wave travels in a single cycle.

Question 18

How often a sound wave will repeat in a second. It is measured in cycles per second, also known as hertz (Hz).

Answer 18

FREQUENCY

Question 19

Frequency is perceived as pitch. Most people are able to hear sounds with frequencies ranging from ____________________ Hz, commonly referred to as the normal human range of hearing.

Answer 19

20 - 20,000 Hz

Question 20

A sound wave that can be characterized by one single frequency is known as a _______________

Answer 20

PURE TONE

In our daily lives, we seldom hear these pure tones.

Question 21

A wide variety of different tones and amplitudes mixed together so that no single one is recognizable; a combination of many tones or frequencies.

Answer 21

COMPLEX SOUND

As seen in here, there are a large number of different size sharp peaks in a seemingly random pattern.

Question 22

A range (or band) of frequencies extending from one frequency to exactly double that frequency. In other words, the upper frequency is twice the lower frequency.

Answer 22

OCTAVE BAND

Question 23

The frequency in the center of an octave band.

Answer 23

CENTER FREQUENCY

Question 24

Identify the unit of measurement for

Velocity (c)

Answer 24

FEET PER SECOND (FT/SEC)

Question 25

Identify the unit of measurement for

Wavelength (λ)

Answer 25

FEET PER CYCLE

Question 26

Identify the unit of measurement for

Frequency (f)

Answer 26

CYCLES PER SECOND (CPS) or HERTZ (Hz)

Question 27

The total amount of sound that a source produces; the “strength” of a sound source.

Answer 27

SOUND POWER / ACOUSTICAL POWER

Question 28

Sound power is measured in __________

Answer 28

WATTS (W)

Question 29

The amount (portion) of sound power per unit area that comes to a particular receiver.

Answer 29

SOUND INTENSITY

Question 30

Identify the unit of measurement for

Sound Intensity

Answer 30

WATTS PER SQUARE METER (W/M²)

Question 31

The difference between normal atmospheric pressure and the actual pressure during compression and rarefaction.

Answer 31

SOUND PRESSURE

It is not related to wavelength or frequency. A sound with a frequency of 1000 Hz, for example, may have very small pressure and be heard as a soft tone, or it could have a high pressure and sound loud.

Question 32

Sound Pressure is measured in _______________ or _______________

Answer 32

NEWTONS PER SQUARE METER (N/M²) or PASCALS (Pa)

Question 33

Sound pressure __________ is what noise measurement instruments display in decibels (dB).

Answer 33

LEVEL

Question 34

“unit of measurement of sound level.” (The Noise Manual, Appendix I:
Definitions). The unit that describes sound pressure level at a specified distance.

Answer 34

DECIBEL (dB)

Question 35

The process by which sound instruments are calibrated to respond to frequencies in the same way as the human ear so they are all perceived to have the same loudness when they have the same number of weighted decibels.

Answer 35

DECIBEL WEIGHTING

Question 36

When no weighting is used, the instrument response is said to be “_______” (as on a graph), and 0 dB corresponds to 0.00002 N/m2 at all frequencies.

Answer 36

FLAT

Question 37

ANATOMY OF THE EAR

Answer 37

AURICLE

Question 38

ANATOMY OF THE EAR

Answer 38

COCHLEAR AND VESTIBULAR BRANCHES OF AUDITORY NERVE

Question 39

ANATOMY OF THE EAR

Answer 39

TYMPANIC MEMBRANE (EARDRUM)

Question 40

ANATOMY OF THE EAR

Answer 40

EXTERNAL AUDITORY CANAL

Question 41

ANATOMY OF THE EAR

Answer 41

ROUND WINDOW

Question 42

ANATOMY OF THE EAR

Answer 42

STAPES AND FOOTPLATE

Question 43

ANATOMY OF THE EAR

Answer 43

MALLEUS

Question 44

ANATOMY OF THE EAR

Answer 44

EUSTACHIAN TUBE

Question 45

ANATOMY OF THE EAR

Answer 45

COCHLEA

Question 46

ANATOMY OF THE EAR

Answer 46

OVAL WINDOW

Question 47

ANATOMY OF THE EAR

Answer 47

FACIAL NERVE

Question 48

ANATOMY OF THE EAR

Answer 48

SEMICIRCULAR CANALS

Question 49

ANATOMY OF THE EAR

Answer 49

INCUS

Question 50

Effects of excessive noise exposure on the ear to include noise-induced hearing loss, tinnitus, and acoustic trauma.

Answer 50

AUDITORY EFFECTS

Question 51

The result of damage to the hair cells and accompanying degeneration of the nerve fibers in the ear.

Answer 51

SENSORINEURAL HEARING LOSS (noise induced)

Question 52

The condition in which people perceive they hear sounds (ringing, roaring, whistling, humming, hissing, etc.) in one or both ears when there is no actual sound around them.

Answer 52

TINNITUS

Sometimes this can be caused by a blow to the head or certain medications, but the predominant cause is long term exposure to hazardous noise. Though this is often temporary, there are some cases in which tinnitus can become permanent and debilitating.

Question 53

“Any pressure variation in air, water, or some other medium, that the human ear can detect.”

Answer 53

SOUND

Question 54

The temporary or permanent hearing loss due to a sudden, extremely high
intensity noise, such as an explosion.

Answer 54

ACOUSTIC TRAUMA

Question 55

Undesirable effects on the body other than hearing effects caused by high noise levels.

Answer 55

NON-AUDITORY EFFECTS

Question 56

Outline the process by which hearing occurs starting with soundwaves arriving at the outer ear and ending with neural processing.

Answer 56

Sounds enter the outer ear via the external auditory canal and strike the tympanic membrane (eardrum) causing it to vibrate. This vibration is passed along the three bones of the middle ear. The last of these bones, the stapes, sits in a small niche called the oval window connected to the inner ear. The vibrations of the stapes make the fluid in the inner ear move and stimulate the hair cells and nerve endings in the Organ of Corti (in the cochlea) where the processing actually begins. The stimulated nerves send their signal along the hearing nerve and on to the hearing centers of the brain where further processing and decoding takes place and a person “hears”. (Fundamentals of Industrial Hygiene, 6th ed.)