Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Industrial Hygiene > Noise > Flashcards

Noise Flashcards

1
Q

What is the purpose of the Eustachian tube?

A

releases pressure inside the ear by draining fluid into the throat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Describe the outer ear

A

outside of ear to the eardrum, channels and directs sound to the ear drum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the visible part of the ear and what is its purpose?

A

pinna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

what is the purpose of the middle ear?

A

transfers sounds into electrical impulses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is another name for the eardrum?

A

tympanic membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the purpose of the bone in the ear?

A

Bone transmits vibrations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are some conditions that can impact the pinna?

A

Sunburn, frostbite, cauliflower ear

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are conditions of the ear canal?

A

packed wax, foreign objects, otitis (infection of the ear canal)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are conditions of the ear drum?

A

Perforation or rupture (diving, blows, explosions)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are conditions of the eustachian tube?

A

swelling, obstruction (allergy or infection)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are conditions of the middle ear?

A

Bacterial infection, fixation of bones (bone disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What can cause damage to the chochlea?

A

infection, toxins, excessive vibrations, heavy metals, organic solvents, CO, noise induced hearing loss, age induced hearing loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are conditions related to the vestibular system?

A

labyrinthitis (vertigo, nausea, vomit), tumors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is occupational hearing loss?

A

hearing impairment in one or both sides from one’s employment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is acoustic trauma?

A

Injury to inner ear produced by one or few exposures to sudden intense acoustic forms of energy (explosions or blasts)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is noise induced hearing loss?

A

Cumulative permanent loss of hearing developed over months or years of exposure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What factors determine duration and severity of hearing loss?

A

1) Sound level
2) Frequency of sound
3) Duration of sound - longer duration worse
4) Temporal distribution
5) Type of sound energy
6) Individual genetic and age factors
7) concurrent exposure to ototoxic compounds

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What sound levels will make hearing loss more severe?

A

sound levels >60-80 dB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What frequency will make hearing loss more severe?

A

500- 200 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Give examples of types of sound energy

A

Continuous vs. intermittent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is sound?

A

any pressure variation that the human ear can detect. it produces a sensory response in the nerves

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is noise?

A

Sound that bears no information, often unpleasant and likely harmful

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are sound waves?

A

Vertical, vibrating plate causing small, repeated fluctuations in atmospheric pressure which propagate to the eardrum causing it to vibrate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Describe the frequency of sound (f)

A

number of times per second that an air molecule is displaced from its position of equilibrium, rebounds in opposite direction and returns to equilibrium

Horizontal distance between peaks

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How is frequency measured?

A

Hertz (Hz)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

How is frequency perceived?

A

pitch (high frequency noise is more annoying)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Draw the physics of sound

A

see slide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What would be the frequency of a soundwave with 2 cycles in 1 second?

A

2 Hz

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is amplitude?

A

loudness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What is frequency?

A

pitch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is wavelength?

A

distance between two analogous points on two successive parts of wave- Distance a sound wave travels in one cycle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the velocity of sound?

A

speed of sound

always equal to product of wavelength and frquency

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the equation for velocity?

A

c=f(wavelength)

velocity = frequency * wavelength

see slide to wavelength symbol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is sound pressure?

A

Variations in atmospheric pressure that are detected by eardrum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

How is sound pressure measured?

A

micropascals
N/m2
microbars
dynes / cm2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What are the common conversions for sound pressure?

A

1Pa = 1 N/ m2 = 10ubar = 10d/cm2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What is the decibel?

A

unit of sound - minimum perceptible difference i loudness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

How does a decibel relate to a bel?

A

1/10 of a bel

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What is intensity?

A

sound power, measure in W/m2

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What happens to intensity as you move away from the source?

A

Diminishes with distance

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What is a problem with intensity?

A

hard to measure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What tool measures sound pressure?

A

Sound level meters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is the symbol for sound pressure level?

A

Lp

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is the unit for sound level pressure?

A

dB

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What type of agent is noise?

A

Physical agent

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What is the major concern with noise?

A

It can cause permanent hearing loss (permanent threshold shift)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

What threshold shift can occur after one loud incident or minor blast?

A

temporary threshold shift

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

Hearing loss factors

A
  • sound pressure level
  • frequency of sound
  • duration of exposure
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What are the types of hearing loss?

A 
Conduction
Sensorineural
Temporary vs. permanent threshold shift
Tinitus
trauma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

Describe conductive hearing loss

A
  • blockage, damage to eardrum

- not due to noise in most cases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

Describe sensorneural hearing loss

A
  • damage to inner ear or nerve

- chronic noise exposure does this

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

What is damaged by noise?

A

Hair cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What are some of the problems with noise?

A

1) Distraction of workers –> accidents
2) Interference with communication –> accidents
3) Annoyance–> stress or violence

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

When is a hearing conservation program required?

A

> 85 dB over 8 hours

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is the goal of the hearing conservation program?

A

to prevent hearing impairment as a result of noise exposure on the job

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What are the 5 components of the hearing conservation program?

A

1) exposure monitoring
2) audiometric testing
3) hearing protection
4) employee training
5) record keeping

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What is the rationale for HCP?

A
  • 20-30 million workers are at risk of irreversible hearing loss due to exposure and noise
  • 9 million other workers are at risk of hearing loss from exposure to ototoxins
  • to save on workers compensation costs
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What are examples of ototoxins?

A

organic solvents, metals, CO

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

Name some elements of the hearing conservation program

A
  • protect and conserve hearing
  • person in charge
  • measure baseline and ongoing exposure
  • control of excessive exposure
  • audiometric testing
  • training
  • SOP
  • Program assessment
  • Records
  • Buy quiet
  • other exposures

Main idea: develop the BEST program, not the required one

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What are environmental risk factors for hearing loss?

A
  • SPL of noise (intensity)
  • Frequency of noise (type of noise)
  • period of exposure (work duration)
  • total work duration
  • surroundings (noise reflected or absorbed)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is the most important environmental risk factor?

A

Surroundings

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What are host factors that impact hearing loss?

A
  • distance of work situation from noise source
  • position of worker’s ear due to work station
  • years of employment
  • individual susceptibility
  • age
  • co-existing loss or disease
  • exposure outside of work
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

What are the most important host risk factors for hearing loss?

A

1) Age

2) Coexisting loss or disease

64
Q

What equipment can be used to measure noise?

A
  • sound level meters
  • octave band analyzers
  • noise dosimeters
65
Q

What are the differences between sound level meters, octave band analyzers, and noise dosimeters?

A

Sound level meters: area- measure sound pressure variation in the air

Octave Band Analyzers: Area, brake noise down in frequency components for complex situations

Noise Dosimeter: Personal measurement- exposure monitors logging noise energy

66
Q

What are the components of the meter?

A
  • Microphone
  • Amplifier
  • Weighting Scale
  • Output
67
Q

What is the role of the microphone in a sound level meter?

A

Responds to sound pressure variations and produces and electrical signal

68
Q

What is the role of the amplifier in the sound level meter?

A

Increases the output signal

69
Q

What is the purpose of the weighting scale in the sound level meter?

A

electronically adjusts the amplification of frequencies giving some more amplification than others

70
Q

What are the different weighting scales?

A

Flat, A, B, C scales

71
Q

What is the most common weighting scale for sampling and why?

A

A, because OSHA standards are in the A scale (dBa)

72
Q

What is the purpose of the output in sound level meters?

A

Digital display that shows dB

73
Q

What can time weightings be set to?

A

fast, slow, or impulse

74
Q

What determines how you set your time weighting?

A

how quickly you want the meter to respond to changes in sound

75
Q

What can noise dosimeters determine?

A
  • % of allowable exposure
  • instantaneous current SPL
  • Peak sound SPL
  • Time History ** of exposure
  • SPL average
  • TWA*** sound pressure level
76
Q

Name some work processes that would create noise levels above 85 dB

A
  • Hand drill
  • Chain Saw
  • Belt Sander
  • Table Saw
77
Q

What is the threshold or threshold gate?

A

-lower limit of what SPL will be included

78
Q

What is the criterion level?

A

OSHA standard of 90dBA, used to determine % of allowable exposure, it is the & of the criterion

79
Q

Who is it important to interview for their ideas?

A

workers

80
Q

What observations should be made while noise sampling?

A
  • position relative to sources
  • exposure and time
  • obvious worker hearing problems
  • noise source information
  • surface materials
  • controls & feasibility
81
Q

Considerations for noise sampling

A
  • diagrams
  • locations of sampling/ workers
  • data sheets
  • checklist (NIOSH)
  • Observations
82
Q

What is the exchange rate?

A

Sound pressure increase or decrease that determines a halving or doubling of exposure time

83
Q

What is another name for exchange rate?

A

doubling rate

84
Q

What is the OSHA exchange rate?

A

5 dBA

85
Q

What is the NIOSH exchange rate?

A

3dBA

86
Q

Who follows the NIOSH exchange rate?

A

EPA, EU- 3dBA

87
Q

Which exchange rate is based on physics?

A

NIOSH- 3 dBA

88
Q

What is the DOD exchange rate?

A

4 dBA

89
Q

What is sound power

A

total sound energy emitted by a source er unit time

90
Q

Lw=10logW/Wo

What is W? Units?

A

Sound power (watts)

91
Q

Lw=10logW/Wo

What is Wo? Units?

A

reference power (10^-12 Watts)

92
Q

Lw=10logW/Wo

What is Lw?

A

Sound power level (dB)

93
Q

What is the short method for adding decibels?

A

Use the table

94
Q

0-1 dB difference =

A

+ 3 dB

95
Q

2-3 dB difference =

A

+2 dB

96
Q

4-9 dB difference =

A

+1 dB

97
Q

10 dB or more difference

A

+0 dB

98
Q

What is the equation for the TWA for noise?

A

Dose % = 100 [(C1/T1)+(C2/T2)+…]

99
Q

Dose % = 100 [(C1/T1)+(C2/T2)+…]

What is the units for dose?

A

%- not units

100
Q

Dose % = 100 [(C1/T1)+(C2/T2)+…]

What are the Cs?

A

individual exposure time (hours) at specific sound pressure levels

101
Q

Dose % = 100 [(C1/T1)+(C2/T2)+…]

What are the Ts?

A

Allowable exposure time (hours) at specific sound pressure levels- find on OSHA site (or use NIOSH table based on exchange rate of 3dB)

102
Q

Is TWA for sound the same as TWA for airborne agents?

A

NO

103
Q

What is the alternative to expressing dose as a percentage?

A

express as a decimal

104
Q

How does dose in decimal form compare to exposure standards?

A

> 1- overexposed above either the PEL or REL

>.05- above the action limit for OSHA (if using OSHA exchange rate)

105
Q

If dose is expressed in %, what is the percent for over exposure? and percent for action limit?

A

> 100% & >50%

106
Q

How long can someone stay in an area of a given SPL- equation

A

tallowed = T/ [2(Lp-Lcrit)/x]

107
Q

tallowed = T/ [2(Lp-Lcrit)/x]

What is tallowed?

A

allowable exposure time (hours)

108
Q

tallowed = T/ [2(Lp-Lcrit)/x]

What is T?

A

Base period, ususally 8 hours

109
Q

tallowed = T/ [2(Lp-Lcrit)/x]

What is Lp?

A

Sound pressure level dBA

110
Q

tallowed = T/ [2(Lp-Lcrit)/x]

What is Lcrit?

A

Criterion level (dBA)

111
Q

What is x?

A

exchange rate (dBA)

112
Q

When comparing to OSHA standards, what action should be taken if dose >85dBA?

A

baseline measurements & annual audioprograms

PPE required

113
Q

Per OSHA standards, if PEL >90dBA, what actions are needed?

A

Noise control program

  • engineering and administrative controls to reduce exposure to <90 dBA
114
Q

Per OSHA, at what point is PPE required? At what point is PPE no longer adequate?

A

> 85 dBA, >90 dBA

115
Q

What can you do at the source for noise problems?

A
  • Modify
  • Redesign
  • Relocate
116
Q

What can you do at the path level for a noise problem?

A
  • enclosure
  • absorption
  • barrier
117
Q

What can you do on the receiver end to reduce noise exposure?

A
  • enclose
  • absorption
  • relocate
118
Q

What is the cost of controlling noise at the source compared to controlling noise at the path?

A

1/10th the price to control noise at the source

119
Q

What type of agent are the sources?

A

typically mechanical (vibrating or moving surfaces)

120
Q

Why is sound considered to be aerodynaic?

A

unsteady flow of air, specific gas, or stream

121
Q

How do you solve mechanical noise?

A

minimize the change of force (impact)

122
Q

How do you solve aerodynamic issues with noise?

A

Minimize pressure changes/ turbulence

123
Q

What are engineering controls for noise?

A
  • use a quieter machine, process, or materials
  • enclose the source
  • decrease vibration
  • decrease energy
  • decrease driving force
  • change directivity?
124
Q

Name specific engineering controls to control noise problems from mechanical sources

A
  • change the structure/ material of the source
  • lubricate to decrease friction
  • insulate (lagging)
  • dampen the source
  • Brace the source
  • Decrease vibrating area**
  • decrease resonance
  • reduce dropping height
  • decrease rotational speed
  • improve the dynamic balance
  • isolate vibration
125
Q

What must you consider when enclosing the source of mechanical noise?

A

heat build-up

126
Q

Give example of decreasing vibrating area

A
  • using multiple belts instead of 1 thick belt
127
Q

How does damping and bracing work as a control for mechanical noise?

A

makes the source stiffer and reduces vibrations

128
Q

Give an example of insulating the vibration?

A

Add rubber around solid connecting arts

129
Q

How is isolating vibration different than enclosing?

A

enclosing places machinery in room or area, isolating would be like putting up a noise barrier

130
Q

Where there is turbulence, there is…

A

noise

131
Q

What are engineering controls for aerodynamic noise?

A
  • increase absorption of sound
  • decrease reflection
  • decrease reverberation
  • increase distance from source to worker
  • mufflers
  • block the path with baffles
  • enclose the worker
132
Q

What do you need to increase absorption of sound/ decrease reflection, and decrease reverberation?

A

change of materials

133
Q

What is an engineering control at the path level for noise?

A
  • Increasing the distance

- Active noise control

134
Q

By doubling the distance, you decrease SPL by…

A

6dB

135
Q

How does active noise control work?

A

device generates a sound wave opposite or anti-phase of the source sound wave

136
Q

Destructive interference –> ?

A

attenuation

137
Q

What are administrative controls of noise?

A
  • schedule noisy activities when fewest people are present
  • rotate workers between quiet jobs & noisy jobs
  • have very quiet rest areas and lunch areas
138
Q

What are additional strategies to prevent noise exposure?

A

optimize preventative and emergency maintenance

- use specifications to buy quiet

139
Q

What are two types of PPE to prevent noise induced hearing loss

A
  • muffs (around outer ear)

- plugs (in ear canal)

140
Q

How should you select PPE?

A

Select type based on noise and worker

Based on noise reduction rating

141
Q

What NRR should you chose?

A

NRR with highest NRR

142
Q

What NRR difference is meaningless?

A

<3 dB

143
Q

Who gives the NRR for devices?

A

manufacturer

144
Q

How do you determine the noise reduction from the NRR rating?

A

subtract 7, divide by 2, and add to env measurement

145
Q

What are the limitations of NRRs?

A

Measure based on optimal conditions and trained workers

146
Q

When do you require plugs & muffs?

A

> 105 dB

147
Q

If there are multiple noise sources and noise is above 105 dB

A

take higher NRR and add 5 dB

148
Q

What is the name for medical monitoring for hearing?

A

audiometry

149
Q

What audiometry measurements do you need to take?

A
  • pre-placement
  • baseline
  • annual
150
Q

What does audiometry determine?

A

threshold for each ear and different frequencies

151
Q

What is the requirement before the test?

A

Should be in quiet area 14 hours before test

152
Q

What is the instrument for audiometry?

A

audiometer

153
Q

Where is audiometry measured?

A

audiometric booth

154
Q

What are the prescribed frequencies for audiometry testing?

A
  • 500
  • 1000
  • 2000
  • 4000
  • 8000 Hz
155
Q

What audiometry devide givs data?

A

audiogram

156
Q

What considerations must be taken when analyzing results from audiometry?

A
  • adjust for age

- compare to past thresholds

157
Q

What is the standard threshold shift?

A

if average of losses at each frequency is greater than or equal to 10 dB

Industrial Hygiene (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions