Question 1

Sound and vibration are very similar. Which of the following statements are true?
A) Sound relates to a sensation
B) Vibration is inaudible
C) Vibration is perceived through the sense of touch
D) All of the above

Accepted Answer

Sound and vibration both involve the movement of energy through matter. Sound is the sensation we perceive when our ears detect vibrations in the air, while vibration can be audible or inaudible and is perceived through the sense of touch. Therefore, all three statements are true.

Question 2

Conducting noise surveys involves measuring noise levels at all locations in the workplace.

Accepted Answer

Noise surveys typically focus on areas where noise levels are likely to be high or where workers are exposed to potentially harmful noise, rather than measuring at all locations indiscriminately.

Question 3

The unit of measurement for sound is the decibel, or one-tenth of a bel.

Accepted Answer

This statement is true. The decibel is the standard unit of measurement for sound, which is equal to one-tenth of a bel.

Question 4

Noise control strategies include which of the following?
A) Noise can be reduced at the receiver by enclosing the worker
B) Noise can be reduced along its path by moving the source farther away
C) Noise can be reduced at its source by enclosing the source
D) All of the above

Accepted Answer

All of these strategies are effective in reducing noise levels. Enclosing the worker or the source can help to reduce noise at the source itself. Moving the source farther away can help to reduce noise levels along its path. Different strategies may be more or less effective depending on the specific situation, but all of these options are worth considering when trying to control noise levels.

Question 5

Fit testing is not an important prerequisite for effective noise protection.

Accepted Answer

Fit testing is essential to ensure that hearing protection devices are being worn correctly and are providing adequate protection from noise. Without fit testing, the effectiveness of the hearing protection cannot be guaranteed.

Question 6

Sound is any change in pressure that can be detected by the ear.

Accepted Answer

This is the simple definition of sound, and it is true. Sound is a type of mechanical wave that travels through a medium, which can be detected by the ear or other instruments. The frequency and amplitude of sound waves affect the way they are perceived by the human ear, giving rise to the sensation of pitch and loudness, respectively.

Question 7

Noise is distinguished from sound by which of the following factors?
A) Intensity of noise
B) Unwanted sound
C) Type of noise
D) Duration of exposure

Accepted Answer

Noise refers to unwanted sound. Therefore, option B is the correct answer. The intensity, type, and duration of exposure are all factors that can contribute to the perception of noise, but they do not distinguish noise from sound.

Question 8

What level of DBA is considered the maximum limit of continuous exposure over eight hour days without protection?
A) 150
B) 3
C) 90
D) 20

Accepted Answer

The maximum limit of continuous exposure over eight-hour days without protection is 90 dBA, as per OSHA standards. Option A (150 dBA) is too loud and can cause immediate harm to hearing even with short-term exposure, whereas option B (3 dBA) is too low to cause any significant harm. Option D (20 dBA) is also too low as it falls within the safe range. Therefore, the best choice is C.

Question 9

Impulsive noise reduction involves reducing peak impulse transmission based on the use of PESDs.

Accepted Answer

Impulsive noise reduction typically involves techniques like filtering or error correction, not specifically based on PESDs (Power Electronic Switching Devices).

Question 10

Trying out HPDs to determine how they fit with an individual's anatomical features is known as what?
A) Trial PPE run
B) Fit testing
C) PPE testing
D) PPE run through

Accepted Answer

Fit testing is the process of trying out HPDs to determine how they fit with an individual's anatomical features. The other options are not specific to the process of HPD fitting.

Question 11

Medical professionals have not yet established a procedure for determining if there is a causal relationship between workplace noise and hearing loss.

Accepted Answer

Medical professionals have established procedures for determining if there is a causal relationship between workplace noise and hearing loss, including audiometry testing and exposure assessments.

Question 12

The EPA is replacing its method of using a single number to rate HPDs with a sliding scale showing the low and high range of estimated protection provided.

Accepted Answer

The statement accurately describes the EPA's change in methodology for rating HPDs.

Question 13

Federal regulations require that employees be protected from excessive noise in the workplace.

Accepted Answer

OSHA (Occupational Safety and Health Administration) regulations require employers to maintain a safe working environment, including protecting employees from excessive noise that may cause hearing damage or other health problems.

Question 14

The fundamental hazard associated with excessive noise is hearing loss.

Accepted Answer

Excessive noise can cause damage to the delicate structures inside the ear, leading to hearing loss over time.

Question 15

Noise can be eliminated at its source by enclosing the source.

Accepted Answer

The answer of Noise can be eliminated at its source...

Question 16

Which of the following is the name given to reduction of sound transmission using materials and/or structural elements?
A) Active noise reduction
B) Parallel noise reduction
C) Structural noise reduction
D) Passive noise reduction

Accepted Answer

Passive noise reduction refers to reducing sound transmission using materials and/or structural elements without the use of any external power source or active technology. This includes things like sound insulation, acoustic panels, and double-glazed windows. Active noise reduction (A) involves using technology such as headphones or white noise generators to cancel out noise. Parallel noise reduction (B) and structural noise reduction (C) are not commonly used terms in the field of acoustics.

Question 17

The threshold of hearing is the maximum level of sound that can be perceived without experiencing pain.

Accepted Answer

The threshold of hearing is the minimum level of sound that can be perceived without experiencing pain.

Question 18

With PPE fit is not important in most cases.

Accepted Answer

Fit is important in most cases of PPE to ensure proper protection and minimize the risk of exposure to hazards.

Question 19

Identifying and assessing hazardous noise conditions in the workplace involve which of the following?
A) Conducting periodic noise surveys
B) Conducting periodic audiometric tests
C) Record keeping and follow up action
D) All of the above

Accepted Answer

Identifying and assessing hazardous noise conditions in the workplace require conducting periodic noise surveys to measure the noise levels in the workplace, conducting periodic audiometric tests to assess the hearing health of employees, as well as keeping records and taking follow-up action to address any hazardous noise conditions found. Therefore, all of the above options are necessary for identifying and assessing hazardous noise conditions in the workplace.

Question 20

To decrease the risk of hearing loss, exposure to noise should be limited to a maximum 8-hour, time-weighted average of 90 DBA.

Accepted Answer

This is true as per the Occupational Safety and Health Administration (OSHA) standards for occupational noise exposure. Exposure to noise at or above this level for extended periods of time can cause permanent hearing damage.

Quiz 18: Noise and Vibration Hazards

Sound and vibration are very similar. Which of the following statements are true?

Conducting noise surveys involves measuring noise levels at all locations in the workplace.

The unit of measurement for sound is the decibel, or one-tenth of a bel.

Noise control strategies include which of the following?

Fit testing is not an important prerequisite for effective noise protection.

Sound is any change in pressure that can be detected by the ear.

Noise is distinguished from sound by which of the following factors?

What level of DBA is considered the maximum limit of continuous exposure over eight hour days without protection?