Electronic Level-Dependent Hearing Protectors

Electronic level-dependent hearing protectors prevent hearing loss due to noise overexposure while maintaining users’ awareness of lower-level speech and alarm signals.


Risks Addressed:

Repeated overexposure to noise causes permanent hearing loss and ringing in the ears (tinnitus).  It has also been associated with hypertension and other cardiovascular diseases (Girard et al, 2015).

The Occupational Safety and Health Administration (OSHA) requires that workers’ 8-hour LAeq remain under 90 decibels, while NIOSH has recommended that it remain under 85 decibels. NIOSH’s recommendations are more protective and preferred for maximum hearing conservation. Table 1 shows how long a worker can safely be exposed to different levels of noise (measured in A-weighted decibels, or dBA) according to both OSHA and NIOSH criteria.

 

dBA

OSHA

NIOSH

80

32 hours

>24 hours

85

16 hours

8 hours

90

8 hours

2.5 hours

95

4 hours

47.6 minutes

100

2 hours

15 minutes

105

1 hour

4.7 minutes

110

30 minutes

1.5 minutes

115

15 minutes

28 seconds

120

7.5 minutes

9 seconds

125

3.8 minutes

3 seconds

Table 1

 


How Risks are Reduced:

Electronic Level-Dependent Hearing Protectors (ELDHPs) are similar to traditional (passive) hearing protection devices in that they protect workers’ hearing by blocking harmful levels of noise from entering the ear. However, ELDHPs reduce noise selectively. External microphones on the ELDHP sample sounds outside the protector to determine whether or not amplification is required. When sounds exceed the threshold limit for amplification (typically 82 dB), amplification is reduced to prevent transmission or reproduction of hazardous levels of noise inside the ear canal. Lower-level sounds such as speech or back-up alarms are amplified so that they will be audible without exceeding hazardous levels.

Availability

3M
To obtain information, visit PELTOR LEP-200 and PELTOR WS LiteCom PRO III Headset

Elvex
To obtain information, visit COM-655