iPod, Therefore I Hear

Remember the cellular telephone commercial cliché, “Can you hear me now?” Well we have adopted it as our slogan, and test, for use of audio devices in laboratories. What do we mean by “test?” Let us explain.

We know you have noticed the creep of white growths protruding from the ears of more and more people everywhere. Walking down the street, sitting in the movie theater or attending a sporting event, in line or in waiting rooms, ear buds and personal headphones have become ubiquitous. The thing is, now they are showing up in places where they may not be such a good idea, like at work and, in particular, settings where we wander, such as research laboratories.

Should iPods be prohibited in labs?

Many lab managers would ask, “Shouldn’t they just be banned from use in labs?” Our response is that it depends on a number of factors. If there are no extenuating circumstances (more on this below), it really comes down to the test, which goes like this: If you are standing next to someone using ear buds in a laboratory setting and you administer the test in a normal voice, you should get an affirmative response. If you don’t, that person has failed and you need to take action. Because it boils down to whether someone can hear what he or she needs to hear while using personal audio devices.

We believe that most lab managers and employees as well, are aware that excess noise is a problem. Noiseinduced hearing loss (NIHL) is painless, progressive and permanent. And according to all the experts, like the National Institutes of Health (NIH) and the American Conference of Governmental Industrial Hygienists (ACGIH), NIHL is 100 percent preventable. However, we get a lot of push back: What’s the problem with ear buds? My iPod, MP3 player, etc., cannot damage my hearing, right? Unfortunately, the answer is yes they can. Apple iPods with the stock ear buds are capable of producing sounds well above 100 decibels (dB).1 The ACGIH has set a threshold limit value of 85 dB as protective of normal hearing. Therefore, portable audio devices can definitely produce NIHL if used inappropriately.

Although many of the newer devices have a volume limit control built into the software, and this is a good first step in setting the maximum volume, this does not equate to a sound or noise level in decibels. Actual noise levels are a function of the power output of the ear buds or headphones and the type of music or content you are listening to. Without getting too technical, we’ll just say noise is additive to some degree; thus the noise created by auto-samplers, analytical equipment, vacuum pumps, centrifuges, etc., add to the sound level produced by the ear buds or headphones. A good rule of thumb to stay below the protective 85 dB is to ensure that noise, both that produced by the audio device and that produced by laboratory equipment, does not interfere with speech and communication. If it does, this situation can be problematic and even dangerous in busy research laboratories.

For most situations we have adopted the commonsense approach. If you can hear yourself clearly at normal conversation volume, chances are your ear bud or headphone sound level is OK. When we see personal audio devices in use in the lab we give the employee the test, and if the employee responds appropriately we will allow him or her to continue.

Having mentioned the negative effects of environmental noise and recognizing the accompanying tendency to turn up the volume, there are a couple of things you can offer before outlawing ear bud use. New in-ear-canal or noise-cancelling headphones can block an impressive amount of ambient noise.1 By blocking external sound you can listen to your personal audio content at much lower volumes. Another idea is to allow use in “mono mode”—using just one ear bud/headphone and leaving the other ear unobstructed for communication and situational awareness.

When to regulate iPod use

Early on in this article we mentioned that extenuating circumstances might exist that would curtail or prohibit use of personal audio devices in lab settings. We recommend developing a written policy or guideline regardless of your decision to allow or prohibit use so the rules are in black and white for everyone to see. An excellent example is the Audio Device Safety Guideline authored by the Occupational Health and Safety Unit at the University of Queensland.²

Having recognized the explosive growth in use of personal audio devices, your guideline should safeguard iPod use so first and foremost the health and safety of users and coworkers are not adversely impacted. We also agree with the UQ recommendation that everyone receive training on the risks of permanent hearing loss from overexposure to noise, including excessive volume settings on personal audio devices. But the best advice is the requirement to conduct a specific risk assessment and obtain manager or supervisor approval prior to use of any ear bud/headphones in laboratory or workshop settings where:

In summary, control of noise exposure is an important task for laboratory managers. Excessive noise including that from iPods and similar devices makes conversation difficult, affects concentration, distracts workers and increases fatigue. Management of noise exposures includes management of today’s personal audio device technology. If you are overwhelmed or unsure how to handle iPod use, call in a professional and have the risk assessed by someone knowledgeable about sound and its measurement techniques and overall lab safety, such as an industrial hygienist.

• Moving machinery is operated, e.g., centrifuges, lathes, drills, etc., to ensure the risk of entanglement is not increased.
• Infectious organisms are present, e.g., BSL2 or BSL3 laboratories.
• Toxic/carcinogenic substances are present.
• Reduced situational awareness is considered too dangerous.^2,3