Ergonomics tends to be a lesser concern in the realm of laboratory safety, and noise- an ergonomics issue- gets even less attention. Both the Occupational Safety and Health Administration (OSHA) and the College of American Pathologists (CAP) require that noise gets proper notice in the lab. Laboratories of all types must have a policy that outline how workers will be protected from over-exposure to noise. What is over-exposure? How can that be measured? Are you doing what needs to be done to meet these standards?
If you have never measured noise levels in your work area, then it is time to take that first step. OSHA requires monitoring in areas where employees may be exposed to 85 decibels (dBA) as measured over an eight hour Time-Weighted Average (TWA). Many laboratories have noise-generating equipment such as centrifuges, analyzers, Biosafety Cabinets, pneumatic tube systems, and more. Smaller labs and clinics may not have equipment that is noisy, but it is a good idea to at least document a baseline set of readings. If your work area is near or above the 85 dBA limit, you should take measurements on a regular basis. If readings are above 85, you must establish a Hearing Conservation Program for your laboratory, and regular noise readings will be a part of that.
Noise readings can be taken in two different ways, via the use of a noise meter or a noise dosimeter. No matter which equipment is chosen, it must be calibrated. A noise dosimeter is a device that stores sound readings and integrates them over time to provide an average of decibels recorded over that given time. A dosimeter is a small device worn by the employee or placed in a given area. Alternatively, a noise meter may be used. This is a device which records single noise readings. Because the meter cannot provide a noise TWA, it is necessary to take multiple readings in multiple locations throughout the laboratory. I recommend at taking at least five readings per location. Be sure to take readings in all areas where employees perform their duties. When taking noise measurements, make sure the usual lab background noise is present- analyzers should be operating, centrifuges should be spinning, and radios (if present) should be playing. It may be necessary to take individual measurements at different times throughout the day. When using a noise meter, you will have to estimate the overall noise exposure and show that levels are under the 85 dBA limit. If you do not have the equipment necessary for monitoring sound using either method, check with the Facilities or Occupational Health department (if applicable), or you may need to contact an outside vendor who performs such readings.
If the noise exposure is determined to be greater than 85 dBA, then the Hearing Conservation Program must be put into place. The program must include continued regular monitoring of noise levels, audiometric testing of employees, hearing protection, and training. Audiometric (hearing) testing must be offered to all affected staff and be performed by a qualified individual (such as an Occupational Health nurse). Employers must provide hearing protection (such as ear plugs) that fit comfortably and offer sufficient protection. Train employees in the proper care and use of such devices. Employees should also have access to OSHA’s Noise Standard, and complete training on the program should be documented.
Once you have a noise program in place for the laboratory, remember to keep it active. If there is a change in equipment (a new analyzer, fume hood, etc.), or if equipment is moved, new noise readings should be taken. If employees complain about noise in a particular area, do not ignore the complaint- take measurements and report them to the affected staff.
Once noise issues are discovered, there should be no barriers to correcting them. Noise abatement methods may include substitution of equipment, placement of sound-absorbing materials, and the use of sound enclosures. It is rare for those who work in a lab that ear plugs or other sound-reducing tools are needed. However, it is important- and required- to adequately monitor the noise levels in your lab and to keep your staff safe by protecting them against hearing loss. Make noise protection a vital piece of your laboratory ergonomics program.