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Solving Noise Hazards of Railroads

As we travel during the course of the day,we are often exposed to the sounds of the environment: trucks and buses honking horns, subways screeching around corners, and trains blowing their whistles at crossings. All these modes of transportation use sound to help keep people aware of their presence and safe from it.And while many of these noises are loud, few are hazardous to those in the vicinity. However, that is not always the case for those operating and managing them.

For example, noise pollution in areas surrounding airports has long been a controversial topic, but the people most at risk from aircraft noise are the people who work closest to them: ground crews, mechanics, baggage handlers, maintenance workers, and others. This is not surprising when you consider the sound of a jet engine can easily reach 140 decibels (dB), well above the pain threshold and loud enough to cause hearing damage after only a few minutes of unprotected exposure.Cabin noise levels in a typical jet engine aircraft at takeoff have been measured between 95 and 98 dB. Turboprop takeoff noise can reach 110 dB, and in-flight noise can reach 90 dB or more for both passengers and crew.

Hearing conservation programs in transportation industries must do double duty. They must protect workers from hazardous noise but also ensure their ability to communicate clearly in their surroundings. The difference between hearing and not hearing a signal to release a brake could mean life or death for transportation workers, passengers, and bystanders.

The Federal Railroad Administration’s Rule
While OSHA covers general industry, aviation, trucking, and bus transportation, the Federal Railroad Administration (FRA) has specific safety standards for freight and passenger railroads and commuter rail. Its Office of Safety focuses on the protection of more than 80,000 railroad employees in the United States as well as passengers, ensuring that people and products arrive at their destination in a safe and timely manner.

In 2006, the FRA issued a new standard for occupational noise exposure among railroad workers. This standard,“ 49 CFR Parts 227 and 229 Occupational Noise Exposure for Railroad Operating Employees,”is very similar to the OSHA Hearing Conservation Standard, except that it places a higher priority on engineering controls. The standard was promulgated by the Railroad Safety Advisory Council (RSAC), which included members from the industry, labor, manufacturers/suppliers, and occupational noise experts. Locomotive engineers, audiologists, and other safety professionals also provided input in developing this standard.

FRA prefaced its ruling with the acknowledgement that “noise is one of the most intrusive aspects of locomotive operations.”Noise sources span a range of engineered sources, such as engines, horns, and brakes; organic sources, such as cab vibration and reflected noise from open windows; and other types of continuous, intermittent, and impact noise.

Just as with the OSHA standard, railroad operators must implement a hearing conservation program when noise levels meet or exceed 85 dBA (8-hour TWA, or Time Weighted Average). The program must include dosimetry (area and personal), audiometry, availability of hearing protection and its mandatory use at 90 dBA, employee training, and recordkeeping.

Unlike OSHA, FRA has a few deviations in its hearing conservation program that focus on the mechanical and less on the personnel/personal.For example, railroad workers are mandated to undergo audiometric testing only once every three years, thus making the detection of noise-induced hearing loss a longer process.

Noise Operational and Engineering Controls
While use of hearing protection devices is mandatory for worker noise exposure of 90 dBA or higher (8-hour TWA), FRA allows “the option of using noise operational controls when employees are exposed to noise levels that exceed 90 dB(A) as an 8-hour TWA.”To promote the use of quieter equipment and eliminate the need for worker use of hearing protection, the standard states that railroads must “obtain and maintain locomotives built to meet the performance standard for maximum noise level in the cab defined by standards in 229.121.”

As a result of concern for worker exposure and in response to the need for more efficient equipment, new locomotive cabs are now being designed to reduce worker noise exposure levels and keep them under the 90 dBA for an 8-hour TWA. This engineering includes moving the placement of horns and brakes away from workers and better cab insulation to keep noise out. At the same time, railroads are forced to place a higher priority on maintaining older equipment to ensure it works efficiently and more quietly.

The FRA standard also states that any hearing protection device (HPD) used must not interfere with crew/radio communications. To avoid overprotection, engineering controls place less responsibility on employees to wear HPDs.

To ensure worker use, FRA does require railroad employees to adhere to the standard, especially in the use of hearing protectors and training. Violation of this standard could result in penalties.

Best Practices: SEPTA
About 600 of the 10,000 employees of the Southeastern Pennsylvania Transportation Authority (SEPTA) are in its hearing conservation program. These employees include engineers, mechanics, infrastructure repair workers, and conductors.

“To maintain track, power, and signals, we need to maintain the health and well-being of our employees. It can be a noisy industry,” said Sharon Sperber, CIH, Safety Officer at SEPTA. “We want to make sure that any [noise-induced hearing loss] is not an occupational injury.”

SEPTA offers its employees a variety of foam ear plugs and ear muffs so workers can choose what they want to wear.When the HPDs are dispensed, each employee receives one-on-one training in proper fit and use of the protectors. To encourage the proper use of protection, SEPTA also uses signs to identify where hearing protection is needed in noisy areas.Employees also will find the class/lot numbers of the ear plugs or ear muffs at hearing protection stations, making reordering easy when inventories are low.

SEPTA also uses the influence of peers to promote proper hearing protection and other PPE use at each location, giving ownership of personal safety to the employees and making safety everyone’s responsibility. This approach utilizes each location’s safety committee comprised of the site manager, a facilities representative, and three to four employees—to be a resource for other employees. These committee members can field questions and act as a positive influence on others.

In line with FRA’s rule, SEPTA will go online with new rail equipment in 2010 that has been designed to be much quieter. The intent is to engineer out the noise and the need for hearing protection. Current locomotive cabs are also outfitted with air conditioning, alleviating the need to open windows and expose engineers to hazardous noise.

Passengers and Hearing Protection
Not only are transportation workers exposed to potentially hazardous noise levels; passengers are, as well. While most noise levels that passengers are exposed to are less than 85 dB, they are exposed to nuisance noise, such as horns, brakes, and other commuters’ conversations. Passengers often act on their own to manage their exposure to nuisance or hazardous noise by using:

Active noise reduction headsets. Also known as “noise canceling headsets,” these ear muff-style devices attenuate low frequencies, up to 1000 Hz.Active noise reduction headsets provide a quieter environment without total isolation. These are ideal for commuters on subways, commuter rail, and airplanes and can be plugged into MP3 players.

Ear plugs. Some people take their commute as time to mentally prepare for the day or relax on the way home. Ear plugs offer a higher level of noise-blocking protection, avoidance of most general ambient nuisance noises, and a high degree of comfort when properly fitted.

MP3 players. Those who use MP3 players for personal listening enjoyment to counteract transit nuisance noise often turn the volume up on their devices, potentially exposing themselves to even more hazardous noise levels.


This article originally appeared in the June 2008 issue of Occupational Health & Safety.

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