Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Study of NYC transit system noise levels finds daily rides can result in hearing loss

12.10.2006
Levels often exceed recommended exposure guidelines

In a new survey of noise levels of the New York City transit system, researchers at Columbia University's Mailman School of Public Health found that exposure to noise levels in subways have the potential to exceed recommended guidelines of the World Health Organization (WHO) and the U.S. Environmental Protection Agency (EPA).

According to the research, as little as 30 minutes of exposure to decibel levels measured in the New York City transit system per day has the potential to result in hearing loss. The findings have just been published in the September issue of the Journal of Urban Health, a publication of the New York Academy of Medicine.

"Noise exposure and noise-induced hearing loss is a global health problem of significant magnitude, especially in urban settings, yet published data are extremely limited," said Robyn Gershon, DrPH, professor of Sociomedical Sciences at the Mailman School of Public Health and lead author of the study. Dr. Gershon and co-authors report that the findings suggest that, "Daily exposure to noise on subway platforms and subway cars has the potential to cause hearing loss. At the highest level obtained on the platform (106 decibels), the allowable limit under WHO and EPA is only 30 seconds. More than 1 in 10 of the platform measurements exceeded 100 decibels -- which translates into an allowable limit of only 1.5 minutes."

Further, Dr. Gershon notes that "maximum levels inside of subway cars were even greater, and could lead to serious exposures, although more research is needed to determine exactly how much exposure that frequent, long distance, long-term riders experience." This research by safety experts at the Mailman School is the first scientific subway noise assessment in over 30 years, and believed to be one of only two papers published on NYC subway noise; the last one was in the 1930s.

Average and maximum noise measurements were made using a precision sound level meter on subway platforms located in the four New York boroughs with underground subways (Manhattan, Brooklyn, the Bronx, and Queens). The average maximum noise level on subway platforms measured was 94 decibels (dBA). The average maximum inside of subway cars was 95 dBA, and at bus stops, the average maximum was 84 dBA. For comparison, approximate levels of familiar sounds are: 45-60 dBA for normal conversation, 100 dBA for a chainsaw and 140 dBA for a gunblast. The logarithmic nature of decibels means that every 10 dBA equals a 10 fold increase in intensity. Thus a 90 dBA sound is 10 times as intense as an 80 dBA sound.

"Several factors have the potential to contribute to hearing loss, including years of ridership, frequency of ridership, and length of rides," observes Dr. Gershon. If a rider is exposed to other high noise-level activities such as a personal listening device, the potential for hearing loss is even greater." Dr. Gershon further notes that even short exposures to very high noise levels can cause the same amount of damage as much longer exposures at lower levels.

To determine if noise levels varied by location on the subway platforms, measurements were made at three different locations on each platform: the front end, the middle section, and the rear section of the platform. For all measurements, other conditions that could affect noise levels, such as passing trains, air brake release, police sirens, subway musicians etc., were also noted.

Earlier research by Columbia University's Mailman School of Public Health offered a comprehensive look at subway-related health and safety hazards that might affect both riders and subway workers. While this assessment found that subways in general, and the New York City subway system in particular, are relatively safe, especially in comparison to automobile use, they may be associated with a wide range of potential health hazards.

The New York City subway system is the largest and the second oldest system in the U.S., with over 450 subway stations, 500 subway trains, and over 2,000 miles of track. Operating 24 hours a day throughout NYC, it has almost 4 million riders per weekday, which is the fifth largest ridership in the world.

Because excessive noise exposure can ultimately result in noise induced hearing loss, Dr. Gershon notes that risk reduction is the best strategy. Many steps have been taken and continue to be taken by large transit systems, including the Metropolitan Transit Authority, to help reduce subway noise. Steps that individuals can take include the use of personal hearing protection devices (e.g., earplugs and earmuffs). The use of cotton or fingers only reduces the noise levels slightly. The use of personal listening devices, which many may think is protective, can actually contribute to noise exposure if they are played at high volumes. Public education and awareness on hearing protection in general, is highly recommended.

Stephanie Berger | EurekAlert!
Further information:
http://www.columbia.edu

More articles from Studies and Analyses:

nachricht Win-win strategies for climate and food security
02.10.2017 | International Institute for Applied Systems Analysis (IIASA)

nachricht The personality factor: How to foster the sharing of research data
06.09.2017 | ZBW – Leibniz-Informationszentrum Wirtschaft

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Neutron star merger directly observed for the first time

University of Maryland researchers contribute to historic detection of gravitational waves and light created by event

On August 17, 2017, at 12:41:04 UTC, scientists made the first direct observation of a merger between two neutron stars--the dense, collapsed cores that remain...

Im Focus: Breaking: the first light from two neutron stars merging

Seven new papers describe the first-ever detection of light from a gravitational wave source. The event, caused by two neutron stars colliding and merging together, was dubbed GW170817 because it sent ripples through space-time that reached Earth on 2017 August 17. Around the world, hundreds of excited astronomers mobilized quickly and were able to observe the event using numerous telescopes, providing a wealth of new data.

Previous detections of gravitational waves have all involved the merger of two black holes, a feat that won the 2017 Nobel Prize in Physics earlier this month....

Im Focus: Smart sensors for efficient processes

Material defects in end products can quickly result in failures in many areas of industry, and have a massive impact on the safe use of their products. This is why, in the field of quality assurance, intelligent, nondestructive sensor systems play a key role. They allow testing components and parts in a rapid and cost-efficient manner without destroying the actual product or changing its surface. Experts from the Fraunhofer IZFP in Saarbrücken will be presenting two exhibits at the Blechexpo in Stuttgart from 7–10 November 2017 that allow fast, reliable, and automated characterization of materials and detection of defects (Hall 5, Booth 5306).

When quality testing uses time-consuming destructive test methods, it can result in enormous costs due to damaging or destroying the products. And given that...

Im Focus: Cold molecules on collision course

Using a new cooling technique MPQ scientists succeed at observing collisions in a dense beam of cold and slow dipolar molecules.

How do chemical reactions proceed at extremely low temperatures? The answer requires the investigation of molecular samples that are cold, dense, and slow at...

Im Focus: Shrinking the proton again!

Scientists from the Max Planck Institute of Quantum Optics, using high precision laser spectroscopy of atomic hydrogen, confirm the surprisingly small value of the proton radius determined from muonic hydrogen.

It was one of the breakthroughs of the year 2010: Laser spectroscopy of muonic hydrogen resulted in a value for the proton charge radius that was significantly...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ASEAN Member States discuss the future role of renewable energy

17.10.2017 | Event News

World Health Summit 2017: International experts set the course for the future of Global Health

10.10.2017 | Event News

Climate Engineering Conference 2017 Opens in Berlin

10.10.2017 | Event News

 
Latest News

Electrode materials from the microwave oven

19.10.2017 | Materials Sciences

New material for digital memories of the future

19.10.2017 | Materials Sciences

Physics boosts artificial intelligence methods

19.10.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>