NoiseMore than just a nuisance

Principles of Environmental Health Sciences

Competencies

• Identify common sources of noise • Recognize adverse health effects associated

with noise• Find and apply information relevant to noise

exposure and health risks

What is noise?

• Common definition: unwanted sound– Sound: Vibrations transmitted through elastic

solid, liquid or gas

• Using subjective definition, people will classify sounds as “noise” differently

Common noise levels

Source: US Occupational Safety and Health Administration

How do we assess noise?

Area or activity measurements

Personal measurements

Exposure models

Auditory effects of noise

• Permanent, irreversible, uncurable noise-induced hearing loss following– Chronic exposure to elevated noise– Brief exposure to extremely high noise

• Profound social, occupational, and psychological impacts

• Typically suffer series of small temporary hearing losses before permanent damage– Test yourself with your car radio!

Non-auditory effects of noise

• Some effects associated with workplace and community noise– Hypertension– Ischemic heart disease– Sleep disturbance– Performance degradation– Annoyance– Psychological effects

Noise exposure Annoyance Effect

Noise exposure

Sleep disruption Effect

Or…

Exposure standards for workplaces

• To protect against noise-induced hearing loss• Permissible Exposure Limit

(enforceable)– 90 A-weighted decibels (dBA)

average in 8-hour shift• “Permissible” level not without risk

– About 1 in 4 workers (!) will have a substantial hearing loss after 40 years

Exposure standards for communities

• To protect against noise-induced hearing loss • Recommended Limit

(not enforceable) – 24-hour average exposure 70 dBA– Protects everyone against

any hearing loss• To protect against annoyance/other effects

– Day or night-time exposures between 30-55 dBA (specific level depends on effect)

7070

Sources of noise in daily life

Others?

Estimated total exposures among sample of ~4500 people in New York City

EPA recommended

annual limit

91% (!) of subjects over EPA limit

from all sources combined; mean

76.8 dBA

Source: Neitzel et al. Exposures to transit and other sources of noise among New York City residents. Environ Science Tech 46(1): 500-8 (2012).

Comparison of noise exposures in daily life in New York City

Source: Neitzel et al. Exposures to transit and other sources of noise among New York City residents. Environ Science Tech 46(1): 500-8 (2012).

What can we reduce exposures to noise?

• Substitution or elimination (avoid exposure altogether)

• Engineering controls (change the noise source to reduce the noise level)

• Administrative controls (limit the length of the exposure)

• Personal protective equipment (wear earplugs or earmuffs to reduce exposure)

Conclusions

• Noise is ubiquitous in community and workplace settings

• Noise has a variety of associated auditory and non-auditory health effects

• There are established health standards for noise from a variety of agencies

• Noise exposure can be reduced through a variety of control methods

Additional resources

• Hearing loss simulator (National Institute for Occupational Safety and Health)– www.cdc.gov/niosh/mining/products/product47.htm

• Online noise meter (National Institute for Occupational Safety and Health)– http://www.cdc.gov/niosh/topics/noise/noisemeter.html

• LAX real-time flight noise monitor– http://ems02.bksv.com/webtrak/lax4

Practice

1. Identify three sources of noise exposure in your own personal life

2. For each of these three sources, identify one way in which you could reduce your exposure

Created by

Rick Neitzel, PhD, CIHAssistant Professor

Department of Environmental Health SciencesSchool of Public HealthUniversity of Michigan