Page 26 - Gi flipbook June/July 2018

A SOUND ■ making sure the legal limits on

noise exposure are not exceeded
■ maintaining and ensuring equipment
APPROACH ■ providing employees with
provided to control noise risks is used
information, instruction and training
■ carrying out health checks (for
TO HEALTH Across the world it is generally
example monitor workers’ hearing
ability).
AND SAFETY recognised that the noise exposure
limit is 85 decibels (dB). To put that in
perspective, that is quieter than a
hand drill. A hammer drill is about
114dB and a pneumatic drill 119dB. It is
worth remembering that most people
perceive a sound to be twice as loud
Machinery such as turbines within the heart of a power for each increase of 10dB. A
plant results in noise and vibrations which can be harmful to pneumatic drill is therefore more than
workers, local residents and bad for business. Arne Berndt, three times as loud as the
owner and adviser at SoundPLAN, examines steps that can recommended exposure level.
The risk of hearing loss increases
be taken to help mitigate excessive noise with the magnitude and exposure time
and the frequency of the noise, with
oise-related hearing loss and permanent), but there is a myriad higher frequencies doing more damage.
is one of the most of health problems linked to noise, Personal protective equipment
prevalent occupational including sleep disturbance, (PPE) – whether ear plugs or muffs
health concerns across cardiovascular disease and – plays a key role in reducing
N the globe. Various types psychological issues, which may affect unnecessary noise exposure, and a
of noise reduction arrangements and workers or nearby residents. noise contour line should be
suppression apparatus have been Along with the human costs, established wherever people will be
developed to mitigate occupational businesses need to be aware of the subject to levels above 85dB. Beyond
noise within gas-fired power plants likelihood of litigation from workers this line, PPE should be mandatory.
such as that emanating from turbine whose health is affected if the correct Noise maps can help accurately
systems, air-cooled condenser (ACC) steps haven’t been taken to protect establish where this line goes, both
or cooling towers, generators, pumps, them. In addition to the court costs inside and outside a building.
condenser units and associated piping. and potential pay outs, there is the When designing gas-fired power
However, to be fully effective it is management time involved when plants, the industry often ignores
important to understand what type of dealing with issues such as absences noise propagation, believing any
mitigation method will be most and staff cover. potential problems will go away,
appropriate in each setting and exactly Additionally, it’s bad for a business’s provided the plant meets the specified
where it should be positioned. Getting reputation to neglect its employees. maximum noise level of 85dBA within
it wrong can be costly in both Recruitment of new staff and operating areas.
financial and health terms, including customers can be made more difficult If a workplace has areas that may
the expense of retrofitting mitigation if it is perceived as a major issue. be close to or above 85dBA (often the
on major noise-generating equipment, Properly investigating noise levels can case if workers have to shout to make
construction expenses, lost revenue, suddenly seem like a sound themselves heard even in close
costly litigation, and liability damages. investment when faced with this proximity to each other), it is wise to
expensive alternative. invest in a noise study to define all
NOISE IS MORE THAN areas where hearing protection is
JUST A NUISANCE PROTECTING WORKERS required. Alternatively, workers can be
High levels of noise are a problem in As well as health and safety regulations, supplied with noise dosimeters that
any industrial situation as they can many countries have specific noise keep track of their daily dosage of
inhibit worker communication, reducing rules, such as the USA’s Noise Control noise. Although there is an initial
productivity and increasing the chance Act, and the EU’s Environmental Noise monetary outlay with this approach, it
of an accident. High noise levels also Directive (Directive 2002/49/EC). is better than paying for lawsuits from
mean additional personal protective Employers should make sure they are workers with hearing problems and
equipment (PPE) is required. aware of the relevant rules affecting paying for disability because of
Along with these not insignificant their employees. The general tinnitus and hearing loss.
operational issues comes the longer principles include: Sound maps can also reduce the need
term and potentially life-changing ■ taking action to reduce the noise for PPE in the first place, but showing
health effects of exposure to exposure where mitigation measures, including
excessive noise. The most obvious ■ providing employees with personal barriers and replacing noisy equipment,
impact is hearing loss (both temporary hearing protection can help reduce overall noise levels.

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