How to Prevent Hearing Damage2nd oct 2012
A new and clever idea using a very low-cost device is now available From Pulsar Instruments plc
Since the Noise At Work Act 2005, employers operating in noisy industries face enforceable limits for noise levels. They are required to make a risk assessment and monitor noise levels to limit long-term hearing loss.
Assessments must be formally documented and an action plan produced.
But once the assessment is undertaken, "what happens next?" In other words, how do those responsible for workers' hearing safety ensure that the noise levels remain inside the permitted limits?
It is difficult to know if the noise exposures have changed unless a new survey is done. Such surveys are not without cost and it is common to assume that nothing has changed.
A new and clever idea using a very low-cost device is now available from Pulsar Instruments plc. The device called the "PulsarSafeEar" is designed to help with this problem. The noise activated warning system continuously monitors the noise levels and, if they reach a pre-set level, the sign illuminates displaying a warning. The warning on the sign can be anything the user requires, but Pulsar has standardised the blue 'noise' logo used internationally.
There are several ways to use the PulsarSafeEar, depending on the noise levels found at the initial assessment, but whatever level is set, it is normally about 3dB below the assessed average level. If, for example, there was no noise more than 80dB(A) during the initial assessment, setting the PulsarSafeEar trigger level to 77dB(A) will reasonably ensure that the 80dB level is rarely if ever breached. However, if the initial assessment showed occasional levels that were high enough to require hearing protectors, the sign can be set to say 80dB(A) and, when this level is exceeded, the sign illuminates to remind the staff to put on their hearing protection. Such selective use is far better than having employees wear hearing protection all the time 'just in case' as most people find them hot and uncomfortable and, in many cases, do not wear them in situations where management does not check. It is worth noting that if the noise level is above the critical level all the time, such a warning will not help and protection must be worn all the time.
Such a device was first proposed some time ago, but the problem was that there was no record of the noise levels and it was hard to prove compliance. The PulsarSafeEar resolves this issue by having an optional data logger that is simply plugged into the USB port on the PulsarSafeEar. This stores 32,000 samples of the slow sound level, technically LAS, and this can be set to store up to 9 hours of the sound levels with a 1-second resolution - such as a normal working shift - or a measurement can be taken every 1 minute when 22 days of data are stored. To read the data, the USB logger is simply plugged into a PC when it can be plotted, analysed and stored. As a result, the unit becomes a true acoustic data logger, but at a cost many times lower than older devices.
The PulsarSafeEar complies with the current International standard for sound level meter as far as is scientifically possible. The basic unit has similar circuitry to Fully Approved sound level meters and is tested in the same way on the same automatic system.
While the design was intended for use in noisy industrial locations, the PulsarSafeEar is finding applications in libraries, schools and hospitals. In these applications, the trigger level is set to a very low level, for example, 45dB(A) to warn when the noise level is becoming obtrusive. In this way, a quiet environment can be re-established without an argument ensuing.
For more information and advice on ways to prevent hearing damage contact the Pulsar team.