Noise assessment equipment
All noise assessments conducted by The Noise Chap use a combination of hand-held and wearable noise meters.
The primary device is a hand held meter, in this case a Class 1 Pulsar Nova Model 45 noise meter. This is a properly nice toy for a noise geek and generates a range of measurement for every noise which is assessed, including:
Average dB(A) for the duration of the measurement
Average dB(C) for the duration of the measurement
Peak dB(C) sound experienced during the measurement
Octave band levels for the measurement.
In these, the dB(A) is used to calculate the exposure against the 85dB(A) limit in the noise regs, while the peak dB(C) is used to compare to the 137dB(C) limit, also in the noise regs.
The average dB(C) level is used in some calculations for how effective hearing protectors are for a given noise level, as is the dB(C)-dB(A) calculation. This gives clients the ability to check how well hearing protectors would perform in the future should they wish to change styles.
The octave band breaks the sound down into various frequency bands and measures the noise levels for each of them. This is the best way to assess hearing protector effectiveness and is used in the noise assessment report for that.
The meter is calibrated by the manufacturer and a copy of the certificate is included in the report, and a daily calibration check is also made before each set of measurements, again verification of this is included in the report.
The secondary devices used are a set of ten Pulsar doseBadges. (For more information on why wearable meters are considered as secondary to hand-held results have a look here).
These are wearable noise meters which are placed on individual employees for longer periods of time and give a measurement of their noise exposure over that time. They are used for that and also to identify any areas of peak noise which can then be investigated further with the hand-held meter. As with the Model 45, calibration certificates are included in the reports and each doseBadge is calibrated before use that day.