Environmental Health and Safety Officer'sNoise Measurement kit
The Environmental Health and Safety Officer's Noise Measurement Kit is a complete set of noise measurement tools that can be configured to meet your exact needs.
The kits contain a combination of an Optimus sound level meter and doseBadge noise dosemeters along with all the required accessories for each instrument. All the equipment is supplied together in a single robust carrying case
The Sound Level Meter chosen to accompany the doseBadge can be selected to suit your requirements and to give you the measurements you need.
Choose your ideal combination of instruments
Simply select the optimus sound level meter and the number of doseBadges that meet your needs.
The doseBadges can be either the standard CR:110A version or the Instrinsically Safe CR:110AIS version which carries ATEX, EEx, IECEx and FM (C & US) certifications.
If you're measuring occupational noise, such as the Noise at Work Regulations, choose from the optimus red (CR:160) Series.
If you need to make environmental noise measurements or if you need to cover both environmental and occupational noise, choose one of the optimus green (CR:170) Series.
A selection of example kits is shown overleaf but remember that a Safety Officer's Noise Measurement Kit can be tailored to your exact requirements.
What's included in the kit?
Each Environmental Health and Safety Officer's Noise Measurement Kit includes the Sound Level Meter, windshield, acoustic calibrator and doseBadges, batteries and power cables, user manuals, quick start guide and calibration certificates.
A sound level meter is used for Acoustic (sound that travels through air) measurements. It is commonly a hand-held instrument with a microphone . The diaphragm of the microphone responds to changes in air pressure caused by sound waves. That is why the instrument is sometimes referred to as a Sound Pressure Level (SPL) Meter. This movement of the diaphragm, i.e. the sound pressure deviation (pascal Pa), is converted into an electrical signals (volts V).
The microphone is distinguishable by the voltage value produced when a known, constant sound pressure is applied. This is known as the MICROPHONE SENSITIVITY. The instrument needs to know the sensitivity of the particular microphone being used. Using this information, the instrument is able to accurately convert the electrical signal back to a sound pressure, and display the resulting sound pressure level (decibels dB).
Sound level meters are commonly used in NOISE POLLUTION studies for the quantification of different kinds of noise, especially for industrial, environmental and aircraft noise. The current international standard that specifies sound level meter functionality and performances from is the IEC 61672-1:2013.
However, the reading from a sound level meter does not correlate well to human-perceived loudness, which is better measured by a loudness meter. Specific loudness is a compressive nonlinearity that depends on level and also frequency, which can be calculated in a number of different ways.
Cirrus Research plc, Casella, 3M, Brüel & Kjær and Rion are a few of global players in this Industry that provide a complete range of fully pattern approved sound level meters.
(SEL), the logarithmic conversion of sound exposure into decibels.
Note: in acoustics all 'levels' are in decibels
PERSONAL NOISE DOSIMETER
A common variant of the sound level meter is a Noise Dosimeter (Dosimeter in American English). However, this is now formally known as a Personal Sound Exposure Meter (PSEM) and has its own International standard IEC 61252:1993.
A noise dosimeter (American) or noise dosemeter (British) is a specialized sound level meter intended specifically to measure the noise exposure of a person integrated over a period of time; usually to comply with Environmental Health and Safety regulations such as the Occupational Health and Safety (OHS) Occupational Noise Exposure Standard.
This is normally intended to be a body-worn instrument and thus has a relaxed technical requirement, as a body-worn instrument—because of the presence of the body—has a poorer overall acoustic performance.
A PSEM gives a read-out based on sound exposure, usually Pa²·h, and the older 'classic' dosimeters giving the metric of 'percentage dose' are no longer used in most countries. The problem with "%dose" is that it relates to the political situation and thus any device can become obsolete if the "100%" value is changed by local laws.
Today, one of the most common devices in use is a miniature PSEM called the doseBadge® also from Cirrus Research, or some similar name by other manufacturers, as it is so small and light that it somewhat resembles a radiation badge. These tiny devices have the three advantages that not only do they not affect the sound field, but they are so small that they do not interfere with the worker in any way and his work pattern does not change; as well, having no microphone cable, they should have a lower risk of failure, by the cable catching on machinery etc.
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