Product category:
Environmental contamination, noise, dust and fume extraction, sensors
News Release from: Bruel and Kjaer UK | Subject: Noise dose meter Type 4445E
Edited by the Manufacturingtalk Editorial
Team on 18 April 2008
Noise dose meter data collected,
analysed
Noise dose meter enables statistical analysis of noise levels to establish a general 'picture' of the noise situation, showing where excessive exposures stem from.
Bruel and Kjaer's 'intrinsically safe' version of its noise dose meter, the Type 4445E, makes comprehensive noise exposure measurements including within potentially explosive environments Bruel and Kjaer's unique Protector Software for use on a PC enhances the 4445E to perform many post-measurement functions, including making data comparisons and statistical analyses
This article was originally published on Manufacturingtalk on 23 Apr 2008 at 8.00am (UK)
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A statistical analysis of noise levels establishes a general 'picture' of the noise situation.
The 'picture' will show noise level variations.
It will also show whether excessive exposures originate from a generally high noise level or a few isolated incidents.
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The meter can be used in many different work environments, said Bruel and Kjaer to manufacturingtalk, such as factories, chemical plants or construction sites.
The Protector Software can present logged noise exposures, making it much easier to visualise the variation with time of the measured noise levels.
With the data logging tool, numerous measurements can be made over an extended period of time and a time stamp is added to each data point.
This set of time history data reveals a variety of information, including frequency and times when noise levels are excessive.
So it is possible to link noise problems to specific processes or events throughout the day.
It helps users decide whether excessive measured values should be discarded from the record and whether further investigation is needed.
* Timer feature - the timer feature allows an entire week's worth of measurements to be set up, eliminating the user's need to personally attend to each measurement.
The user has only to enter the date and time for the measurements to begin, before switching the noise dose meter on.
The instrument can then be left unattended, until switched off, once the required period of measurement has finished.
Since 2003, all noise dose meters used within hazardous or volatile atmospheres have to have the ATEX (Intrinsically Safe) approval.
Bruel and Kjaer's model meets the requirements associated with ATEX certification code EEx ia I M1 and EEx ia IIC T4 II 1 G, making it particularly suitable for use in dangerous areas such as mines, printing works, petrochemical plants and other areas that require the use of Ex-rated instruments.
Damage caused to workers' hearing by long-term exposure to high levels of noise is the primary cause of occupational hearing loss, yet many are still unaware of the potential for damage.
Noise dose meters such as the Type 4445E are valuable tools in the fight against noise-induced hearing loss, said Bruel and Kjaer.
* Usage - the noise dose meter is worn with the microphone fastened close to the ear.
It measures the sound pressure level and calculates the so-called noise 'dose' received by the individual during the day.
The noise dose is expressed as the equivalent average sound level for an 8h period (reference duration) and this level must be below the limit (or Criterion Level) specified in the relevant occupational health regulation - often an 87dB limit is used.
* About Bruel and Kjaer - Bruel and Kjaer is a world-leading manufacturer and supplier of sound and vibration solutions for use in a wide range of applications including environmental noise measurements, building acoustics, vibration measurements and quality control for use in the automotive, aerospace and consumer industries, as well as by local authorities.
Today Bruel and Kjaer has 900 employees and sales offices in 55 countries.
Bruel and Kjaer is a subsidiary of UK-based Spectris plc.
(www.spectris.com).
Spectris has annual sales of GBP 668m and employs around 5,500 people worldwide in its 13 business units.
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