Noise Dosemeter (SONUS GA257B)

Model No. Product Name Price Qty
GA257B Noise Dosemeter
GA601 Single Level Class 2 Sound Meter Calibrator
KA010C2 Sound Level Meter Kit Case

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Designed for Industrial Safety Officers and Saftey Managers the GA257B is a dedicated basic dosemeter that is fully compliant with IEC 61252:1993. This meter gives simultaneous sound exposure (LEpd) and maximum peak (Zpeak) measurements, an essential feature for the assessments to the Noise at Work regulations 2005. The dosemeter is designed to be worn by an employee for a full- or part-shift. The results are given in a simple, clear format to give an immediate indication of an employee's daily exposure to noise.

  • Integrated Sound Exposure Level (LEpd)
  • Projected LEpd (8 hour sound exposure)
  • DOSE% and Projected DOSE% (8 hours)
  • 'A' frequency weighting
  • Zpeak - maximum peak level
  • Simultaneous measurement of LEpd, and Zpeak
  • Elapsed time (running time hrs, min, sec)
  • Pa2hr (LEpd expressed in Pascals)
  • Overload indication

  • Alpha-Numeric display for measured results
  • Back-lit LCD panel (8x1 characters)
  • Battery Life (approx. 12 hours)
  • Not supplied with battery

12 Months Certified Calibration

The SONUS GA257B comes with a 12 month certified calibration certificate as standard.

Noise at Work Regulations 2005

This dosimeter is ideal for assessment of compliance to the Noise at work Regulations 2005.

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Technical Specification
Measurement Range 75-140dB
Measurement Parameters LEpd (Sound Exposure Level), PLEpd (Projected LEpd over 8 hours), DOSE% (LEpd compared to criterion level as %) PDOSE% (Projected DOSE% over 8 hours, DOHR (DOSE% per hour), Pa2h (LEpd displayed in Pascal units), Dose per hour, Zpeak (Max. Peak Level)
Instrument Response Simultaneous rms. and Peak
Linear operating range (IEC 61672-1) 70dB
Microphone and Preamplifier Type 2 Pre-Polarised ½” (13.2 mm) Electret Free-Field,
Electret Condenser Microphone: 20Hz – 8KHz ± 2dB –32 dB ± 3 dB re 1V/Pa
Noise Floor Typical ’A’ Weighting <32 dB(A) rms
Frequency Weighting ‘A’ to IEC 61672-1:2013 and IEC 60651:1979
Frequency Range 20 Hz - 8 kHz (including microphone)
1 Hz - 20 kHz (electrical characteristics)
Criterion Level The level at which the 8 hour DOSE% = 100%
User selectable between: 80dB, 85dB and 90dB
Exchange Rate The rate at which the DOSE% doubles.
User selectable between: 3dB and 5dB
Applicable Standards IEC61252-1993 (Personal Sound Exposure Meters)
IEC 61672-1:2013
Processing A to D Converter: 12-bit Controller: 8MHz, micro-controller
Power 1x 9V PP3 alkaline battery (ALR-61) - Life: > 12 hours based on continuous operation
Dimensions 60mm x 35mm x135mm (210mm inc microphone)
Weight 220g inc battery
Calibration Options
12 Month Certified Calibration Issued as standard - Software controlled 91.0 to 120.0 dB (1kHz) in 0.1 dB steps