Free Delivery Over £249*

Next Day Delivery*

60 Day Returns Guarantee

Castle GA257B SONUS Industrial Noise Dosemeter

Castle Group
SKU: CASTGA257B
  • Measures average sound exposure and peak exposure simultaneously
  • 75dB to 140dB measuring range via single linear range
  • Adjustable exchange rate and criterion level
More Info
Typically ships in 5-7 working days

Castle GA257B SONUS Industrial Noise Dosemeter

The Castle GA257B SONUS Industrial Dosemeter is an advanced personal noise exposure meter designed to monitor the sound exposure of employees at work in accordance with the Noise at Work Regulations 1989. It can measure sound from 75dB to 140dB at frequencies between 20Hz and 8kHz. The meter is capable of measuring sound exposure (LEpd) and peak (Zpeak) simultaneously and can also give readings for projected LEpd over an eight-hour exposure. Dose is provided as a percentage and as dose-per-hour whilst actual sound pressure readings can be shown in either decibels or Pa2h.

Frequency weighting is set at A but the criterion level and exchange level are user-adjustable. The one-line, eight-digit screen shows readings clearly and can also show time elapsed, battery level and overload warnings. Operation is undertaken via the simple push-button interface and the 12-hour battery life is perfect for monitoring personal noise exposure over an entire at work. As a SONUS meter, the Castle GA257B is very compact and sturdy enough to withstand the knocks of day-to-day use in industrial environments and complies with regulations such as IEC 61252-1:1993. A pocket clip allows an employee to carry the dosemeter throughout his/her working day.

Castle part number: GA257B

Key Features

  • Measuring range: 75dB to 140dB
  • Max linear range: 67dB
  • Frequency range: 20Hz to 8kHz
  • Integrated sound level exposure
  • Peak, dose, dose per hour, projected dose
  • Adjustable criterion level and exchange rate
  • Meets Noise at Work Regulations 1989
  • Simultaneous average and peak measurement
  • 12-hour battery life
Specification

APPLICABLE STANDARDS

  • IEC 61252-1:1993 (Personal Sound Exposure Meters)

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 Custom pre-amplifier design.

DISPLAY

  • Back-lit LCD panel (8x1 Characters)
  • Alpha-Numeric display for measured results

LEVEL RANGE

  • Measuring Range: 75-140
  • Linear operating range (IEC61672-1): 67dB

NOISE FLOOR

  • Typical ’A’ Weighting <32 dB(A) rms.

FREQUENCY WEIGHTING

  • ‘A’ to IEC 61672-1:2002 and IEC 60651:1979+A1+A2

FREQUENCY RANGE

  • 20 Hz - 8 kHz (including microphone)
  • 1 Hz - 20 kHz (electrical characteristics)

INSTRUMENT RESPONSE

  • Simultaneous Peak and rms

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). 
  • Other Displays: Elapsed time, Overload, Battery Life

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

CALIBRATION

  • Software controlled 91.0 to 120.0 dB (1kHz) in 0.1 dB steps

PROCESSING

  • A to D Converter: 12-bit
  • Controller: 8MHz, micro-controller

POWER REQUIREMENTS

  • Batteries: 1 x 6LR61 (size PP3) 
  • Life: >12 hours (alkaline batteries, continuous operation).

SIZE AND WEIGHT

  • Dimensions: 60mm (width) x 35mm (depth excluding pocket clip) x 135mm (height)
  • Microphone cable length: 800mm (including rubber sleeve and microphone)
  • Weight: 220gms (including battery)