United Kingdom ▼
Hire > Environmental Meter

Hire of Sound Level Meter for Environmental Noise

environmental sound level meter

The CK171B noise measurement kit is available for hire over a period of one week or longer. This is a top specification meter that is ideal for environmental noise surveys and exceeds the requirements for occupational noise measurement too.

  • Environmental Noise Surveys
  • BS4142 Mixed Residential and Industrial Noise
  • Detailed Noise at Work Assessments

Main features:

  • Class 1 for Accurate and Repeatable Noise Measurement
  • Data Logging with Time History and Environmental Parameters
  • Automatic Timers
  • Audio recording with automatic or manual triggering

Hire Kit Includes

  • Sound Level Meter and Calibrator
  • Software and download cable
  • Calibration Certificates
  • Carrying Case
Hire Period:


The CR171B Optimus Green is a top of the range meter and is fitted with options, such as octave and 1/3 octave band filters, detailed data logging with time history plots, and environmental noise measurement parameters.

This meter also has the Audio Recording feature fitted, making the positive identification of a noise source much easier - you listen to it!


It is essential that a sound level meter meets the correct standards for the measurements you intend to make. Most regulations will indicate the type and grade of meter to use. As the CR171B is a Class 1 (the most accurate version) to IEC 61672 and Type 1 to ANSI S1.43, it is an Integrating meter and fitted with 1/3 octave band filters, it is ideal for most applications.

Environmental Noise

This meter comes complete with data logging, providing a detailed graph of the sound level over time. It also measures the required environmental noise parameters, such as periodic LAeq, LAmax and Ln statistical values.

Automatic timers can be used to make repeating measurements. Many regulations require repeating measurements of 5 minute, 15 minute or hourly duration.

Occupational and Other Noise

As this is a Class 1 Integrating Sound Level Meter, it exceeds the requirements for noise at work assessments. If you need to measure both noise outside and inside the factory then this meter is ideal.

For pure noise at work measurements, please visit the CEL620B2 Integrating Sound Level Meter is more cost effective.


Many regulations state that the meter's function should be checked before starting measurement.

Put the Calibrator on the mic. and select the Calibrate option to do this automatically.


Press the Start key to carry out a manual measurement. Otherwise, use the timers to make 15 minute measurements for example.

All parameters are stored in the meter for viewing or download - no need to choose which measurements you need, they are all there.


Back in the office, the measurements can be viewed on the meter's display or they can be downloaded to a computer.

The hire kit includes the NoiseTools software for downloading and reporting. If you prefer to create your own reports then the noise measurements can be exported to Excel or similar software for maximum flexibility.

StandardsIEC 61672-1:2013 Class 1 or Class 2
IEC 61672-1:2002 Class 1 or Class 2 Group XIEC
IEC 60651:2001 Type 1 I or Type 2 I
IEC 60804:2000 Type 1 or Type 2
IEC 61252:1993 Personal Sound Exposure Meters
ANSI S1.4 -1983 (R2006), ANSI S1.43 - 1997 (R2007)
ANSI S1.25:1991
1/1 and 1/3 Octave Band Filters to IEC 61260 & ANSI S1.11-2004
Measurement Range20dB to 140dB RMS Single Range
Noise Floor<18dB(A) Class 1, <21dB(A) Class 2
Frequency WeightingsRMS & Peak : A, C, & Z Measured Simultaneously
Frequency Bands10 x Octave Bands (31.5Hz to 16kHz)
36 x 1/3 Octave Bands (6.3Hz to 20kHz)
Time WeightingsFast, Slow & Impulse Measured Simultaneously
Memory4GB with 32GB factory fit option
Time History10ms, 62.5ms, 125ms, 250ms, 1/2 sec, 1 sec, 2 sec
VoiceTag AudioUp to 30 seconds of audio notes with each measurement
BluetoothBLE compatible with Android and iOS devices.
Mobile applications available from Google Play and the App Store
Audio RecordingOff, Manual, Threshold Triggered, Advanced Trigger
Studio Quality - 96kHz/32bit WAV format
High quality - 48kHz/24bit WAV format
Standard quality - 16kHz/16bit WAV format
Pre-Trigger function
Integrator Quick settingsEU, OSHA HC & OSHA NC, OSHA HC & ACGIH, MSHA HC & MSHA EC
Ln Statistical Values14 independent statistical Ln values calculated from 1/16th LAF
7 preset to L1.0, L5.0, L10.0, L50.0, L90.0, L95.0 & L99.0
Measurement controlManual, 1 min, 5 min, 10 min, 15 min,30 mins, 1 hour, Lden
Automatic Synchronisation & Repeat
Pause & Back Erase with user selectable duration
DimensionsSize: 283mm x 65mm x 30mm
Weight: 300gms/10oz
PowerBattery: 4 x AA Alkaline
Typically 12 hours with Alkaline AA
Typically 20 hours with Lithium AA Non-Rechargeable
ConnectionsUSB Type B to PC
AC & DC Output via ZL:174 (2 x Phono, 1m)
Multi-pin IO for external power via ZL:171 cable (2.1mm socket)
External Power: 5v-15v via MultiIO socket via ZL:171 cable (2.1mm socket)
CaseMaterial: High Impact ABS-PC with soft touch back & keypad
Tripod Mount1/4" Whitworth socket
EnvironmentalTemperature: Operating -10°C to +50°C, Storage -20°C to +60°C
Humidity: Up to 95% RH Non Condensing
ElectromagneticIEC 61672-1:2002 & IEC 61672-2:2003
IEC 61672-1:2013 & IEC 61672-2:2013
Except where modified by EN 61000-6-1:2007 & EN 61000-6-1:2007
Language optionsEnglish, French, German, Spanish.
Displayed FunctionsLXY, LXYMax, LXYMin, LXeq, LCPeak, LAPeak, LZPeak, LCeq-LAeq, LXE, LAIeq
Graph of Short LAeq, LCPeak
Integrators 2 & 3: TWA, Dose%, Est Dose%
Real-Time 1:1 Octave Bands (Graphical & Numeric)
Real-Time 1:3 Octave Bands (Graphical & Numeric)
Leq LF (20Hz to 200Hz)
Measurement Run Time
14 Statistical Ln values
Stored FunctionsLXYMax & Time History of LXYMax
LAeq, LCeq, LZeq, LCPeak, LZPeak, LAPeak, LAIeq
Time History of LAeq, LCeq, LZeq, LCPeak, LZPeak, LAPeak, LAIeq
Integrators 2 & 3: Lavg , TWA. %Dose
Time History of Lavg
1/1 and 1/3 Octave Bands:Overall Leq & Leq Time History for each band
Ln Values: 14 independent statistical values
Audio recording during measurement
where x=A ,C ,Z; y= F, S, I