Sound Level Meters

CEL620A Integrating Sound Level Meter


The CEL620A is an Integrating Sound Level Meter that provides you with all the measurements needed for a detailed noise at work survey and subsequent hearing protection assessment.

  • Occupational noise measurement
  • Hearing protection assessment
  • Data logging with download to computer
  • Quick and easy to use
  • Simultaneous measurement of all parameters (LAeq, Max, Min, etc)
  • Single range 20 to 140 dB


  • IEC 61672 - Class 1 or Class 2
  • IEC 60651 and IEC 60804 - Type 1 or Type 2
  • European Physical Agents (Noise) Directive 2003/10/EC

Integrating Sound Level Meter

The CEL620 provides a large set of parameters, such as "A" and "C" weighted Max, Min and Peak. As an Integrating sound level meter, it also provides the average sound level Leq. All measurements are made in parallel, which means you do not need to decide beforehand which ones you need - they are all stored.

Noise at Work Regulations

The EU noise at work regulations - Physical Agents (Noise) Directive 2003/10/EC - and the UK HSE guidelines (Controlling Noise at Work) state that noise measurements should be made using a calibrated Class 2 Integrating Sound Level Meter capable of measuring the "A" weighted Leq (LAeq). For environments with loud banging noise the meter should also measure the "C" weighted Peak (LCpeak).

All the CEL620 models meet these requirements and so are perfect for a noise at work assessment. These meters also have the "C" weighted Leq, which can be used to check the suitability of hearing protectors.

Data Logging and Software

The CEL620 comes complete with data logging capability with measurements stored in the meter's internal memory. When connected to a Windows computer, the meter acts like a memory card (shows as a removable drive) so the measurements can be loaded into a spreadsheet or moved to your hard drive for long term storage. There is no need to buy and install special software, which can be a real benefit on a company networks where installation of software is not encouraged.


Our Recommendation

For noise at work measurements, we recommend order code CEL620A2-K, which includes the Class 2 CEL620A2 and Calibrator. The standard meter is data logging and measurements can be transfered to a spreadsheet.


As an Integrating meter available as either Class 1 or Class 2, the CEL620A has many applications. However, its primary application is for assessing worker noise exposure.

  • European Noise at Work Regulations
  • USA, Canada and most other regulations
  • Hearing protector checks (SNR or HML method)
  • Environmental noise surveys (see notes below)
  • Machinery testing

Most noise measurement regulations will specify the type and grade of sound level meter that should be used. Some regulations, such as the European noise at work regulations, specify that an Integrating sound level meter should be used. For others, such as the OSHA regulations in the USA, do not demand an Integrating meter, but it makes the measurement process much easier and more reliable.

Regulations should also specify whether a Class 2 or the more accurate Class 1 meter should be used. For most occupational noise assessments, including the EU and UK regulations, a Class 2 is adequate.

occupational noise

Noise at Work

The European noise at work regulations state that you should use at least a Class 2 Integrating Sound Level Meter. The meter should be verified by a suitably equipped laboratory when new and then at least every two years. You also need a Calibrator to check the meter's function before making measurements.

An Integrating meter like the CEL620 provides you with the measurement of the average sound level - LAeq. Rather than trying to average the sound level by eye (made more difficult by the logarithmic nature of noise), the meter does the averaging for you. The LAeq is then used to calculate the worker's daily noise exposure level, or Lep,d.

Hearing Protection Assessment

When the noise levels are particularly high (e.g. greater than 90 dBA) then you should check that the hearing protection provided is adequate. If it does not reduce the noise at the ear to an acceptable level then clearly it is not adequate. The CEL620A measures both the A and C weighted sound level, so you can use the SNR or HML method. The CEL620B has Octave Band Filters, so the more detailed Octave Band method can be used - recommended for very high noise levels or high tonal content.


Environmental and Community Noise

As the CEL620 is available as either Class 1 or Class 2 and includes data logging, it is suitable for many environmental noise surveys.

However, we would recommend the CEL633 Environmental Sound Level Meter as it includes additional noise measurement parameters (needed for some regulations, but not all), automatic timer functions and a removable preamplifier so it can be used in an outdoor kit.

Occupational Noise

The CEL620A2 was designed specifically for noise at work measurements in line with the EU regulations. It provides all the noise measurement parameters that you need in a meter of the correct grade.

This meter can be used without a computer, reading the measurements from the screen. Even in its standard form it stores the measurements and these can be downloaded manually into a Spreadsheet (Excel or similar). The Insight software is also available for more convenient download, storage and reporting.

  • Designed for occupational noise regulations
  • Meets the required standards
  • All parameters needed: LAeq, LCPeak
  • Storing and download to computer
  • Colour coded display for ease of use

The full occupational noise measurement process is described below.

1. Calibration Check

The regulations and guidelines state that the meter's calibration should be checked before making measurements, and that you should keep records of these calibration checks.

Fit the Calibrator over the microphone as shown on the right and switch it on. The meter automatically detects the presence and correct fitting of the Calibrator and then starts the calibration process, which only takes a few seconds.

Calibration details are stored in the meter so that you can either make note or download them to a computer.

calibrating the meter
Calibration Check

2. Start and Stop Measurements

To start a measurement, simply press the Run/Stop key, shown on the right.

This starts the measurement and storing process for all parameters, the most important for noise at work being the LAeq and Peak. If the meter has Octave Band Filters fitted then these measurements start too.

When you are happy that you have measured for long enough (the average level has settled for example), simply press the Stop key.

start noise measurement
Starting a Measurement
Not Running

Colour Coded Display

The current state of the sound level meter can be seen at a glance.

When not running the meter shows the current sound level and the border is red.

When running the meter shows the measurement parameters such as Leq or Lavg and the border is green.


View the Results

The measurements can be viewed on the meter's display or they can be downloaded to a computer. There are three download methods (one of which is free of charge with the meter).

The basic model (order code CEL620A2) is a Class 2 Integrating Sound Level Meter and so meets the requirements of the noise at work regulations. The main options are:

  • Class 1 or Class 2? - Most regulations say Class 2 is adequate.
  • Accessories? - Calibrator is often essential, carrying case is useful.
  • Insight Software? - Makes download and analysis more convenient


Sound Level Calibrator

sound level calibrator

The most important of the accessories is the Calibrator. The regulations state that you should use one to check the function of the meter before making any measurements.

Class 1 or Class 2 Sound Level Meter?

A Class 1 sound level meter is a little more accurate than a Class 2 model. It is also more expensive. If you are using the meter exclusively for noise at work assessments then the EU regulations and HSE guidelines are quite clear: Class 2 is adequate. For this reason we recommend the Class 2 model.

However, if you need to make other noise measurements, such as noise emitting from your factory into the local environment, then it might be wise to go for a Class 1 meter.


The CEL620A is a data logging meter that does not require any additional software - when plugged into a computer it acts like a memory card. You can manually copy the data to your computer or load it into a spreadsheet program or you can make use of our web based NoiseMeters Applications. The Insight software option makes this process more convenient, links the measurements to person, place or process, and presents the results.

Order Codes

Sound Level Meter CEL620A1 - Class 1 Integrating Sound Level Meter £1515.00
  CEL620A2 - Class 2 Integrating Sound Level Meter £1047.00
Calibrator The Calibrator is available as Type 1 or Type 2, usually to match the class of the meter:  
  CEL120/1 Type 1 Sound Level Calibrator £515.00
  CEL120/2 Type 2 Sound Level Calibrator £252.00
Software NMAPPS NoiseMeters Applications £65.00
  ISC020 Insight Software £295.00
Accessories CEL6840 Carrying Case for CEL620 Sound Level Meter, Calibrator and accessories £74.00
  PELI-SLM Peli Case for CEL Sound Level Meter, Calibrator and accessories. £175.00


The CEL620A is a data logging Integrating Sound Level Meter, available as either Class 1 (CEL620A1) or Class 2 (CEL620A2) as defined by the international sound level meter standards.


Sound Level Meter Standards

  • IEC 61672 Class 1 or Class 2
  • IEC 60651 and IEC 60804 Type 1 or Type 2
  • ANSI S1.4 and ANSI S1.43 Type 1 or Type 2


Using a meter that meets these standards is essential for repeatable results and especially for any measurements that will be used for legal purposes.

Technical Specifications

Measurement range 20 to 140 dB (single range), 143 dB Peak Measured Parameters  
Display 320 x 240 pixel color TFT Frequency weightings A, C and Z (simultaneous)
Output to PC USB Mini B Time weightings Fast, Slow and Impulse
    Amplitude weightings Q3, Q4 and Q5
Batteries 3 x AA Alkaline Thresholds 70 to 90 dB (applies to Lavg)
  (20 hours with backlight off)    
External Power 9 to 14V DC at 250mA Sound Level LXY, LXYMax, LXYMin
  (2.1mm connector) Integrated LXeq, Lavg, LAE
    Peak LXPeak
Measurements stored 100 Takt Max LTM3, LTM5, LXIeq
Dimensions 72 x 229 x 31mm, 295g    
  2.8" x 9.0" x 1.2". 10.4oz    

Prices and Ordering

The Class 2 Integrating Sound Level Meter can be bought on its own or as part of a measurement kit.

Order Code
Price (GBP)
Type 2 / Class 2 Integrating Sound Level Meter
Kit with CEL620A2 Sound Level Meter, Calibrator, Windshield, Case
NoiseMeters Applications Web Based Noise Reports
Insight Software for CEL620, CEL630 and dBadge

The Class 1 Integrating Sound Level Meter can be bought on its own or as part of a measurement kit.

Order Code
Price (GBP)
Type 1 / Class 1 Integrating Sound Level Meter
Kit with CEL620A1 Sound Level Meter, Calibrator, Windshield, Case
NoiseMeters Applications Web Based Noise Reports
Insight Software for CEL620, CEL630 and dBadge

Individual items and spares for the CEL620 series meters.

Order Code
Price (GBP)
Class 2 Acoustic Calibrator
Class 1 Acoustic Calibrator
Case for CEL240 and 600 Series Sound Meter and Calibrator
Peli Case and Foam for CEL Sound Meter and Accessories
Windshield for CEL240 and 600 Series Sound Level Meters


The CEL620B2-K Noise Measurement Kit is available for hire. The hire includes the following items

  • CEL620B2 Sound Level Meter with Real-Time Octaves
  • CEL120/2 Sound Level Calibrator
  • Carrying Case
  • Insight Software

First week: £199.00 then £25.00 for any additional days. Price includes delivery and collection.

Delivery Charges within the UK

These delivery charges are for Sound Level Meters and Noise Measurement Kits within mainland UK.

Meters and Kits £12.00  
Small Spares £6.00  

Value Added Tax - VAT

VAT is charged at 20% on all our products shipped to a UK address or invoiced to a UK address.

Contact Midas

Midas Safety Services are happy to discuss your Sound and Noise Level Testing requirements and arrange a no-obligation meeting if that would be helpful.

Please contact us on 0117 318 2163/0776 232 3367 or email

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cel620a noise at work sound level meter

CEL620A Sound Level Meter

Product List:


General purpose sound level meter which is very easy to use.

CEL620B Octave Band sound level meter

A practical meter perfect for a detailed noise at work survey and subsequent hearing protection assessment.


Class 2 Sound Level Meter.


Data Logging Integrating Sound Level Meter.

Dosebadge Kits

The doseBadge is a unique solution for Personal Noise measurements.


Noise Dosemeter and Handled Meter Combinations.


Environmental Sound Level Meter


CEL633C Environmental Sound Level Meter with 1/3 Octaves