Skip to Main Content »

Construction Case Study


Bam Nuttall are one of the UK’s largest construction companies and are members of the Considerate Constructors scheme.


They were awarded a contract by Transport for London (TfL) for the refurbishment of the northbound carriageway of the Blackwall Tunnel in east London and needed a noise monitoring system for a short period.

As part of the upgrade work, the tunnel’s ventilation shafts were being refurbished and since these are above ground and close to a residential area, the local authority asked for a continuous noise monitor to be installed to access the noise levels.

The purpose of the noise monitoring was to prove compliance with the licensed limit imposed and so reduce the impact of the construction on the local community.

The site engineer also wanted to know the real – time noise levels so any increases could quickly be investigated. The office, however, wasn’t anywhere near the monitoring position.

Blackwell Tunnel


The Type 2250L fitted the bill perfectly 

Enfonic installed an ENV2250L Environmental Noise Monitoring System at the site which continuously monitored the nosie levels in terms of broadband and 1/3 Octave measurements.

The Bruel & Kjaer Type 2250 Sound Level Meter is at the heart of the ENV2250L system and allows modern mobile communications to be used to access the meter from the internet. Using this Web browser functionality, the site engineer was able to see the display of the noise levels from a any computer or mobile device with internet access.

Security was provided by using a user name and password to access the Type 2250 on-line. Two modes of operation are possible; View – which allows users the ability to view the display only and View & Control – which gives expert users added functionality to take full control of the instrument.


  • This was convenient as it wasn’t necessary to install any software and the noise level information could be easily shared by sending a link to colleagues who could view the display simultaneously.


  • The customer also needed regular reports of the noise levels to prove compliance with the licensed limit – this was a requirement from the local authority.
  • Enfonic engineers downloaded the noise data remotely and produced a simple, weekly report of the noise levels. The report was in tabular and graphical form in Excel format so could be easily distributed.

Learn more about our Survey Service .


Suggested Items