The draft version of BS 8233 was published in June 2025. This standard is one of the most important documents relating to acoustics, and is often used by acoustic consultants and environmental health officers / planners respectively – particularly with regard to the setting of internal noise limits for new residential development.

Part of the work that WBM undertakes for our mineral clients is the reviewing of planning applications for residential developments near to industrial / mineral related sites – which often refer to BS 8233.

The draft standard contains major changes compared to the existing version of BS 8233. Some examples of the main changes with regard to dwellings are listed below:

• The guidance for new dwellings relates to external noise from transportation sources only
• There is no differentiation between different types of rooms
• The approach for dwellings is to categorise the external noise, depending on type of transportation noise and magnitude, and provide a composite sound insulation performance for façades based on the external noise category – although some internal level targets are provided
• External noise affecting dwellings is defined in terms of the Lden and Lnight
• Internal level targets in dwellings are in terms of Lden
• There are no longer any noise level targets for external amenity areas
• There is negligible guidance provided when dwellings are exposed to other types of non-transportation noise (such as commercial/industrial sources), with limited reference to BS 4142 or the ‘agent of change’ principle

WBM has numerous concerns about the draft standard and will be responding formally on the consultation.

Please get in touch if you need a weblink to access the draft standard.

The end date for public comments is 06 September 2025.

Environment Agency ‘Method implementation document’ for BS 4142

The Environment Agency has published a ‘Method implementation document’ (MID) about BS 4142:2014+A1:2019 (BS 4142). This document sets out the Environment Agency’s requirements for BS 4142 assessments that are submitted for a new permit or varying an existing permit

The MID was published in March 2023 and updated in December 2023.

Part of the Environment Agency requirements are that the background sound must not include existing site sounds. During noise measurements, all site activities should be reduced where they no longer contribute to the background level and where they cannot be heard at the measurement location. The background sound level must not include any sound from the site.

This can be problematic for existing sites with current operations. The Environment Agency suggest that the site temporarily stops any noisy operations, or the use of a surrogate monitoring location (with justification).

In addition, the Environment Agency requires the BS 4142 assessment to consider all sound from a site, not just the new or increased portion.

WBM has undertaken many BS 4142 assessments for sites seeking new or varied permits, providing information to comply with the Environment Agencies requirements.

The links for the MID, and also for the noise and vibration requirements for environmental permits are provided on WBM’s website, see:
https://www.wbm.co.uk/documents/