Are you visiting from outside your region? Visit your regional site for more relevant services and pricing.

Member questions: factory air changes, dry riser positioning and animal enclosuresSeptember 2019

Compiled by Maria Thanigasalam, Information Officer, BSRIA

Question: I am about to clean extract only ductwork in a recycling facility. As there is a heavy amount of dust I will be hand scraping and mechanical brushing. Is there any need to do a deposit thickness test after the cleaning? Is there a testing method that can verify cleanliness?

There is a reference on page 24 of BSRIA’s BG49/2015 Commissioning Air Systems, which notes ductwork cleaning standards. The section refers to BESA’s TR19 Internal Cleanliness of Ventilation Systems and also BSI BS EN 15780:2011 Ventilation for buildings. Ductwork. Cleanliness of ventilation systems.

Question: What is the guidance for recommended air changes of a factory, that may intermittently have dust escaping from equipment?

It looks like it should be around 10-15 changes per hour. The Standard you would be looking for is British Standard: BS 5925: 1991 Code of practice for ventilation principles and designing for natural ventilation.

For other general advice on ACH in factories or other types of buildings, you could refer to:

Question: What is the legislation for positioning dry risers in enclosed areas within buildings such as stairwells?

Currently the legal guidance is documented briefly on section 15, page 107 of the latest Approved Document B (fire safety) of the Buildings Regulations.

This document references BS 9990:2006 as the main regulation for dry risers (referred to as dry fire mains) but there is a more recent version, BS 9990:2015.

Question: Are there any articles on Heathrow Terminal 5, as I am trying to find details on how it was serviced and its M&E loads. T5 was opened in 2008.

We do not have exact data on M&E loads or specifics on operational facilities management, but BSRIA Library has many articles and reports dating back to 2008 and before on Heathrow’s terminals, including Terminal 5. Perform a keyword search of the library catalogue on the BSRIA website. Subject coverage ranges from building infrastructure, building services such as lighting and heating, and sound and air quality impact on surrounding areas. Highlights include a case study on building Terminal 5 by ARUP Journal (2016) and an article on lighting and energy efficiency ‘paybacks’ by Building Services & Environmental Engineer (2009).

Question: Are there are any standards for engineering systems criteria for veterinary clinics or surgeries?

All buildings must comply with the standards laid down in the Building Regulations. These standards focus on the construction of the building, energy consumption, insulation. As far as we are aware, there are no special legal requirements relating to vet practices. However, there may be industry standards that are voluntary or that practices must comply with in order to receive some kind of accreditation. Good places to start looking would be the Royal College of Veterinary Surgeons

For other general advice on animal enclosures and animal welfare, you could refer to:

Question: What is the definition of a dead leg - as referred to in BSRIA’s BG29/2012 Pre-commission Cleaning of Pipework Systems? Does this apply to pipe sections full of water, empty or both?

The description of dead legs in Section 2.3.1 at page 11 of BG29/2012 is related to pipework section filled with water that could be subject to stagnation and not allowing circulation of chemicals in use.

Empty pipework sections would not fall under this description.

Note that this approach aligns with the definition of dead leg in HSG274 part 2 (2014): a length of water system pipework leading to a fitting through which water only passes infrequently when there is draw off from the fitting, providing the potential for stagnation.

Management of pipework sections previously wetted as filled and drained/dried is a separate issue, so as pipework section awaiting future connection (see Section 7 of BG29) and should be under the scope of the pre-commission cleaning contractor (the cleaning specialist as mentioned in BG29).

Members can download BSRIA guides for free as well as loan other documents. Contact the library team for more information: or telephone +44 (0)1344 465571.


A unique resource of technical and market knowledge