BSRIA Water Treatment for Closed Heating and Cooling Systems BG 50/2021
![]() |
Contents |
[edit] Introduction
In November 2021, BSRIA published the second edition of its Water Treatment for Closed Heating and Cooling Systems (BG 50/2021). This updated version supersedes BG 50/2013 and is available to purchase from the BSRIA Bookshop. It is also being offered to BSRIA members as a free download.
[edit] Background
Water treatment is essential in closed heating and cooling systems. Without it, there is far greater risk of biological fouling (also known as biofouling), corrosion and scale. These problems can lead to poor performance, system failures and costly remedial works.
BSRIA first published guidance on water treatment in 1993. A major overhaul of this older guide, including a change of scope, occurred in 2013, at which point it was renumbered and renamed: BG 50/2013 Water Treatment for Closed Heating and Cooling Systems.
This guide became widely used in the industry; however, it became clear that it needed an update to bring it in line with current technology and practices and updated standards and guidance. In particular, this revised edition is consistent with Pre-Commission Cleaning of Pipework Systems (BG 29/2021), which was published in February 2021.
The technical content of the publication was written by Dr Pamela Simpson with the help of a steering group, including representatives from the British Chemicals Association (BCA), the Closed Systems Control Association (CSCA), the Industrial and Commercial Heating Equipment Association (ICOM), the Institute of Corrosion (ICorr), the Institute of Workplace and Facilities Management (IWFM) and the Water Management Society (WMSoc).
[edit] What does BG 50/2021 cover?
At present, chemical water treatment is the dominant water treatment technique for closed heating and cooling systems in the UK. Therefore, this technique is covered in depth in the guide. Other techniques are also available, and a number of these are covered in the guide, including:
- Pre-treatment of fill water.
- Removal of dissolved gases.
- pH management.
- Solids removal and filtration.
- Galvanic anode cathodic protection/electrochemistry.
- Bacteria and biofouling inhibition by biocides.
Expanded guidance has been provided on the roles and responsibilities of those typically involved with water treatment in closed systems: planners of water treatment programmes, maintenance water treatment specialists, day-to-day system operators, building owner/operators and remedial cleaning specialists.
The suggested water quality analyses and guidelines have been updated, including the addition of corrosion rates. Additional guidance has been provided on corrosion monitoring and on-site testing, including the use of test kits.
This article originally appeared on the BSRIA website under the headline, 'BSRIA launches update to Water Treatment for Closed Heating and Cooling Systems'. It was published in November 2021.
--BSRIA
[edit] Related articles on Designing Buildings
- Biological fouling.
- BSRIA articles on Designing Buildings Wiki.
- Chilled water.
- Closed system water treatment: BG 50 & VDI 2035.
- Commissioning building systems.
- Heating ventilation and air conditioning.
- Pipework.
- Training for pre-commissioning cleaning of pipework systems.
- Water treatment.
[edit] External resources
Featured articles and news
RTPI leader to become new CIOB Chief Executive Officer
Dr Victoria Hills MRTPI, FICE to take over after Caroline Gumble’s departure.
Social and affordable housing, a long term plan for delivery
The “Delivering a Decade of Renewal for Social and Affordable Housing” strategy sets out future path.
A change to adoptive architecture
Effects of global weather warming on architectural detailing, material choice and human interaction.
The proposed publicly owned and backed subsidiary of Homes England, to facilitate new homes.
How big is the problem and what can we do to mitigate the effects?
Overheating guidance and tools for building designers
A number of cool guides to help with the heat.
The UK's Modern Industrial Strategy: A 10 year plan
Previous consultation criticism, current key elements and general support with some persisting reservations.
Building Safety Regulator reforms
New roles, new staff and a new fast track service pave the way for a single construction regulator.
Architectural Technologist CPDs and Communications
CIAT CPD… and how you can do it!
Cooling centres and cool spaces
Managing extreme heat in cities by directing the public to places for heat stress relief and water sources.
Winter gardens: A brief history and warm variations
Extending the season with glass in different forms and terms.
Restoring Great Yarmouth's Winter Gardens
Transforming one of the least sustainable constructions imaginable.
Construction Skills Mission Board launch sector drive
Newly formed government and industry collaboration set strategy for recruiting an additional 100,000 construction workers a year.
New Architects Code comes into effect in September 2025
ARB Architects Code of Conduct and Practice available with ongoing consultation regarding guidance.
Welsh Skills Body (Medr) launches ambitious plan
The new skills body brings together funding and regulation of tertiary education and research for the devolved nation.
Paul Gandy FCIOB announced as next CIOB President
Former Tilbury Douglas CEO takes helm.
UK Infrastructure: A 10 Year Strategy. In brief with reactions
With the National Infrastructure and Service Transformation Authority (NISTA).