Industry works on new commissioning guidance
Over the last year CIBSE, BSRIA, the Commissioning Specialists Association (CSA) and other industry parties have been working on a programme of updates and revisions to the BSRIA guide AG1/2001 ‘Pre-commissioning cleaning of pipework systems’.
This guide deals with the process of flushing and cleaning of the pipework for heating and cooling systems within a building. At the same time revisions are being made to CIBSE Code W, the main change being the inclusion of variable-speed pumping and its effects on valves, valve selection and commissioning — while still retaining the general structure of the code.
The revision to the BSRIA guide (2004) is due to the identification of certain issues relating to the pre-commissioning cleaning of pipework on a number of projects, the result of improvements and developments in building services technology.
To achieve a more informed change, the working group set out to collect as much data on the subject as possible. All parties have agreed to an open forum to include as great a consensus of the industry as possible.
The CSA is in the forefront of this consultation, and at the last CSA AGM, discussions developed around flushing issues that are having a significant detrimental effect on the members and their projects. Some strong opinions were voiced from both commissioning and water-treatment members on what should be addressed and who should be involved. It was agreed that we would take the discussion further, and a special task group was set up to consult with key bodies and companies within the industry.
BSRIA, HVCA, and CIBSE expressed an interest when approached, and a preliminary meeting took place in late June, where BSRIA confirmed funding was available and a timetable was agreed.
An initial group of some 40 delegates, representing commissioning specialists, water-treatment companies and independent consultants met in September 2009 to discuss flushing and water treatment issues and particularly the shortcomings of AG1/2001.
To coincide with our deliberations, at the second BSRIA/CIBSE Code W guidance review meeting, BSRIA agreed to consult formally with CIBSE, HVCA and other stakeholders early in 2010 to determine what revisions they believe are needed. We would then be in a position to set up a joint working group to agree the changes.
The flushing group chairman, Roger Carlin, is currently collating members comments and opinions, and an further meeting is planned for January 2010. The CSA’s aim is to complete the ‘critique’ of AG 1/2001 and formulate recommendations for new guidance.
CIBSE Code W
Throughout 2009 those participating in the re-drafting project of CIBSE Code W (including manufacturers, commissioning engineers, consultants etc.) mapped out a series of changes proposed for peer review in March 2010. The two main areas of focus are ultra-low flowrates and tolerances for proportional balancing.
Unless agreement is reached over these points, it will be designers who may be left with the ultimate responsibility for determining what are acceptable tolerances for these systems.
The industry needs to agree a definition, as there is currently no correlation between the performance achieved and stated tolerances, which begs the question, ‘Do we need to achieve design tolerances or not?’
Nick Till is chairman of the Commissioning Specialists Association and managing director of The Banyard Group.
