What does BG29 2020 say about corrosion monitoring?

25th August 2020

BG29 2020 is BSRIA’s guide to the Precommissioning Cleaning of Pipework Systems. The latest edition was released in April this year.

The updated version of this important document included some significant additions in relation to corrosion monitoring in closed circuit pipework, a solution we have been championing for some time.

The previous edition of BG29 was published in 2012. A lot has changed since then, including our understanding of corrosion and the development of new technologies that monitor the parameters which indicate corrosive conditions.

Why is precommissioning cleaning so crucial?

Precommissioning cleaning ensures closed circuit systems are ready for operation.

Mistakes at this stage can lead to corrosion issues down the line. This can potentially shorten the lifespan of pipework and the associated HVAC plant. Ultimately, this could result in spiralling costs and inefficiencies for the people in charge of the subsequent closed circuit system.

What’s changed in BG29 2020?

Prior to the updates in BG29 2020, the focus for checking corrosive conditions was water sampling; a process that has a number of flaws:

  • Sampling only represents a snap shot in time
  • Results can take days to return, by which time conditions may have changed
  • It focuses on bacteria primarily, and does not successfully detect dissolved oxygen, the precursor to all forms of corrosion.

While sampling is still a part of BG29 2020, the guide now has a big focus on real-time corrosion monitoring.

What is real-time corrosion monitoring?

Corrosion monitoring is mentioned throughout BG29. It is referenced to as a way to check for oxygen, as well as other indicators, such as changes in pressure, that can signify a problem.

In section 2.3.8 the guide states: “Specialist corrosion monitoring equipment is available to measure and record specific corrosion influencing parameters. As a permanent feature of the system, the data recorded can give the maintenance team early warning of conditions likely to promote internal corrosion. This technology allows remote diagnostics so that site visits are minimised.”

We use Hevasure’s 24/7, real-time monitoring solution, which detects a range of parameters – dissolved oxygen, pH, pressure, inhibitor levels, corrosion rates – all signifiers of corrosive conditions. By spotting and dealing with changes in these parameters, corrosion can essentially be stopped before it even starts.

At the precommissioning cleaning stage, corrosion monitoring ensures a closed circuit system is in the best possible condition to be handed over to building owners and facilities managers. It can also be used throughout a water systems life and helps specifiers confidently choose the latest in pipework material.  One such material is thin walled carbon steel. This pipework has many benefits in terms of cost and ease of use, but can be more prone to corrosion.

In section 2.3.6 the guide states that dissolved oxygen levels in the circulating water are measured, with corrosion monitoring used throughout a thin walled carbon steel systems life in order to provide early warning of any issues.

Industry recognition

Getting industry recognition in guides like BG29 2020 is significant. It shows the impact real-time corrosion monitoring is having on the water system management industry, and will hopefully contribute to more long-lasting, efficient and sustainable water-reliant HVAC systems.

For more information about our precommission cleaning services, including Hevasure’s remote monitoring technology, click here.