The BSRIA 6th Edition Pre-commissioning Cleaning Guide Is Out- BG 29/2020 - What You Should Know

Comfort Services Group is a proud sponsor of the BSRIA 6th edition BG 29/2020 Application Guide. The 1st edition of the guide was created in 1991, to provide guidelines regarding pre-commissioning cleaning. Pre-commissioning cleaning, includes the flushing of heating and cooling pipework systems, as well as using biocides and other appropriate measures where needed, to prevent damage to systems. This document is updated continuously as the importance of pre-commissioning is better understood.

We now know that serious operating issues can occur when systems are not pre-commissioned; presence of harmful bacteria in systems is becoming more common and there are always new British and European legal standards to abide by. At Comfort Services Group, we make sure our specialists are well-equipped with the necessary knowledge and skills outlined in these guides, in order to best help our clients determine their pre-commissioning needs. 

In summary, the 6th edition provides new guidance on Corrosion Monitoring, cleaning precautions for Thin-walled Carbon Steel Pipes, Closed-loop Pre-treatment Cleaning (CPC), Pre-treatment options, Corrosion monitoring solutions and new information on heat networks and low carbon systems. Section 3 of the guide, goes into greater detail about inspection and how professionals need to create a sample and analysis plan with target limits for various water quality parameters. Additionally, some new standards have been set.

The key takeaways from the 6th edition that you should know are as follows...

• Guidance on Corrosion Monitoring: there are several different ways to monitor corrosion, such as corrosion coupons, conductivity, dissolved oxygen, pH, water make-up volumes, system flow-rate and operating pressures and metallic corrosion rates.

• Thin-walled Carbon Steel Pipes: are very susceptible to corrosion. It’s now been suggested to simply flush them with clean water, instead of using chemicals or to ask the manufacturer for the best chemical to use if treatment with them is necessary. 

• A closed-loop pre-treatment cleaning is currently known as best practise. Avoid draining the system unless absolutely necessary, measure and monitor system pressures at high points and make sure to measure dissolved oxygen levels in the water. 

• The German Directive VDI 2035: it’s encouraged that professionals read this document. It offers valid water treatment options and in order to implement softened or demineralised water fill options, a design team would need to specify fill additional treatment equipment. 

• Closed Loop Pre-treatment Cleaning (CPC): is a method for cleaning installations by filling them with chemically dosed pre-treated water and dynamically circulating the water through deep bed filter media housings to remove contaminants. 

• The fill-water may also be pre-treated with non-chemical methods such as ultra-violet and other bacteriological removal equipment. CPC can be used when water supplies are limited, when demineralised or softened fill water is used, or when system draining is impractical.

• Sampling and Analysis should include: the objectives of sampling, the numbers and locations of samples to be taken, the analysis to be carried out and guidelines for interpreting results

• Acceptable Pseudomonad Levels: have increased to 1000 cfu/ml at 30 degrees celsius, because previous values were found to be well below the levels that would cause problems. It’s been decided that 1000 cfu is a better estimate of bacterial health.

• Pseudomonads should be tested using a validated laboratory method to ensure that results are reported with cfu/ml as the unit of expression and that the results are comparable with overall TVC counts.

• The management procedures of companies offering or overseeing pipe-cleaning services in compliance with this guide: should ideally be audited under an ISO2000 quality management scheme or by an independent trade association such as the Closed Systems Control Association (CSCA).

At Comfort Services Group, we have 16+ years of experience as trusted leaders in the commissioning industry and are proud to be a sponsor of and abide by the guidelines set by the 6th edition BG 29/2020. We are looking forward to helping you with any of your pre-commissioning needs. Book a free consultation today.