Managing the risks of RG22

Are you aware of the risks in using the ubiquitous resin generated foam (RG) that is now used almost universally on fuel sites? Is the assumption that it is risk free putting people in danger? Redhill, Surrey based David Plumb @ Co, Devon based LCM Environmental look at this controversial issue.

The intention of this article is not to say that the supporters of the use of RG foam are all wrong, or that there is no place for it on a fuel site, but that it is not risk free, that those risks should be recognised and the appropriate action taken.

Resin generated foam in its many forms – RG22, RG8 and RG30 – is now widely used on fuel sites everywhere. RG30 is used to encase fuel tanks for extra safety and contamination protection. RG8 is used for filling de-gassed tanks on a very temporary basis, as it is claimed that it can be completely broken down with water. RG22 is the most prevalent, as it is widely used for the ‘permanent’ filling of tanks.

RG22 was first developed at a time when the solid fill material of choice was a 20:1 sand/cement slurry. To fill every part of the tank successfully with this, contractors needed to open the top of the tank, pour in the slurry and agitate it; otherwise it would settle as a cone with space all around. Sometimes part of the forecourt had to be dug up if the manhole had been put in the wrong position.

The advantages of RG22 were that it was claimed to be safe, environmentally friendly and could be pumped in through an exiting pipe or a flange on the manhole lid. This made it a big favourite with petroleum officers and oil companies, some of which began to insist on its use.

It was also cheaper than slurry and much lighter, which meant that the eventual excavation of the tank should be easier and less expensive, as there is no need to hire in a crane, a standard excavator can be used..

Since then, the introduction of foamed concrete has eroded some of these advantages, as it is much lighter than its predecessor and has similar flowing properties. This means that, for most fuel site uses, there is now a viable alternative to RG22 that meets the requirements of oil companies and petroleum officers.

The main reason that we need an alternative is that RG foams contain formaldehyde – a probable human carcinogen.   In 2002, formaldehyde was placed on the US Report on Carcinogens 11th edition, compiled by the US Department of Health and Human Services, Public Health Service and the National Toxicology Program. Something that holds only moral power in the UK and EU.

In Canada Urea-formaldehyde foam, which also uses formaldehyde as a curing aid, was used to insulate homes, particularly timber framed houses, but this has now been banned by the Canadian government after occupants began to complain of runny noses and sore eyes.

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