The Importance of Water Absorption Testing (and Why It’s Not Just a Fancy Name)
Water absorption testing might not sound like the most exciting part of asbestos work, but it’s actually one of the most important tools we have when it comes to making sure asbestos-containing materials (ACMs) are properly identified.
Why does that matter? Because the difference between asbestos cement (AC) and asbestos insulating board (AIB) isn’t just technical—it determines whether the material needs to be removed by a licensed contractor or not. If it’s misclassified, the wrong removal method could be used, which puts people at risk and could lead to serious trouble with the Health & Safety Executive (HSE).
At G&L Consultancy, we don’t take chances. If there’s any doubt about whether a material is AC or AIB, we’ll always recommend a water absorption test. It’s a simple but effective way to make sure the right procedures are followed and that everything stays compliant.
A Real Example
We recently had a case where a client came to us with a sample that had already been tested by another UKAS accredited lab. The result said it was asbestos cement containing both amosite and chrysotile. That raised a red flag as it’s unusual for AC to contain both types of asbestos, so the client wanted a second opinion.
We carried out a water absorption test. The rule is straightforward: if the sample absorbs less than 30% of its weight in water, it’s likely AC. If it absorbs more than 30%, it’s probably AIB.
This sample absorbed 67% which means it was AIB, not AC.
Thanks to the client’s caution and our testing, the job was paused and reclassified as a licensed removal. That meant no one was exposed to unnecessary risk, and the company avoided potential legal issues.
Why We Recommend It
Water absorption testing gives a clear, reliable result when there’s uncertainty. It’s not just about ticking boxes—it’s about making sure the right people are doing the right job, safely and legally.
If you’re ever unsure about an ACM, don’t guess. Get it tested properly. If you want to know more about how it works or whether it’s something you need, feel free to get in touch. We’re always happy to help.
Northern Ireland: 02840 623566
South West England: 01823 443898
