What is THMs?
Trihalomethanes are compounds formed when chlorine reacts with organic material in water.
Why test for it?
THMs are a routine disinfection by-product parameter and are frequently included in filter performance work.
Where can it come from?
- Chlorination of water containing natural organic matter
- Longer residence times in distribution
How is it measured?
Determined by GC-MS on headspace-free samples, reported as individual compounds and as a sum.
What does my result mean?
THM concentrations vary through the year and with distance from treatment.