Different Methods of Sampling
DIY - (pregnancy tests) - we don't use these
available for self use - they can give readings that will show a positive or negative result.
they give no defined result ie a positive result could be legal level or anything above it.....
it is unlikely to stand up in a court.
some testers use these as a field composite - which makes them very unreliable.
they are easy to get wrong - do bad samples.
Field Composite - we don't usually do these either
these are a lab based test - but one kit is used to take samples from different sites in the house.
Useful and least expensive if doing a due diligence to find if positive or not without locating the actual affected area/areas.
they are cheaper unless a positive result is found.
if positive the tester is required to revisit and take individual samples to isolate the problem area/areas.
Lab Composite - Our prefered method
A lab test where an individual sample is taken in each room.
Several samples are then combined (composited) together in a single lab test
It reduces the cost in the lab rather than doing full tests in each room
It can be decomposited without a further visit if a positive result is obtained.
A definative test result for every sample taken
Multiple Sample Lab Test