The three recognised levels
of asbestos survey are :-
TYPE 1
A WALK THROUGH SURVEY
This gives a general indication of asbestos within the property (without taking samples).
This doesn't establish what is or isn't asbestos - PCL would only recommend this Type 1 as only a forerunner to a Type 2 or Type 3 survey.
TYPE 2
A STANDARD SAMPLING SURVEY
This investigates all reasonably accessible areas (samples are taken and subjected to laboratory testing).
Briefly, this confirms what is or isn't asbestos in all reasonably accessible areas.
TYPE 3
A FULL SAMPLING SURVEY
This generally investigates all areas of the property (again, samples are taken and subjected to laboratory testing).
This expands the Type 2 survey to include sealed voids, underfloor ducts and the more inaccessible areas - usually only done before building works to the area, or demolition.