Types of Asbestos Survey
Asbestos Survey Type 1
Presumptive (Location and Assessment).
The purpose of the survey is to locate, as far as reasonably practicable,
the presence and extent of any suspect Asbestos Containing Materials
(ACMs) in the building and assess their condition. This survey
essentially defers the need to sample and analyse for asbestos
(or the absence there of) until a later time (e.g. prior to demolition
or major refurbishment). The duty holder bears potential additional
costs of management for some non-asbestos-containing materials.
All areas will be accessed and inspected as far as reasonably practicable
(e.g. above false ceilings and inside risers, service ducts etc.)
or must be presumed to contain asbestos. Any material, which can
reasonably be expected to contain asbestos, must be presumed to
contain asbestos, and where it appears highly likely to contain
asbestos, there should be a strong presumption that it does. All
materials, which are presumed to contain asbestos, will be assessed.
Asbestos Survey Type 2
Sampling survey (Standard sampling, identification
and assessment). The purpose and procedures used in this survey
are the same as for Type 1, except that representative samples
are collected and analysed for the presence of asbestos. If the
material sampled is found to contain asbestos, other similar homogeneous
materials used in the same way in the building can be strongly
presumed to contain asbestos. Less homogeneous materials may require
a greater number of samples.
Asbestos Survey Type 3
Pre-demolition/major refurbishment (Full
access sampling and identification survey)
This type of survey
is used to locate and describe, as far as reasonably practicable,
all ACMs in the building and may involve destructive inspection,
as necessary, to gain access to all areas, including those that
may be difficult to reach. A full sampling programme is undertaken
to identify possible ACMs. This survey is designed to be used as
a basis for tendering the removal of ACMs from the building prior
to demolition or major refurbishment, so the survey does not access
the condition of the asbestos.
Material assessment
The new duty to manage under CAWR will require
a written plan to be produced, specifying the measures to be taken
to control and manage the risk from identified and presumed ACMs.
An important stage of this process is to access the potential fibre
release from each ACM found.
For Type 1 and Type 2 surveys (not
required for a Type 3) the potential for fibre release will be
calculated using the material assessment algorithm set out in MDHS
100. The four main parameters, which will determine the amount
of fibre release from an ACM when subject to a standard disturbance,
are:
 Product type
Extent of damage
Surface treatment
Asbestos type
Each parameter is scored as high=3, medium=2 or low=1, (two categories
allow a nil score). The value assigned to each of the four parameters
is added together to give a total score of between 2 and 12.
Materials
with assessment scores of 10 or more are regarded as having a high
potential to release fibres, if disturbed. Scores of between 7
and 9 are regarded as having a medium potential, and between 5
and 6 a low potential. Scores of 4 or less have a very low potential
to release fibres.
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