A One Insulation Limited

MDHS100 Type 3 Asbestos Survey

Full access sampling and identification survey (pre-demolition / major refurbishment surveys)

This type of survey is used to locate and describe, as far as reasonably practicable, all asbestos cement materials 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 asbestos cement materials and estimates of the volume and surface area of asbestos cement materials
made. The survey is designed to be used as a basis for tendering the removal of asbestos cement materials from the building prior to
demolition or major refurbishment, so the survey does not assess the condition of the asbestos, other than to note areas of damage or where
additional asbestos debris may be expected to be present.

Although different types of survey can be specified and used depending on the circumstances, it is important that the building owner, employer
and the surveyor know exactly what type of survey is to be carried out, what the specifications for each type are, and in which areas they are to be
used. It is recommended that the type of survey used conforms to a standard (eg this MDHS), otherwise interpretation of the survey reports will be
difficult and the management plan produced may not adequately minimise the risks involved. It is possible that at larger premises a mixture  of
survey types will be appropriate - eg a boiler house due for demolition will require a Type 3 pre-demolition survey, while offices at the site may
only have a Type 1 presumptive survey.

Similarly, a system-built property may start with several Type 2 surveys, but other similar premises may be evaluated using a Type 1 survey.
Therefore it is important that there is a clear statement and record of the type of surveys that are to be carried out, including that reasons for type
selected, where they are to be carried out, and an estimate of the number of samples to be collected.

All work to be carried out must have an adequate risk assessment of the survey site and the works must be carried out according to the
procedures defined in the risk assessment. The work should minimise the disruption to the client's operations and must protect the health and
safety of all persons who may be at risk. Sampling personnel must wear adequate personal protective equipment, as determined by the risk
assessment under CAWR (eg disposable overalls, overshoes / Wellington boots and a suitable respirator). The type of material sampled and
the amount of disturbance  of asbestos material will dictate the type of respirator. Airborne emissions should normally be controlled by
pre-wetting the material to be sampled, with water and / or a suitable wetting agent. This may involve spraying the surface (eg boards and
sheets) or injecting (eg lagging and sprays). Shadow vacuuming (holding the suction inlet close to the area where dust is being produced) with a
Type H (BS 5415) vacuum cleaner should be used if wetting is likely to be incomplete (eg A/C, AIB boards, ropes and gaskets) or if it is not safe
to to do so (eg it may drip into into electrical installations). Special sampling precautions are used for pipe lagging.

The areas to be sampled inside buildings should as far as possible be unoccupied. Sampling should not be undertaken in normally occupied
areas, but if in constant use, periods of minimal occupation should be chosen. The nature of the area, the likely release of dust and the proximity
and nature of future work will dictate the precautions required to prevent the spread of asbestos. Entry of other people to any sampling area
should be restricted or suitable warnings posted (eg a notice with wording such as Asbestos sampling in progress - keep out). Care should be
taken to minimise the disturbance to the asbestos cement materials and any dust or debris that might be present. Surfaces onto which asbestos
debris may fall should be protected with a sheet of impervious  materials such as polythene which can be easily cleaned by wet-wiping or using
a suitable type 'H' vacuum cleaner. All samples must be individually sealed in their own container or a sealable polythene bag which is then
sealed in a second container or polythene bag. The sample area should be left clean with no evidence of debris from the sampling operation
and any sampling points sealed to prevent the release of fibres. A variety of methods are used to reseal the sampling point.