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About
MDHS |

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Methods
of Determining Hazardous Substances 100 (MDHS 100).
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The
Need for Tighter Controls when Working in Areas where Asbestos
Materials may be found.
Asbestos is responsible for more cancer deaths than all
the other known occupational hazards combined. There are approximately
3,000 asbestos related deaths in Britain per annum and the figure is rising. The trend is similar throughout Western Europe,
where a quarter of a million mesothelioma deaths may occur over the next 35 years. The number of
cancers of the lung caused by asbestos is uncertain but is likely to be at least as high. |
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Construction workers, including plumbers, electricians, and carpenters, constitute the main high-risk group, and studies of
asbestos in victims' lungs indicate that cases with no known occupational origin are often due to unrecognised past exposure. Most mesotheliomas now occurring are due to asbestos exposure prior to 1980 when asbestos was in widespread use,
particularly in the construction industry. Much of the asbestos used in construction between 1960 and 1980 is still in place,
however, and this can still cause substantial exposure to construction workers involved in renovation, maintenance,
demolition or asbestos removal.
The consequences of asbestos
exposure have been known for many decades. The asbestos risk was first reported almost 100 years ago, and the risks of
lung cancer and mesothelioma have been known for 40 years. With the benefit of hindsight it seems extraordinary that
uncontrolled use remained widespread, particularly in the building industry, until the 1980s.
The only way to ensure a safer future is by ensuring that information on practical risk
management is widely available. |
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The aim of the Asbestos Register.
The new legislations, due to be introduced in May 2002,
will provide property owners and managers with a two year period, from that date, to carry out an asbestos survey and compile an asbestos register for each property that he or she
has responsibility for.
The main aim is to minimise the exposure of contractors and the public to
asbestos by supply contractors with a copy of the site asbestos register notifying them of the known asbestos within the building. If a non-intrusive survey has been carried out it would warn of the possibility of further asbestos being present within the structure and the need to exercise caution when carrying out
works.
It will also act as a precautionary measure for the emergency services when
there is a danger of asbestos being exposed during fires etc. |
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The form of the survey.
The form of the survey will be determined by the nature of the site and the future use to which it will be put. It will be essential that the building owner or employer specify the type of survey to be carried out in order that the results will be appropriate to the future needs of the site. The employer should understand the limitations of each survey type. In general, three types of survey are
recognised:-
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Walk through survey. A walk through survey is the simplest type of survey that can be
undertaken. It will probably not include sampling and there may be very limited access into some areas such as:
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Ceiling voids
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Risers
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Under floor ducts
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Plant rooms
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Excluded areas would also include restricted access for security or operational reasons. An example being an intensive care unit of a hospital in use 24 hours per day.
There may be some situations when it is impractical to gain access to areas or voids but it is strongly suspected from plans, the age of the building, anecdotal information or other sources that asbestos materials may be present. If there is a strong presumption that asbestos is present in an area not accessed, or if fibres can be seen in a material not sampled, there should be some assessment of the risk that the materials may present to the occupants of the area.
Limitations of a walk through survey. The results from this type of survey are evidently very restricted and the limitations must be clearly stated in any report. The areas where no access has been gained should be clearly identified (and presumed to contain asbestos until accessed, surveyed and proved otherwise). If work is to be carried out in any area not accessed then there must be further investigation and sampling before proceeding with any work which may disturb asbestos. Building owners or managers should not normally commission such a survey without very good cause and a clear understanding of the limitations.
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Invasive survey. This is the normal type of survey, appropriate for the routine maintenance of a building or site. It locates, samples and accesses all asbestos containing materials, so far as is reasonably practicable. The information produced can more confidently be used as an action plan to minimise the risk of exposure to asbestos for occupants and maintenance operatives. The survey must be carried out in such a manner as to minimise the damage to the building fabric and
decoration. It would not be normal to exclude asbestos materials regarded as "low risk" such as asbestos cement products or bonded composites.
The survey should aim to identify all asbestos materials in the building fabric, including for example the use of proprietary products such as "Rawplastic" or "Screwfix" which were used as plugging compounds, but these will normally only be detected where the fixings have been removed. There may still be limitations on access during the survey and any such limitations must be clearly identified. Ideally, surveyors should use a "positive entry" system so that any part of the register with no data entry means that the area has been accessed and no asbestos was found to be present, unless it is stated that access was not possible.
It is important to remember that even though a survey has been done, all asbestos on a site may not have been discovered or identified. Any area that cannot be accessed or has not been explored must be assumed to contain asbestos.
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Pre-Demolition Survey. This type of survey is used to locate all asbestos materials prior to demolition or major refurbishment of the property and
/ or site. It will be more destructive in sampling the structural components, such as partitions. Materials regarded as impracticable to sample in other surveys (enclosed or difficult to reach) should be sampled during this type of survey.
In this case, there will be the need to assess the extent of the materials (to specify the scope of works during removal) but no need for a condition risk assessment or recommendations on remedial action other than removal under controlled conditions. It must be understood that some asbestos materials may be located within the structure and not found until demolition of the building. Occasionally old pipe-work is found plastered over, or bricked up, and concrete slabs may conceal asbestos;
all these should be included in the health and safety plan required under the Construction (Design and Management) Regulations 1994. If suspected asbestos materials are encountered during the demolition, work should be halted immediately and the asbestos risk assessment reviewed.
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Survey planning.
Prior to any survey taking place the followings steps should be followed:-
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Preliminary site meeting held to understand health and safety requirements at the site. The survey plan must also be agreed and both parties must establish who supplies what resources in order to carry out the survey. Also the time scale must be agreed and access to restricted areas granted. A walk-through of the buildings in question is also imperative to familiarise the surveyor with
the premises.
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A basic desk to study is advisable whereby the surveyor can establish, from drawings etc, his or her requirements for the survey.
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Survey parameters must be established e.g. exactly what the client expects the survey report to contain (for example friability, content, surface treatment, condition, location, accessibility, etc) and calculation of risk.
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What is an asbestos register?
The term register has been widely used by premises' managers and consultants to describe a record of a particular feature. An asbestos register is therefore a record of materials containing asbestos. In its most basic form a register may simply be a note
on a drawing showing that asbestos based ceiling tiles have been identified within an office area. A more sophisticated record would include information on the type of asbestos and the extent and condition of the tiles.
At the moment there are no set criteria or procedures for creating an asbestos register. A register may be stand alone record, or incorporated into a company's health and safety manual. The important features of a register
is that it provides information on the location of asbestos, or suspected
asbestos materials within a site, and that this information is readily available to those who need it , for example, maintenance workers and contractors.
The Health and Safety at Work etc Act 1974 places responsibilities on employers, employees and the self employed with regard to reducing work related health risks. Asbestos materials should be considered as a potential risk and a knowledge and record of their existence is a first step in managing that risk.
An individual with some experience of the site or building structure is ideally suited for management of the register. For larger sites in-house facility management teams or external consultants may be
appropriate. Either way the person(s) responsible for the register will be expected to carry out the following
duties:-
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Arrange to encapsulate or remove asbestos where necessary.
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Set up a monitoring programme to ensure that in-situ asbestos is monitored,
and removed or encapsulated if damaged.
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Ensure that a suitably licensed contractor is used for any remedial works.
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The site health and safety plan should include the names of those responsible for providing contractors with copies of the site asbestos register prior to contractors commencing works on site.
The asbestos register must be routinely checked and updated at regular intervals by the nominated person(s), and circulated to management and staff accordingly. |
The contents of this page was compiled by John Grummitt.
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