Asbestos Awareness. - For Everybody. Course Notes. January Carl Wales Health and Safety Advisor Fenlock Hansen Ltd.

Transcription

1 Asbestos Awareness - For Everybody Course Notes Carl Wales Health and Safety Advisor Fenlock Hansen Ltd January 2004 Asbestos Awareness For Everybody: Version 1 Page 1 of 15

2 Contents 1. Introduction 2. Health Effects 3. Identifying Asbestos 4. Action upon Discovery Asbestos Awareness For Everybody: Version 1 Page 2 of 15

3 Introduction In its natural state, asbestos is an opencast-mined rock. The rock is crushed to release fibres, which are added to a number of other materials. In order to take advantage of its beneficial properties, that gave it the name of the Miracle Mineral. First known asbestos mine 1BC, Evvoia, in Greece. 2000BC first reference Asbestos is a natural mineral (silicates of Magnesium, Sodium, calcium, Iron and Aluminium). The name asbestos is derived from the Greek meaning inextinguishable. Mined on a commercial scale in the USA from 1900 Currently in 3000 materials Estimated to be present in 74.5% of all commercial buildings. Now, mining of asbestos in virtually non-existent. However, the inclusion of asbestos in such a large number of building products has made it one of the most widespread contaminants on earth. Asbestos Awareness For Everybody: Version 1 Page 3 of 15

4 One Product - Two Families Amphiboles Have hook-like fibres that lodge into body tissue. Least common, but the most hazardous. Have a Fibrogenic reaction with skin tissue, causing abnormal cell growth, leading to cancer. Out of the two main amphiboles, Crocidolite is the most toxic but fortunately, findings are very rare. Types Amosite (Brown) Crocidolite (Blue) Anthophyllite Actinolite Tremolite Serpentines Identified by their snake like fibre. The least toxic of all the fibres. Chrysotile is the most common and is the estimated cause of 95% of all asbestos related disease. Types Chrysotile (White) Asbestos Awareness For Everybody: Version 1 Page 4 of 15

5 Properties Low Thermal Conductivity - will not conduct heat easily, extreme heat that will affect most building materials will have little effect on the asbestos fibres giving it a high temperature resistance. Because of its low thermal conductivity it was often used on swimming pool and drying shed roofs to prevent condensation and around steel structures to prevent it buckling in a fire High Tensile Strength - the fibres are virtually impossible to break, therefore it was used to reinforce materials. Low Electrical Conductivity - used as a good electrical insulator. Chemically Inert a long lasting product that does not degrade. Size - Because the fibres are so small and versatile, it can be applied to anything and in any state i.e. boards, spray coatings A product with all the above properties has limitless uses however. Proliferation During World War II, the fire authorities identified that building fires were not contained in the premises where the fire started. In panic, fireproof materials were installed into new buildings to help isolate the fires. The cheapest and most effective products contained the miracle mineral - asbestos. During the war, imports were obviously restricted and demand far out weighed supply. Imports were at their highest Asbestos Awareness For Everybody: Version 1 Page 5 of 15

6 Health Effects Background In 1885, a mine s occupational health nurse identified that miners working in some mines had a greater rate of serous respiratory problems, in comparison to miners working in another mines. She identified the cause as the minerals that were present in the mines where respiratory illnesses were most common. These minerals were silicates of Magnesium, Sodium, Calcium, Iron, and Aluminium Asbestos! It was identified that nearly a third of all people who regularly work with asbestos suffer a terminal illness; the UK starts to import enormous amounts Results from the research into the effects of asbestos (started in 1936) are published, identifying that there was no link between asbestos and a reduced lung function Correct results from the 1936 research are finally published due to excessive public pressure resulting from Toxicological studies in Sixty-six years and millions of tonnes later its use is finally prohibited. Asbestos Awareness For Everybody: Version 1 Page 6 of 15

7 Diseases Fibres - Properties Inhalable > 7microns in diameter, most will be rejected by the bodies defence systems i.e. hairs, mucus. Respirable < 7microns in diameter, will bypass these systems and settle deep inside the lungs. High Tensile Strength Very strong fibre, which cannot be broken down by the body. Chemically Inert Resistant to being broken down by chemicals. As the fibres are so small, it makes it easy for them to get into the body and straight to the internal organs, causing damage. Due to the fibres high tensile strength and chemical inertia, once the fibres are inside the body, the body can t break them down in order to prevent further damage. The fibres are able to cause a reaction with skin tissue, resulting in growths. The reaction is known as fibrogenic and the agent causing the reaction, in this case, asbestos fibres, is referred to as a carcinogen. Asbestos Awareness For Everybody: Version 1 Page 7 of 15

8 Asbestosis The fibres scar the lung tissue, reducing their flexibility and hence the volume of air they can be inhaled and absorb into the blood. Treatment is to remove from the source of exposure, but this will only reduce the rate of the disease, not stop it. The heart will come under too much strain, and eventually fail, in its attempt to get oxygen around the body. Direct correlation with exposure to fibres and the rate at which asbestosis is contracted. First official case identified in 1900 Asbestosis Reduced lung capacity 10 years + to develop. Treatment will slow down but not halt. Often result in death through heart problems. Approx 300 deaths P.A, and decreasing Hansen Managing Safely Asbestos Awareness For Everybody: Version 1 Page 8 of 15

9 Lung Cancer Carcinogenic fibres cause the Fibrogenic reaction with lung tissue, eventually suffocating the lung. Treatment will be Chemotherapy or Radiotherapy Synergistic effect- the likelihood of contracting lung cancer if you are a smoker and are exposed to asbestos fibres will multiple, estimates are varied some say the likelihood will increase by a multiple of 4, other estimates say a multiple of 50 Cancers of the throat, nose, trachea, digestive tract, and stomach are also common from exposure to fibres. First official case identified in 1947 Lung Cancer Similar to Tobacco L.C. Operable in very early stages. Appears years + after first exposure. 90% die within 5 years. Approx 2500 deaths P.A Hansen Managing Safely Asbestos Awareness For Everybody: Version 1 Page 9 of 15

10 Mesothelioma Cancerous growth on the pleura (sack that surrounds the lungs). The growth grows between the lungs and the rib cage, pressing against the rib cage, crushing the lungs whilst it is growing. In some rare cases, the disease has been contracted at an accelerated rate, with the victims contracting the disease within 10 years of exposure. The group of workers at greatest risk are maintenance and demolition workers Now the greatest ill-health worry linked to asbestos. Latest estimates for deaths: Will increase by a multiple of 2 or 3 Account for 1% of all male deaths 10,000 per year 200 per week. Deaths will double by 2020 First official case 1959 Mesothelioma Extremely painful death up to 50 years after exposure deaths P.A. Life expectancy 9 18 months. Hansen Managing Safely Asbestos Awareness For Everybody: Version 1 Page 10 of 15

11 Identifying Asbestos Materials, which contain asbestos, are referred to as ACMs Asbestos Containing Materials. All buildings built or maintained between 1950 and 1985 have a high probability of containing asbestos, although it is known to have been used in the years after the ban. Spray Applications Spray applications contain about 85% asbestos, a mixture of Chrysotile (white), Amosite (brown) and Crocidolite (blue). Common uses are Thermal and Acoustic insulation, and to prevent condensation. Sprayed onto structural steel work to prevent it from buckling in a fire. Sprayed onto walls and ceilings and inside machinery bodies as sound insulation Sprayed onto swimming pool and drying shed ceilings to prevent condensation. Lagging Applied as a paste, smoothed off and left to dry, contains 90% asbestos, usually a mixture of Chrysotile (white), Amosite (brown), and Crocidolite (blue). Common Uses are as a Thermal Insulator Lagging hot water pipes Lagging boilers Used as a seal around pipes where they pass through walls. Insulating Board One of the most commonly used asbestos containing materials in the construction industry. Contains between 20 and 40% Amosite (brown) but can also have traces of the other two. Common uses are as a thermal, electrical and acoustic insulator and as a fire stop. Boxing in pipes Partition walls Asbestos Awareness For Everybody: Version 1 Page 11 of 15

12 Fire stop between rooms and buildings (especially in the roof and floor space) Ceilings Backs and inside fire doors Beading on fire screens Linings to electrical cupboards Linings to boiler cupboards Used as ceiling tiles Linings to lift shafts (friction) Gasket Applied as a wet or dry seal. Usually 70% Chrysotile (white) usually with a small quantity of Crocidolite (blue). Common uses as a heat insulator Seal in between metal joints Used to plug holes e.g. were pipes pass through walls. Rope up to 100% Chrysotile (white), Common Uses used as a gasket or a seal Kiln / Oven doors Chimney seals Fuse Boards Paper up to 100% Chrysotile (white) Common uses are as a thermal, electrical and acoustic insulator. Linings of machinery Textiles up to 100% Chrysotile (white) Common uses are as a thermal insulator. Asbestos Awareness For Everybody: Version 1 Page 12 of 15

13 Fire Blankets Curtains Clothing Floor Tiles Newer type (usually up to 9 square) 7-10% Chrysotile (white), Older type (usually 12 square) 20% Chrysotile (white) Moulded Plastic Asbestos was used to re-enforce plastic, contains 50 70% Chrysotile (white) Common uses are Window Cills Toilet seats and cisterns Water tanks Cement Products Between 10 and 15% Chrysotile (white). Common uses as a thermal insulator and as a weather resistant product Roof and wall sheeting Cladding Tiles Gutters and down pipes Soffit and facia Lining of fire doors. Other asbestos containing materials include Artex, putty, silicon, glazing beads, mail bags, surgical thread, cigarette tips, tea pots, cups, artificial snow and toothpaste. Asbestos Awareness For Everybody: Version 1 Page 13 of 15

14 Action Upon Discovery Action upon Discovery Stop Work immediately Restrict access Decontaminate/ shower Inform Minimise Fibre release Arrange for sampling Never take a chance it may contain asbestos. Hansen Managing Safely From the end of May 2004 it will be a legal requirement for the owner / occupiers of building to have an asbestos register. This will identify were asbestos is located the type of asbestos and the condition that it is in. Asbestos is only dangerous when it is released in to the air. If asbestos is kept encapsulated in its original state it is harmless, it is only a health hazards if there is a possibility of fibre release. Hansen Procedures on identifying a suspected asbestos containing material Stop work immediately and remove yourself from the area. Inform other persons in the work area of your suspicions. Isolate the area e.g. close / lock the door and erect a warning sign. Inform Hansen and the principle contractor s site management, they will inform the client and the health and safety department. Do not restart until sampling has been completed NOTE we do not remove A.C.M as a rule. Some A.C.Ms can be removed without the use of a licensed contractor but the Health and Safety Department MUST be informed and authorise the Safe Working Practice that is issued for the completion of the work. Asbestos Awareness For Everybody: Version 1 Page 14 of 15

15 PPE Hansen Managing Safely Personnel Protective equipment to be worn for the removal of asbestos Disposable all in one overall with elasticated hood, coughs and legs. FFP3 respiratory protection (hood must cover straps) Safety footwear (without laces) Take overalls off inside out Then remove R.P.E Wash hands thoroughly The HSE guidance issued with this presentation shows guidance on safe working practices, suitable PPE, and what Asbestos Containing Materials can and can not be removed by a unlicensed contractor. Asbestos Awareness For Everybody: Version 1 Page 15 of 15