Asbestos is a set of six naturally occurring silicate minerals used commercially for their desirable physical properties. They all have in common their eponymous, asbestiform habit: long (ca. 1:20 aspect ratio), thin fibrous crystals. The prolonged inhalation of asbestos fibers can cause serious illnesses including malignant lung cancer, mesothelioma, and asbestosis (a type of pneumoconiosis). The European Union has banned all use of asbestos and extraction, manufacture and processing of asbestos products.
Asbestos became increasingly popular among manufacturers and builders in the late 19th century because of its sound absorption, average tensile strength, its resistance to fire, heat, electrical and chemical damage, and affordability. It was used in such applications as electrical insulation for hotplate wiring and in building insulation. When asbestos is used for its resistance to fire or heat, the fibers are often mixed with cement (resulting in fiber cement) or woven into fabric or mats.
Asbestos mining began more than 4,000 years ago, but didn’t start large-scale until the end of the 19th century. The world’s asbestos mining peaked around 1975, when asbestos was being mined in some 25 countries, but is today less than half of what it was in the mid-1970s.
Asbestos is a mineral fibre (silicates) with a variety of uses dependent on length, texture and composition.
Asbestos – white – solid white fibers insoluble in water. Used in paper products, floor tiling, roofing felts, boards, insulation, brake linings.
Asbestos – brown – solid brown fibers, insoluble in water, used in textiles and found in mixtures of asbestos. Asbestos – blue – solid, insoluble in water. Not used in UK since 1970.
Asbestos is an active carcinogen and can give rise to serious respiratory troubles. Protective clothing and respirators should be worn during processing, drying or grinding and indeed whilst carrying out onboard surveys or entering containers. Parts of the body which may have been exposed to the material should be immediately and thoroughly washed . Will become caked and discoloured by wetting but can be reconditioned by drying and by thorough washing if affected by sea water, which processes may result in a weight loss.
A fibrous white or grey mineral product which is incombustible and stows well with the finer cargoes. When shipped in sheets packed in crates, stow on edge and avoid any weight above. Asbestos is the common name given to a number of naturally occurring inorganic silicates with complex compositions and of fibrous crystaline structure. There are four main types:
1. Chrysotilc (known as white asbestos) is the commonest type. It is a fine silky flexible white to grey/green fibre.
2. Amosite (known as brown asbestos) is a straight brittle fibre light to grey to pale brown.
3. Crocidolite (known as blue asbestos) is generally accepted as being the most harmful type of asbestos. It is a straight flexible blue fibre.
4. Anthophyllite. It is a brittle, white to brown fibre.
Main uses are/were in the manufacture of fire-proof fabrics, brake linings, electrical and heat insulation, building materials when compounded with cement, and chemical filters.
Shipment / Storage
The European Union has banned all use of asbestos and extraction, manufacture and processing of asbestos products.
Asbestos fibre of all types should be securely packed in impermeable bags. If deliveries are made up in tounitised loads these should be securely fastened and may be further enclosed in a cover of impermeable material, properly secured. If ISO containers are used the shipper should ensure that all projections inside the container are removed or adequately shielded to avoid damage to the bags in transit. Ideally should be loaded on last in, first out basis. Stow well away from foodstuffs. Hooks or other sharp equipment should not be used. Respirators of an approved type should be worn by those engaged in the collection and re-bagging of any loose materials. Suitable protective clothing should be worn and arrangements made for its cleaning and storage after use. Damaged bags should be over slipped as soon as possible into suitable impermeable bags, a supply of which should be available where asbestos consignments are being handled. The bags should be securely tied, clearly identified and forwarded with the consignment. Any remaining spilled material should be finally cleared either by vacuum equipment or by thoroughly wetting and sweeping. All spillage should be collected and disposed of in accordance with local regulations. Other transport including ISO containers used for the carriage of asbestos may become contaminated by asbestos. It is recommended that these containers be thoroughly cleaned by means of an approved vacuum cleaner after discharging each load. Asbestos, and asbestos products, any be considered Dangerous Goods, if they are likely to release significant quantities of asbestos. Such products would require control under the asbestos entry in class 9 of the IMDG Code. These would include raw asbestos, treated asbestos (still in the form of free fibres) and furniture, cushions, etc., stuffed with asbestos. Non-hazardous products would be cement/asbestos sheet or pipe, brake shoes and furniture where the asbestos is unlikely to escape as free fibres, e.g. when used as a toughening agent in structural plastics rather like glass fibres. If in any doubt as to the classification the product should be submitted to the appropriate Authority.
Cargo spaces or freight containers that have contained any type of Asbestos should be carefully cleaned prior to further use and / or repair / maintenance work. All waste material should be collected in impermeable and sealed bags for disposal ashore. Inhalation of dust particles is dangerous (lung diseases). Although asbestos itself will not burn, it easily absorbs oil and may consequently reach ignition.
Unprotected exposure to asbestos dust may produce a risk of severe injury to the respiratory system if inhaled.
Reference is made to the relevant IMO publications of hazardous cargo.