Asbestos

In its natural state asbestos is a fibrous element. When processed for industrial applications it is in powdered form, sheet form, or rolls. It is usually white or light grey in colour. When used in clutches or brake linings, it is often mixed with other elements to give it durability and may have a woven or patterned texture. As a binder in paint, shingles, or linoleum, it is not easily distinguishable from the parent material, but cutting or scraping may reveal small strands or fibers that resemble hair. As it wears down, or is crushed from repeated use, it becomes friable (easily crushed or ground into tiny particles) and it is at that point that particles can become air borne and extremely dangerous. Microscopic pieces can lodge in the pleural sacs around a person's lungs, and once they scar over, the heart must work extra hard to exchange oxygen. In extreme cases, lung cancer or chronic heart problems will result. With this potential to cause respiratory problems, it is essential that all precautions be followed when working with this material. The safest way to work with asbestos is containment and isolation.

Small Asbestos Jobs

When small amounts of asbestos are being removed, or even disturbed to inspect machinery, work can be done safely by keeping the asbestos wet at all times. Spray bottles of water can be used to prevent fibers from becoming airborne.  When work is completed it is important to clean up the "slurry" that was created and to seal up the area and repaint it to make sure no fibers escape.

Some shipyards have asbestos stripping areas where asbestos can be removed safely while it is underwater in large work tanks. These types of areas allow valves, small pipes, and other fittings to be removed from the ship and then stripped of their insulation in a controlled environment. Under these conditions the worker is never exposed to the fibers. All solid waste generated during this type of activity must still be marked "ASBESTOS" and disposed of as hazardous material.

The removal of gasket material from mechanical items, such as valves, exhaust manifolds, or pipe flanges can be hazardous because remnants of asbestos can be indistinguishable from other materials.  It can be inadvertently scraped from surfaces right into the workplace or worse, it is removed using an electric or air powered grinder that creates asbestos dust. This type of treatment will immediately contaminate the area and the workers' clothes. Removing gaskets in this fashion should never be done. If surfaces like this have to be cleaned onboard the ship, they can be soaked with water or even products such as WD-40, and then the broken, fluid saturated pieces can be caught in a plastic bag for proper disposed. Tools and machine surfaces should be wiped down on completion of work, and all rags and consumable materials treated as asbestos waste.

The key point being made here is that if a worker can wet and contain the asbestos, there is minimal chance they will inhale anything dangerous. Even on small jobs however, respirators with the appropriate canister(s) should be used as a precaution, and disposable coveralls also used to minimize the chance of contamination. Other workers in the immediate area should be made aware of the asbestos removal so they do not inadvertently come into contact with the material.

Large Asbestos Jobs

Large asbestos stripping jobs will shut down a space or compartment and preclude any other work fromtaking place without suitable protection. Situations where this may occur are in oler boiler rooms, engine room, or machinery spaces where asbestos was the predominant material used as insulation. Asbestos can also be found in newer vessels, particularly on diesel or turbine exhaust ducting where intense heat needs to be controlled. Some paints and non-skid deck coverings may contain asbestos as its fibrous composition makes it an excellent binder.

When machinery spaces need to be stripped of asbestos, there must be careful planning. Before work starts, all ventilation in the affected area must be sealed off to stop the ingress of asbestos dust. The same must be done for any electrical components or equipment that could trap asbestos.

The work area can be contained by surrounding the worksite with heavy plastic. Duct tape is used to seal up all the seams, with holes cut to accomodate temporary ventilation lines. Ventilation with proper high efficiency particle absorption (HEPA) filters must be used to extract air and contaminants from the work area.

Workers may be signed into and out of the area for safety reasons, and there may even be a monitor assigned to assist with cleanup and to "fetch" tools that may have been forgotten. If the size of the job is huge and the process disturbs an excessive amount of asbestos, whole compartments can become out of bounds.

Showers

Companies will vary on how they approach clean up after an asbestos job.  Some companies will provide a second set of work clothes that can be changed into prior to entering the contaminated area. Upon leaving, the employees will use an air extraction system to remove excess dust from these clothes and then change into clean clothes. Other companies may set up showers and provide disposable coveralls, hoods, gloves, and "booties" to go over the employee's work boots. If showers are provided, workers can change into disposable gear and as they leave, shower, and then change back into their work clothes.  Showers remove any dust caught on a worker, and are also "nice to have" after spending hours inside an air-tight set of disposable coveralls. Some employees have been known to lose up to 10 pounds on completion of a shift requiring heavy physical labour, so proper hydration is important.

Asbestos Waste Disposal and Cleanup

As work progresses, all large pieces of waste should be bagged for disposal and the dusty areas cleaned with asbestos certified vacuums. Special machines with asbestos filters are used to extract the contaminated air so that it is not released into the atmosphere. Air from these types of strip-outs is captured and contained and then the filters disposed of as haz-mat. If showers are not provided, proper change areas with a "clean" zone should be set up. All of the large pieces of asbestos, the disposable coveralls, and any other non-reusable gear that may have been contaminated should be bagged and then properly disposed of under municipal legislation.

Once the strip-out work is completed in large areas such as an entire machinery space, it may be necessary to wash down the entire area with hoses to get all the dust trapped in the machinery castings and on structural beams, longitudinals, or stringers. The water/slurry will be pumped ashore and disposed of as asbestos waste. Some facilities will evaporate the water off this waste before sending it to the landfill, as costs are set by weight.

Smaller areas will then need to be vacuumed and wiped with wet cloths to remove all traces of asbestos. The area must be certified as asbestos-free before employees can work without respirators. The plastic shrouds and enclosures used to contain the dust are usually taken down at the very end of the work, after the wash-down. If they are suspected to contain fibers, they will be disposed of as haz-mat.  If they are clean and fiber-free, they may just go into the garbage or re- used for other work.

There should be no short cuts when working with this type of product.