What is asbestos?

Asbestos is a generic name given to the fibrous variety of six naturally occurring minerals that have been used in commercial products. Asbestos is made up of fiber bundles.  These bundles, in turn, are composed of extremely long and thin fibers that can be easily separated from one to another.  The bundles have splaying ends and are extremely flexible.          The term “asbestos” is not a mineralogical definition.  It is a commercial designation for mineral products that process high tensile strength, flexibility, resistance to chemical and thermal degradation, and high electrical resistance and that can be woven.

What minerals occur as asbestos?

The minerals that can crystallize as asbestos belong to two groups:  serpentine (chrysotile) and amphibole (crocidolite, amosite, anthophyllite asbestos, tremolite asbestos and actinolite asbestos).  Amphiboles are distinguished from one another by the amount of sodium, calcium, magnesium and iron that they contain. Serpentine and amphibole minerals can have fibrous or nonfibrous structures; the fibrous type is called asbestos.          Asbestiform varieties of several other amphiboles have been identified.  Other minerals are similar to asbestos in their particle shape, but they do not possess the characteristics required to classify them as asbestos (see definition of asbestos above).

Checklist:

Asbestos Asbestos in its several commercial forms has been show to be associated with the development of a variety of disease entities, including asbestosis, bronchogenic carcinoma, mesothelioma and cancer. The disease resulting from asbestos exposure may be progressive, even in the absence of further exposure; the inhaled fibers trapped within the lung continue their biological action. In its severe forms, death results from the inability of the body to obtain enough oxygen or from the heart's failure to pump blood through the scarred lungs. In its advanced stages, asbestos is evident by characteristic manifestations on X-rays, by restrictive pulmonary function or by clinical signs, such as finger clubbing or rales (dry, cracking sounds within the lung). Its most important symptom is dyspnea, or undue shortness of breath. This is a partial checklist of some, but not all, rules to follow when dealing with asbestos hazards, based on 1910.1001 -- Asbestos, Subpart Z, Subpart Title Toxic and Hazardous Substances.

 

  • Monitoring


Is the area properly monitored? You must have air samples representative of the 8-hour TWA and 30-minute short-term exposures of each employee.

Has the employee been notified of monitoring results within 15 working days?

Are asbestos areas which exceed TWA or excursion limits regulated?

Are regulated asbestos-containing areas demarcated?

Is access to asbestos-containing areas limited?

Is each employee entering a regulated area supplied and required to wear a respirator?

Are activities like eating, drinking, smoking, chewing tobacco or gum, or applying make-up prohibited in regulated areas?

Have engineering controls been set to reduce employee exposure to asbestos?

Has a compliance program been written and implemented?

Do lunchrooms and eating areas have a positive pressure, filtered air supply?


Ventilation

  • Are local exhaust ventilation and dust collection systems designed, constructed, installed and maintained in accordance with ANZI Z9.2-1979?

  • Are hand-operated and power-operated tools that produce or release asbestos fibers, like saws, scorers, abrasive wheels and drills, provided with local exhaust ventilation systems?

  • Is asbestos handled, mixed, applied, removed, cut, scored or manipulated in a wet state to prevent airborne fibers?

  • Have the asbestos-containing materials been wetted, enclosed or ventilated to prevent airborne fibers during removal from bags, cartons or other containers in which they have been shipped?

  • If you are using compressed air, are you using it with a ventilation system to capture the dust?

 

Respirators, protective clothing

  • Has each employee been allowed to choose either a tight-fitting, air-purifying respirator or a negative pressure respirator?

  • Are employees allowed to change filter elements whenever an increase in breathing resistance is detected, and is an adequate supply of filters available?

  • Has the employer checked to make sure the respirator used by the employee has the least possible face piece leakage and fits properly?

  • Are fit tests performed every six months after the initial test?

  • Are employees provided with coveralls or other full-body clothing and equipment, like gloves, head and foot coverings, face shields, vented goggles, etc.?

  • Are employees provided with clean change rooms with two separate lockers or storage facilities to prevent contamination of the workers' street clothes?