Washington Administrative Code › Title 296 - Labor and Industries, Department of › Chapter 296-62 - General occupational health standards › Part I-1 - ASBESTOS, TREMOLITE, ANTHOPHYLLITE, AND ACTINOLITE › Section 296-62-07749 - Appendix H - Medical surveillance guidelines for asbestos - Nonmandatory

Current through Register Vol. 24-14, July 15, 2024
(1) Route of entry
				inhalation, ingestion.
(2)
				Toxicology.
Clinical evidence of the adverse effects associated with
				  exposure to asbestos is present in the form of several well-conducted
				  epidemiological studies of occupationally exposed workers, family contacts of
				  workers, and persons living near asbestos mines. These studies have shown a
				  definite association between exposure to asbestos and an increased incidence of
				  lung cancer, pleural and peretoneal mesothelioma, gastrointestinal cancer, and
				  asbestosis. The latter is a disabling fibrotic lung disease that is caused only
				  by exposure to asbestos. Exposure to asbestos has also been associated with an
				  increased incidence of esophageal, kidney, laryngeal, pharyngeal, and buccal
				  cavity cancers. As with other known chronic occupational diseases, disease
				  associated with asbestos generally appears about twenty years following the
				  first occurrence of exposure: There are no known acute effects associated with
				  exposure to asbestos.
Epidemiological studies indicate that the risk of lung cancer
				  among exposed workers who smoke cigarettes is greatly increased over the risk
				  of lung cancer among nonexposed smokers or exposed nonsmokers. These studies
				  suggest that cessation of smoking will reduce the risk of lung cancer for a
				  person exposed to asbestos but will not reduce it to the same level of risk as
				  that existing for an exposed worker who has never smoked.
(3) Signs and symptoms of exposure-related
				disease.
The signs and symptoms of lung cancer or gastrointestinal
				  cancer induced by exposure to asbestos are not unique, except that a chest X
				  ray of an exposed patient with lung cancer may show pleural plaques, pleural
				  calcification, or pleural fibrosis. Symptoms characteristic of mesothelioma
				  include shortness of breath, pain in the walls of the chest, or abdominal pain.
				  Mesothelioma has a much longer latency period compared with lung cancer (forty
				  years versus fifteen to twenty years), and mesothelioma is therefore more
				  likely to be found among workers who were first exposed to asbestos at an early
				  age. Mesothelioma is always fatal.
Asbestosis is pulmonary fibrosis caused by the accumulation
				  of asbestos fibers in the lungs. Symptoms include shortness of breath,
				  coughing, fatigue, and vague feelings of sickness. When the fibrosis worsens,
				  shortness of breath occurs even at rest. The diagnosis of asbestosis is based
				  on a history of exposure to asbestos, the presence of characteristic radiologic
				  changes, endinspiratory crackles (rales), and other clinical features of
				  fibrosing lung disease. Pleural plaques and thickening are observed on X rays
				  taken during the early stages of the disease. Asbestosis is often a progressive
				  disease even in the absence of continued exposure, although this appears to be
				  a highly individualized characteristic. In severe cases, death may be caused by
				  respiratory or cardiac failure.
(4) Surveillance and preventive
				considerations.
As noted above, exposure to asbestos has been linked to an
				  increased risk of lung cancer, mesothelioma, gastrointestinal cancer, and
				  asbestosis among occupationally exposed workers. Adequate screening tests to
				  determine an employee's potential for developing serious chronic diseases, such
				  as cancer, from exposure to asbestos do not presently exist. However, some
				  tests, particularly chest X rays and pulmonary function tests, may indicate
				  that an employee has been overexposed to asbestos increasing his or her risk of
				  developing exposure-related chronic diseases. It is important for the physician
				  to become familiar with the operating conditions in which occupational exposure
				  to asbestos is likely to occur. This is particularly important in evaluating
				  medical and work histories and in conducting physical examinations. When an
				  active employee has been identified as having been overexposed to asbestos
				  measures taken by the employer to eliminate or mitigate further exposure should
				  also lower the risk of serious long-term consequences.
The employer is required to institute a medical surveillance
				  program for all employees who are or will be exposed to asbestos at or above
				  the permissible exposure limits (0.1 fiber per cubic centimeter of air) for
				  thirty or more days per year and for all employees who are assigned to wear a
				  negative pressure respirator. All examinations and procedures must be performed
				  by or under the supervision of a licensed physician, at a reasonable time and
				  place, and at no cost to the employee.
Although broad latitude is given to the physician in
				  prescribing specific tests to be included in the medical surveillance program,
				  WISHA requires inclusion of the following elements in the routine
				  examination:
(a) Medical and work
				histories with special emphasis directed to symptoms of the respiratory system,
				cardiovascular system, and digestive tract.
(b) Completion of the respiratory disease
				questionnaire contained in WAC
				296-62-07741, Appendix
				D.
(c) A physical examination
				including a chest roentgenogram and pulmonary function test that includes
				measurement of the employee's forced vital capacity (FVC) and forced expiratory
				volume at one second (FEV1).
(d) Any laboratory or other test that the
				examining physician deems by sound medical practice to be necessary.
The employer is required to make the prescribed tests
				  available at least annually to those employees covered; more often than
				  specified if recommended by the examining physician; and upon termination of
				  employment.
The employer is required to provide the physician with the
				  following information: A copy of this standard and appendices; a description of
				  the employee's duties as they relate to asbestos exposure; the employee's
				  representative level of exposure to asbestos; a description of any personal
				  protective and respiratory equipment used; and information from previous
				  medical examinations of the affected employee that is not otherwise available
				  to the physician. Making this information available to the physician will aid
				  in the evaluation of the employee's health in relation to assigned duties and
				  fitness to wear personal protective equipment, if required.
The employer is required to obtain a written opinion from the
				  examining physician containing the results of the medical examination; the
				  physician's opinion as to whether the employee has any detected medical
				  conditions that would place the employee at an increased risk of
				  exposure-related disease; any recommended limitations on the employee or on the
				  use of personal protective equipment; and a statement that the employee has
				  been informed by the physician of the results of the medical examination and of
				  any medical conditions related to asbestos exposure that require further
				  explanation or treatment. This written opinion must not reveal specific
				  findings or diagnoses unrelated to exposure to asbestos and a copy of the
				  opinion must be provided to the affected employee.