Washington Administrative Code › Title 296 - Labor and Industries, Department of › Chapter 296-20 - Medical aid rules › IMPAIRMENT RATING › Section 296-20-370 - Respiratory impairments

Current through Register Vol. 24-14, July 15, 2024
(1) Rules for
				evaluation of permanent respiratory impairments:
(a) Definitions.
(i) "FEV1" means the forced expiratory volume
				in 1 second as measured by a spirometric test performed as described in the
				most current
American Thoracic Society Statement on Standardization of
				Spirometry
, and using equipment, methods of calibration, and
				techniques that meet American Thoracic Society (ATS) criteria including
				reproducibility. The measurement used must be taken from a spirogram which is
				technically acceptable and represents the patient's best effort. The
				measurement is to be expressed as both an absolute value and as a percentage of
				the predicted value. The predicted values are those listed in the most current
				edition of the
American Medical Association (AMA) Guidelines
for rating permanent respiratory impairment.
(ii) "FVC" means the forced vital capacity as
				measured by a spirometric test in accordance with criteria described in (a)(i)
				of this subsection.
(iii)
				"FEV1/FVC" is a ratio calculated based on the ATS Guides criteria as described
				in the most current
American Thoracic Society Statement on
				Standardization of Spirometry
.
(iv) "Significant improvement" means a
				fifteen percent or greater improvement in FEV1 (volume) after a
				post-bronchodilator pulmonary function test.
(v) "DLCO" means the diffusion capacity of
				carbon monoxide as measured by a test based on predicted values demonstrated to
				be appropriate to the techniques and equipment of the laboratory performing the
				test according to current ATS standards. DLCO may be considered for impairment
				rating only if accompanied by evidence of impaired gas exchange based on
				exercise testing.
(vi) "VO2 Max"
				means the directly measured oxygen consumption at maximum exercise capacity of
				an individual as measured by exercise testing and oxygen consumption expressed
				in ml/kilo/min corrected for lean bodyweight. Estimated values from treadmill
				or other exercise tests without direct measurement are not acceptable. The
				factor limiting the exercise must be identified.
(vii) "Preexisting impairment" shall be
				reported as described in WAC
				296-20-220(1)(h).
(viii) "Coexisting" is a disease or injury
				not due to or causally related to the work-related condition that impacts the
				overall respiratory disability.
(ix) "Apportionment" is an estimate of the
				degree of impairment due to the occupational injury/exposure when preexisting
				or coexisting conditions are present.
(x) "Dyspnea" is the subjective complaint of
				shortness of breath. Dyspnea alone must not be used to determine the level of
				respiratory impairment. Dyspnea unexplained by objective signs of impairment or
				spirometry requires more extensive testing (i.e., VO2 Max).
(xi) Copies of the
American Thoracic
				Society Statement on Standardization of Spirometry
and ATS standards
				for measuring DLCO can be obtained by ordering
Pulmonary Function Testing
from The American Thoracic Society,
				1740 Broadway, New York, NY 10019-4374, Attn: ATS Statements. Copies of this
				document are available for review in the section of the office of the medical
				director, department of labor and industries, Tumwater building.
These standards are also available through the following
				  references: "American Thoracic Society Committee on Proficiency Standards for
				  Pulmonary Function Laboratories: Standardization of spirometry-1987 update."
Am Rev Respir Dis
1987; 136:1285-1298. "American Thoracic
				  Society DLCO Standardization Conference: Single breath
				  carbon monoxide diffusing capacity (transfer factor): Recommendations for a
				  standard technique."
Am Rev Respir Dis
1987;
				  136:1299-1307.