Blood-gas studies are performed to detect an impairment in the process of alveolar gas exchange. This defect will manifest itself primarily as a fall in arterial oxygen tension either at rest or during exercise. No blood-gas study shall be performed if medically contraindicated.

A blood-gas study shall initially be administered at rest and in a sitting position. If the results of the blood-gas test at rest do not satisfy the requirements of Appendix C to this part, an exercise blood-gas test shall be offered to the miner unless medically contraindicated. If an exercise blood-gas test is administered, blood shall be drawn during exercise.

Any report of a blood-gas study submitted in connection with a claim shall specify:

Date and time of test;

Altitude and barometric pressure at which the test was conducted;

Name and DOL claim number of the claimant;

Name of technician;

Name and signature of physician supervising the study;

The recorded values for PC02, P02, and PH, which have been collected simultaneously (specify values at rest and, if performed, during exercise);

Duration and type of exercise;

Pulse rate at the time the blood sample was drawn;

Time between drawing of sample and analysis of sample; and

Whether equipment was calibrated before and after each test.

If one or more blood-gas studies producing results which meet the appropriate table in Appendix C is administered during a hospitalization which ends in the miner's death, then any such study must be accompanied by a physician's report establishing that the test results were produced by a chronic respiratory or pulmonary condition. Failure to produce such a report will prevent reliance on the blood-gas study as evidence that the miner was totally disabled at death. (e) In the case of a deceased miner, where no blood gas tests are in substantial compliance with paragraphs (a), (b), and (c), noncomplying tests may form the basis for a finding if, in the opinion of the adjudication officer, the only available tests demonstrate technically valid results. This provision shall not excuse compliance with the requirements in paragraph (d) for any blood gas study administered during a hospitalization which ends in the miner's death.