An allergic lung reaction to inhaled substances that causes inflammation and may lead to breathing difficulty.
Because the ratings turn almost entirely on pulmonary function test results, the most directly useful records are spirometry reports showing your FVC as a percentage of the predicted value, and DLCO (SB) test reports showing your diffusion capacity as a percentage of predicted. These numbers place you within a specific rating level, so accurate and current test results matter.
For a 100% rating, records showing cor pulmonale or pulmonary hypertension—such as echocardiogram or right-heart catheterization reports—are relevant, as are prescriptions or treatment notes documenting outpatient oxygen therapy. Cardiopulmonary exercise test results showing maximum oxygen consumption below 15 ml/kg/min with cardiorespiratory limitation also support this level.
Statements from you or people who know you describing how breathing difficulty affects your ability to work, walk, climb stairs, or carry out daily tasks can help show the functional impact of your measured lung impairment. Physician notes, hospital records, and pulmonologist reports that document the progression or current severity of your condition round out the picture alongside the objective test findings.
Conditions that are often caused or made worse by this one. If you have any of these, they may be claimable as secondary service connection.
