Diagnostic Code 6834 · 38 CFR §4.97
Silicosis is a permanent, progressive lung disease caused by inhaling fine crystalline silica dust. The dust particles lodge in the alveoli, trigger a chronic inflammatory response, and over years produce nodular scarring that stiffens the lungs and reduces their ability to transfer oxygen. Symptoms creep in slowly — shortness of breath on exertion that gets worse year over year, dry cough, chest tightness, fatigue — and the disease often is not diagnosed until imaging is done for another reason. Veterans at elevated risk include combat engineers, demolition specialists, sandblasters, military masons and construction trades, vehicle and aircraft maintainers who worked with abrasive blasting, and infantry exposed to repeated dust storms or improvised explosive device debris. Silicosis is rated under DC 6834 within the General Rating Formula for Interstitial Lung Disease in 38 CFR §4.97, the same PFT-driven framework used for asbestosis and other dust diseases of the lung.
| Rating | Criteria |
|---|---|
| 10% | FEV-1 of 71 to 80 percent of predicted, OR FEV-1/FVC ratio of 71 to 80 percent, OR DLCO (SB) of 66 to 80 percent of predicted. |
| 30% | FEV-1 of 56 to 70 percent of predicted, OR FEV-1/FVC ratio of 56 to 70 percent, OR DLCO (SB) of 56 to 65 percent of predicted. |
| 60% | FEV-1 of 40 to 55 percent of predicted, OR FEV-1/FVC ratio of 40 to 55 percent, OR DLCO (SB) of 40 to 55 percent of predicted, OR maximum exercise capacity of 15 to 20 ml/kg/min of oxygen consumption with cardiorespiratory limitation. |
| 100% | FEV-1 less than 40 percent of predicted, OR FEV-1/FVC less than 40 percent, OR DLCO (SB) less than 40 percent of predicted, OR maximum exercise capacity less than 15 ml/kg/min of oxygen consumption with cardiorespiratory limitation, OR cor pulmonale (right-sided heart enlargement), OR pulmonary hypertension shown by echocardiogram or cardiac catheterization, OR need for continuous outpatient oxygen therapy. |
A high-resolution CT scan of the chest is the most useful imaging — it shows the characteristic small nodular opacities, often concentrated in the upper lobes, and any progressive massive fibrosis if the disease has advanced. Pulmonary function tests with spirometry, lung volumes, and a DLCO measurement establish the rating tier directly. A six-minute walk test or formal cardiopulmonary exercise testing supports the higher tiers when symptoms outpace what the PFT numbers show alone. Occupational history from service treatment records, DD-214 MOS history, command-statement records of dust exposure, and lay statements from fellow service members describing the exposure events all build the nexus. A pulmonologist diagnosis differentiating silicosis from other dust diseases and ruling out competing causes closes the case.
Silicosis from deployment is recognized when the exposure history involves work with crystalline silica — sandblasting, demolition, masonry, blast-pit operations, vehicle maintenance with abrasive media — or extreme repeated exposure to silica-rich desert dust over a sustained period. The disease typically takes years to develop, so a current diagnosis in a post-deployment veteran is consistent with exposure during service even when the symptoms first appeared after separation. A pulmonologist nexus opinion connecting the exposure pattern to the current imaging and PFT findings is the key piece of evidence.
Both are dust diseases that produce interstitial scarring, both are rated under DC 6834 and DC 6833 respectively, and the rating criteria are identical PFT-based tiers. The differences are in the imaging pattern (silicosis tends to show small upper-lobe nodules, asbestosis shows lower-lobe interstitial markings with pleural plaques), the time course (silicosis can progress for decades after exposure stops), and the secondary risks (silicosis raises TB and lung cancer risk; asbestosis raises mesothelioma risk). A high-resolution CT and pulmonologist read distinguishes them.
Silicosis is a progressive, irreversible scarring disease — PFT numbers do not typically improve. They can fluctuate slightly with effort and technique, but the underlying lung fibrosis does not reverse. A short-term improvement is not a basis for rating reduction under 38 CFR §3.344. If a re-evaluation produces a temporarily better number, the protection rules generally prevent a reduction unless the improvement is sustained and material.