The Valve,exhalation, cataloged under National Stock Number 4240-01-250-6409, is classified within Federal Supply Class 4240 (Safety and Rescue Equipment) of the Fire Fighting, Rescue, and Safety Equipment group. Government technical data includes 2 specifications, cited from the U.S. Government catalog. 4 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4240-01-250-6409 |
| Item Name | Valve,exhalation |
| FSC / FSG | 4240 / 42 — Safety and Rescue Equipment |
| Status | ACTIVE |
| General Characteristics Item Description | SOLE SOURCE REQUIRED BY STATUTE 6.302 |
| Criticality Code Justification | TEXT |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | Y |
| Reference | Meaning |
|---|---|
| R-693 | 5/9 Secondary reference Dalloz Safety |
| R-693 | 3/9 Design control — primary reference Survivair Corp Sub of Comasec Inc |
| 14900179 | 5/9 Secondary reference Dalloz Safety |
| 14900179 | 5/9 Secondary reference Survivair Corp Sub of Comasec Inc |
NSN 4240-01-250-6409 is a Valve,exhalation, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
1 possible match (shared part number, not a government interchangeability claim): 5315-01-601-7617. Verify interchangeability with system specifications before substitution.
Key specifications for 4240-01-250-6409: General Characteristics Item Description: SOLE SOURCE REQUIRED BY STATUTE 6.302; Criticality Code Justification: TEXT; End Item Identification: WILLSON SAFETY PRODUCTS MODELS 500,1200 AND 1500 RESPIRATORS. 2 specifications are documented in the U.S. Government catalog.
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.