The Valve,safety Relief, cataloged under National Stock Number 4820-01-446-1666, is classified within Federal Supply Class 4820 (Valves, Nonpowered) of the Valves group. Government technical data includes 3 specifications, cited from the U.S. Government catalog. 1 additional reference document (drawings, advisory and superseded references) is recorded in the U.S. Government catalog. Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 4820-01-446-1666 |
| Item Name | Valve,safety Relief |
| FSC / FSG | 4820 / 48 — Valves, Nonpowered |
| Status | ACTIVE |
| Nominal Thread Size | 0.500 INCHES ALL ENDS IN |
| Thread Series Designator | NPT ALL ENDS |
| Opening Pressure Setting | 100.0 POUNDS PER SQUARE INCH LBS |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL A — No Demilitarization Required |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Reference | Meaning |
|---|---|
| 99136 | 3/2 Design control — primary reference U.S. Government activity |
NSN 4820-01-446-1666 is a Valve,safety Relief, classified under FSC 4820, Valves, Nonpowered. Status: active.
Key specifications for 4820-01-446-1666: Nominal Thread Size: 0.500 INCHES ALL ENDS IN; Part Name Assigned by Controlling Agency: SAFETY VALVE; End Item Identification: NIMITZ CLASS CVN; Thread Series Designator: NPT ALL ENDS. 3 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). 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.