The Hood,chemical-Biological Mask, cataloged under National Stock Number 4240-01-189-9423, is classified within Federal Supply Class 4240 (Safety and Rescue Equipment) of the Fire Fighting, Rescue, and Safety Equipment group. The manufacturer of record is Mine Safety Appliances Company. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 3 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. 1 item shares a part number with this NSN in the catalog (possible match — not a government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 | 4240-01-189-9423 |
| Primary Part Number | 305022 |
| Item Name | Hood,chemical-Biological Mask |
| FSC / FSG | 4240 / 42 — Safety and Rescue Equipment |
| Manufacturer | Mine Safety Appliances Company |
| Status | ACTIVE |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL F — Mutilate — Cut |
| Hazard | Possible hazard — SDS may be required (DLA HMIC P) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 305022 PRIMARY | Mine Safety Appliances Company (USA) |
| Reference | Meaning |
|---|---|
| 864-55 | 5/9 Secondary reference U.S. Government activity |
| 305022 | 5/9 Secondary reference Eastern Canvas Products Inc |
| 864-55 | 5/9 Secondary reference Avox Systems Inc Dba Avox Systems Inc |
NSN 4240-01-189-9423 is a Hood,chemical-Biological Mask, manufactured by Mine Safety Appliances Company, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
NSN 4240-01-189-9423 has 1 manufacturer part number on file: 305022 (Mine Safety Appliances Company).
1 possible match (shared part number, not a government interchangeability claim): 5895-01-655-5358. Verify interchangeability with system specifications before substitution.
Key specifications for 305022: End Item Identification: MCU-2/P CHEM BIOLOGICAL MASK. 0 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.
NSN 4240-01-189-9423 has DEMIL Code F. Demilitarization may be required before disposal or transfer to non-military entities.
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.