FSG: 42 — Fire Fighting, Rescue, and Safety Equipment
General Description
The Mask,chemical-Biological, cataloged under National Stock Number 4240-01-646-2709, is classified within Federal Supply Class 4240 (Safety and Rescue Equipment) of the Fire Fighting, Rescue, and Safety Equipment group. 2 additional reference documents (drawings, advisory and superseded references) are recorded in the U.S. Government catalog. Current acquisition status: Active.
Catalog Facts
Item Name
Mask,chemical-Biological
FSC / FSG
4240 — Safety and Rescue Equipment (FSG 42)
Technical Specifications
Parameter
Value
NSN
4240-01-646-2709
Item Name
Mask,chemical-Biological
FSC / FSG
4240 / 42 — Safety and Rescue Equipment
Status
ACTIVE
Lifecycle & Compliance
Acquisition Status
ACTIVE
DEMIL Code
DEMIL F — Mutilate — Cut
Hazard
Possible hazard — SDS may be required (DLA HMIC P)
Criticality Code
X
Cross-Reference Index
No manufacturer part numbers on file in the U.S. Government catalog.
Reference documents
Reference
Meaning
5-1-4243-40
3/2Design control — primary reference
U.S. Government activity
72053/5
5/9Secondary reference
Avon Protection Systems Incorporated Dba Avon Protection Systems Inc
No interchangeability data on file.
Other items in FSC 4240 — Safety and Rescue Equipment
Items in the same Federal Supply class. No interchangeability or substitution relationship is implied.
4240-00-001-1515
4240-00-001-1515 · Item name not on file
4240-00-001-2684
4240-00-001-2684 · Item name not on file
4240-00-006-0022
HOSE,EVACUATION
4240-00-007-4576
4240-00-007-4576 · Item name not on file
4240-00-007-8182
4240-00-007-8182 · Item name not on file
4240-00-007-8183
4240-00-007-8183 · Item name not on file
4240-00-007-8184
4240-00-007-8184 · Item name not on file
4240-00-007-8185
4240-00-007-8185 · Item name not on file
Frequently Asked Questions
What is NSN 4240-01-646-2709?
NSN 4240-01-646-2709 is a Mask,chemical-Biological, classified under FSC 4240, Safety and Rescue Equipment. Status: active.
Is NSN 4240-01-646-2709 hazardous material?
Possible hazard — SDS may be required (DLA HMIC P). Hazard information on this page is shown exactly as it appears in the DLA record.
What is the DEMIL code for NSN 4240-01-646-2709?
NSN 4240-01-646-2709 has DEMIL Code F. Demilitarization may be required before disposal or transfer to non-military entities.
Sources
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.
✓ Data cited from the U.S. Government catalog; commercial cross-references from OEM and certified industry sources.