A glove that has passed its protective limit looks almost exactly like one that has not. Barrier failure is silent: the wearer receives no warning when a pin-hole or a saturated elastomer lets agent through. Most organisations can inspect a glove. Fewer can answer a simple audit question: why is this pair still in the bag? The difference between the two is not diligence in the field but criteria written down before issue.
Three clocks, not one
End-of-life is decided by three independent clocks. The first is calendar time: shelf life in sealed packaging, then service life counted from first issue. The second is cumulative duty: hours in the hot zone, number of entries, number of decontamination cycles. The third is events: a known agent contact, an unidentified liquid, a mechanical breach, a storage failure.
Whichever clock runs out first governs. Procurement teams usually track only the first, because it is printed on the carton; the other two live in unit logs that are often incomplete. Deciding at contract stage which clocks the supplier will support matters more than any single specification value.
What the barrier is, and where it ends
CBRN protective gloves cover two threat families: chemical warfare agents and toxic industrial chemicals on one side, biological and radiological particulates on the other. Materials map onto that split. Butyl and halogenated butyl offer low permeability to many agents while staying flexible in the cold. Fluoroelastomers resist fuels, solvents and oxidisers that attack butyl. Multilayer film laminates combine polar and non-polar barriers, but their weakest point is often the tie layer between them. In supported gloves the liner can wick liquid from a fingertip pin-hole to the whole hand, so the assembly, not the film, is what gets tested.
Ratings describe a material sample, not a lifespan. EN ISO 374-1 Type A, B or C grades performance against lettered chemicals, EN ISO 374-5 addresses micro-organisms and viruses, and ASTM F739 or ISO 6529 produce the breakthrough numbers behind those claims. None of them states how many missions a pair survives.
Tiering the criteria to the role
Retirement rules belong to roles, not to catalogue numbers. Hot-zone entry gloves are typically single-mission or fixed-entry items with mandatory post-mission inspection and no return to stock without a recorded test. Warm-zone and decontamination-line gloves can run on cumulative hours and cycle counts with periodic leak testing. Support and training gloves should have a formal downgrade route, so stock retired from live-agent work stays useful.
A workable structure applies four tiers in order:
- Gate: packaging date or service date exceeded - withdrawn, no discretion.
- Budget: cumulative hours or decontamination cycles used up - withdrawn.
- Inspection: cut, pin-hole, stiffening, delamination, separated cuff seam or failed inflate test - withdrawn.
- Event: known agent contact, unknown liquid, or contaminated storage - withdrawn regardless of appearance.
Disposition is part of the framework, not an afterthought: return to service, downgrade, quarantine pending a technical decision, or destroy. Each route needs a signature and a date, because that record is what an auditor will ask to see.
What buyers should require in writing
Ask suppliers for the service life they will defend and the conditions that void it; permeation data with test standard, thickness and named chemicals; the decontamination agents the glove tolerates; batch marking that survives repeated washing; a cuff range wide enough to rotate stock without mixing roles; and a retirement record format they are prepared to support. A supplier who cannot say when a glove stops being protective has, in effect, sold an open-ended claim.