In many stations the glove cache is a shelf in a warm room, and its only record of age is a delivery note. A glove that passed every test at the factory can be out of specification before it is worn, and its appearance will not say so. Storage is a control measure, not housekeeping.
The storage envelope: temperature, humidity and light
Ask the manufacturer for storage conditions in writing and post them at the store room door. Roughly 5 to 25 °C, 40 to 70 % relative humidity, in the dark, is common, but the applicable figure belongs in the technical file.
Heat is the main accelerator. As a working rule, every 10 °C above the stated ceiling roughly doubles the rate at which an elastomer loses flexibility, which is why roof spaces, boiler rooms and unshaded containers are poor stores. Humidity above the stated band drives hydrolysis in some coating systems and mould in liners. Sunlight through a skylight, and ozone from electric motors or welding plant, attack the polymer from the surface inward: first a chalky bloom, later cracks that open on flexing. Sub-zero storage is no preservative either: some compounds stiffen and crack at the cuff.
Packaging and sealing practice
The supplier's bag is part of the barrier system, not transport wrapping. Keep pairs sealed until issue, and do not break a case open to count; count from the label.
Where a multi-pair pack is opened, reseal it the same shift, add fresh desiccant, and write the opening date on the bag. Store boxes flat on shelving that supports the full footprint, never compressed under heavier cartons or on a sharp rack edge, and never hang a pair by the cuff. Keep the store free of solvents, fuels and cleaning concentrates: their vapour migrates through polyethylene over months, and a sealed bag is not a vapour barrier on that timescale.
Shelf life is not service life
Two clocks run on every pair. Shelf life runs from manufacture and describes how long the unused glove keeps its certified properties; service life runs from issue and is consumed by wear, decontamination cycles and exposure.
A pair that has sat in its bag for four years does not gain four years of wear because it looks new, and an inspection pass does not extend shelf life. Once the stated shelf life is reached, the pair leaves the response stock even if the bag was never opened. For buyers, remaining shelf life at delivery is a specification item: set a minimum, reject short-dated shipments, and have dates printed on the case, not only the invoice.
Stock rotation and disposal of expired stock
Rotate on expiry, not on receipt. At goods-in, mark every case with manufacture date and expiry and place the oldest at the front. A two-bin arrangement stops new deliveries being poured on top of older stock; check the store monthly against a written sheet.
Expired pairs go to quarantine with a tag and a reason, out of the response cache the same day. Downgrading them to training use is defensible only as a written decision that no barrier claim is being made. Unused expired stock is normally not hazardous waste, but confirm the local rule and keep it separate from gloves that have seen an agent, which follow the contaminated-waste route. Record lot, quantity, date, method and signature per disposal.
The store room is where certification expires quietly. Treat the shelf as part of the PPE system, and the pair reaching the wearer is still the pair that was tested.