Warehouse and plant storage looks like a dry environment in the brochure and often is not in practice: wash-down bays, cold stores, coastal facilities and chemical storage all expose drawer hardware to moisture and corrosives. Choosing the right coating at specification time prevents a whole rack of seized drawers later.
Know your environment first
The coating decision should start with the room, not the catalogue. Indoor dry storage: zinc plating is fine. Humid or wash-down areas: black zinc or powder coat. Coastal, chemical or refrigerated environments: 304 stainless. If in doubt, ask for a salt spray comparison on your actual environment conditions — it is cheaper than a recall.
Comparing the finishes
Zinc electroplating (blue or clear) is the baseline — 24–48 hours neutral salt spray. Black zinc adds a dye topcoat that passes 48–72 hours and suits darker cabinet interiors. Powder coating builds a thicker barrier and survives scratching better, at a higher cost per part. Stainless removes the coating question entirely for the worst environments.
Salt spray hours: the number to quote
Neutral salt spray (NSS, ASTM B117) is the standard yardstick. When you request a quotation, state the hours you need — for example “48 h NSS minimum” — and the supplier will quote the finish that meets it. Salt spray testing and material certificates are run on demand, and the report ships with your order.
Where stainless pays for itself
In coastal warehouses or wash-down plants, a stainless slide outlasts several re-plating cycles of zinc hardware — the premium pays back in avoided labor and downtime. Our stainless line uses 304 for rails, balls and rivets so the whole assembly corrodes uniformly.
Coating selection is an environment question, not a price question: measure the humidity and wash-down exposure first, then pick zinc, black zinc, powder coat or stainless. Salt spray hours are the honest comparison metric, so write the required hours into the RFQ and let suppliers quote to it. Coastal and wash-down plants usually find stainless pays back in avoided downtime within the first service interval.
