Solutions Guide
Benzalkonium Chloride 50% — Dosage & Dilution Guide by Application
Benzalkonium Chloride 50% (BKC 50%) is used at different in-use concentrations depending on the application. This guide gives typical active-quat dosages for the main uses; always validate efficacy in your own system and comply with the relevant regulatory limits.
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Typical in-use concentrations
- Hospital hard-surface disinfection: 0.1%–0.4% active quat (1,000–4,000 ppm)
- Food-contact no-rinse sanitiser: ≤ 200 ppm active quat (FDA 21 CFR 178.1010)
- Non-food-contact zones (drains, walls): 1,000–2,000 ppm
- Pool/spa algicide: 5–15 ppm active quat (preventive, weekly)
- Cooling-tower slug dose: 50–100 ppm; shock 100–200 ppm for biofilm/Legionella
Working from the 50% liquid
Because BKC 50% is 50% active, 2 g of product delivers 1 g of active quat. For a 0.2% active (2,000 ppm) cleaning sanitiser, add ~4 g BKC 50% per litre of water. For a 200 ppm food-contact rinse, add ~0.4 g per litre. Prepare fresh working solutions, use potable water, and check compatibility with any co-formulated nonionic/amphoteric surfactants.
Frequently asked questions
How much BKC 50% makes a 2,000 ppm disinfectant?+
About 4 g of BKC 50% per litre of water delivers ~0.2% (2,000 ppm) active quat, since the product is 50% active.
What is the maximum BKC concentration for no-rinse food contact?+
200 ppm active quat, per FDA 21 CFR 178.1010. Do not exceed this for no-rinse food-contact surfaces.
Should working solutions be made fresh?+
Yes. Prepare working dilutions fresh in potable water and verify efficacy; avoid mixing with anionic surfactants, which deactivate cationic quats.