Bulk soap seems like a good idea — buying more product reduces overall costs, including shipping. While it seems almost counter-intuitive, bulk containers of soap are likely to become contaminated with bacteria because they are not sealed. Being re-opened again and again to fill or top off dispensers serves as an invite for bacteria. That bacteria is not killed while in contact with the soap, and can contribute to the spread of illness for users, which is especially dangerous in public facilities and institutions.
Sealed bags or cartidges of soap, that simply fit into dispensers, are the best way to avoid contamination. It is also important to make sure dispensing nozzles are cleaned and disinfected regularly, as they are a source of product build-up and can come into contact with hands.
Cleaning: Soap & Dispensers

Avoiding Soap Dispenser Contamination
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