Ecolab has supplied Oxford's vaccine-makers, supermarkets such as Tesco and England's National Health Service (NHS) with products during the pandemic this year, and supplies three million commercial sites globally.
In the summer, it signed a deal with the NHS to supply 5 million litres of hand sanitiser, which Sam De Boo, Ecolab's President for Western Europe, said was the firm's biggest one-time customer order.
But with two COVID-19 vaccines on course for possible approval in Britain before the end of the year, that demand will be tempered.
"It will of course go down from these current peak levels (but) we do believe it will be higher than 2019," De Boo told Reuters on Thursday.
"For hand hygiene, we think that still the market will be 30% to 50% higher than it used to be. But of course, where we currently see an explosion of ... five to ten times more - that will normalise."
Ecolab said on Thursday that two products - a hand-rub and a surface disinfectant - had been shown to be specifically effective against SARS-CoV-2 following tests in Germany.
The World Health Organization says the coronavirus can be spread via surfaces though the main route is through droplets.
British health minister Matt Hancock has said society should start getting back to normal after Easter, but that increased hand-washing was a "no regrets thing" that would become commonplace.
De Boo said: "In the past, when you did not see, let's say any dirt or any soil, you felt it was clean and it was trusted. People who have ... lived through this pandemic, I think, will have a very different understanding on that going forward.
"I think there is a mindset change."
(Writing by Alistair Smout; editing by Stephen Addison)
By Jason Cairnduff