As thousands of health care workers watched raptly, a federal government doctor clad in a green impermeable gown, bootees and a face shield that looked like a welder’s mask demonstrated the latest protocols for fighting Ebola at a huge training session in New York on Tuesday.

It was the highlight of a conference at the Javits Convention Center in Manhattan that brought together janitors, security guards, doctors, nurses and other workers from hospitals across the city who have been anticipating the possible arrival of the virus in New York and wondering whether they are sufficiently trained and equipped to deal with it.

The session, more than three hours, turned out to be part pep rally and part training conference, as Gov. Andrew M. Cuomo and Mayor Bill de Blasio kicked off events with speeches that took pains to pay tribute to 1199 S.E.I.U., the powerful health care workers union that was one of the organizers.