In New York City, where a vaccine mandate for municipal workers is now in effect, New York City Fire Department union officials are expecting dozens of fire companies to be closed Monday, but the department said no firehouses have closed and no response times have been affected as a result of the union’s limited job action.

       More than 12 fire companies have been closed daily since Friday due to a large number of firefighters calling out sick.

       MORE: Where NYC stands in COVID-19 vaccine mandate for city employees

       Firefighters Association President Andrew Ansbro and FDNY-Fire Officers Association President Jim McCarthy said at a Monday news conference that they tried to negotiate for more time for members to be able to file for exemptions, decide on retirement or get the shot.

       Eduardo Munoz/Reuters

       New York City Fire Department (FDNY) Uniformed Firefighters Association (UFA) President Andrew Ansbro and FDNY-Uniformed Fire Officers Association President James McCarthy attend a news conference as the city's COVID-19 vaccine mandate deadline approaches at Ladder Co. 24 in Manhattan borough of New York City, Oct. 29, 2021.

       Nearly all New York City municipal workers, including police officers, firefighters and EMTs, had until 5 p.m. Friday to get at least one shot or be placed on unpaid leave, starting Monday. While the official deadline was Friday, those who got vaccinated over the weekend will not be placed on leave.

       Seth Wenig/AP, FILE

       New York City firefighter emergency medical services personnel are vaccinated against COVID-19 at the FDNY Fire Academy in New York, Dec. 23, 2020.

       Mike Segar/Reuters

       New York City Fire Department union members, municipal workers and others demonstrate during a protest against the city's COVID-19 vaccine mandates in New York City, Oct. 28, 2021.

       About 9,000 municipal workers were on leave without pay Monday, representing about 6% of the total city workforce, said Danielle Filson, the mayor’s press secretary.

       "Mandates work," Filson said. "That number will continue to decrease. The remaining have pending accommodations/exemption requests. They are working and subject to weekly testing."

       MORE: New York City mayor announces COVID-19 vaccine mandate for municipal workers

       Of the municipal departments, the Department of Corrections, which faces a later compliance deadline, currently has the most unvaccinated workers, followed by the FDNY, which has an 80% vaccination rate.

       Supervisors will begin checking firefighters’ vaccination status when the dayside tour starts at 9 a.m. and sending home members who are unvaccinated.

       ABC News' Alexandra Faul contributed to this report.