There are wakes scheduled Thursday for both Lieutenant Steven Velasquez and firefighter Michel Baik, who died while battling a house fire last Saturday.
The Waterbury, New York and Boston fire departments will help Bridgeport at both funeral services.
The state medical examiner's office says Baik died of smoke inhalation, while further study is needed Velasquezr.
Velasquez and Baik were searching for people in need of rescue and ventilating the house when they sent out mayday calls, officials said. They were found unconscious.
The fire department has not had problems with its breathing equipment, which is checked daily when firefighters come on duty, Capt. Edward McCann said.
The air tanks give a warning of about five minutes when they are getting low, he said, but firefighters can become disoriented or have their exit blocked by fire, smoke or falling debris.