Firefighters response to the Harry S Truman Apartments in East Cambridge the morning of April 24. (Photo: Cambridge Fire Department via Twitter)

Tenants were sleeping when a fire broke out in one apartment of a public housing development for elderly and disabled people on April 24. The blaze left all 59 units damaged from water but caused no injuries, officials said. Cambridge Housing Authority workers were already on the scene and evacuating some tenants when the fire department arrived to answer the 2:22 a.m. alarm, which went off automatically, acting fire chief Thomas Cahill Jr. said.

Firefighters “quickly extinguished” the fire at Truman Apartments on Eighth Street in East Cambridge and cleared the scene by 5:30 a.m., but some firefighters remained to help manually operate the elevator, which had been damaged, Cahill said. Meanwhile, the housing authority first made sure residents were safe and then brought in as many as 200 pieces of equipment to deal with the damage, Cambridge Housing Authority executive director Michael Johnston said.

Sprinklers going off throughout the building soaked all 59 apartments and left standing water on the eighth floor. “The big thing right now is mold,” Johnston told the authority’s commissioners at a regular meeting two days after the fire. At that point, three residents were in hotels and one was staying with family members. Giant fans operating to dry out the walls brought complaints about noise, he said.

Johnston said Tuesday that the authority had restored a “healthy and safe environment” in the building and the elevator had been repaired.

Fire chief Cahill said the fire was caused by “careless disposal of smoking materials.” That reason “is unfortunately a very common cause of fires, particularly with the elderly who many times live alone and have oxygen-based systems that tend to fuel fires in certain conditions,” Cahill said.

A pack of cigarettes was found on the couch of the apartment where the fire started, with “an oxygen machine off to the side,” Johnston said at the board meeting April 26.

The authority prohibits smoking inside apartments and anywhere on CHA property except in designated smoking areas outdoors at some developments. The policy was adopted in September 2013 despite strong protests from some tenants; others supported it. It went into effect the next August.

Asked whether the tenant of the apartment where the fire started had returned, Johnston said he could not discuss individual residents without their consent “but we can confirm that with any serious issue, CHA uses all resources necessary to enforce the lease through the Housing Court process.” He also said the authority hadn’t been notified of the fire department finding.

The smoking ban calls for residents to get a verbal warning for a first violation, then a written warning, then a request for a conference with management. CHA “may” initiate eviction proceedings with a fourth violation. The policy requires the authority to offer smoking cessation tools to tenants at each step of the process.

Johnston could not immediately say how many actions the authority has taken to enforce the ban.