Five people were killed on Wednesday after the fire burned down the tent-like isolation unit outside the main building of the private facility in Gulshan.
There were no firefighters, fire drill or a fire team to deal with the disaster, a member of the panel said, adding only three of the 11 fire extinguishers at the wing had not expired.
Three units of the Fire Service and Civil Defence tamed the flames within half an hour, but not before the four-room structure was completely burned down. The dead included four men and a woman.
They were identified as Md Mahbub, 50, Md Monir Hossain, 75, Vernon Anthony Paul, 74, Khodaja Begum, 70, and Riaz Ul Alam, 45.
The authorities could not immediately ascertain the cause of the fire, but after speaking to relatives of the patients, they suspect that it may have been caused by a spark in an air conditioner, added Sudip.
Debashish Vardhan, deputy director of the Fire Service and Civil Defence, is heading the four-member panel investigating the incident.,
DNCC Mayor Atiqul Islam also criticised the hospital's lack of fire safety protocol after visiting the scene on Thursday.
"People come to the hospital seeking recovery from their sickness but here they died in a fire," said the mayor.
“This is really unfortunate. I would request the authorities of all hospitals to attach the necessary important to fire safety.”