Mosque authorities sensed leak over a month ago
The explosion at the Baitus Salat Jame Mosque in Narayanganj was completely avoidable as the mosque’s managing committee suspected the leak on August 2, according to an independent probe body.
The gas continued to accumulate in the mosque through the floor tiles for over a month before finally igniting and exploding on September 4. At least 31 people lost their lives in the blast near Narayanganj’s Fatullah area during Isha prayers.
If the leak had been fixed before then, the disaster would never have taken place.
The mosque authorities said they had turned to a temporary solution for the gas leak, involving a tarpaulin floor and plaster, since Titas Gas officials had rejected their request for repairs without a bribe.
The probe body formed by the Electric Safety Security Association of Bangladesh (ESSAB) found that the mosque was filled with gas because of the leaks in the gas line. The gas ignited when the muazzin of the mosque tried to operate a manual changeover/ electric switch.
The gas was mostly natural gas (94% methane) with hydrocarbons accounting for the remainder, said the probe report.
“The leak occurred at a low-point drainage pipe on the recirculation line with hydrogen-rich gas in the reactor part of the plant, on the line into furnace H-1202,” said the investigation report prepared based on interviews, site inspections, document reviews and investigation, by the external fire safety officer of BFSCD.
The investigation team also found four nonconformities: the mosque was not maintained to an acceptable standard, risk assessment was inadequate, information was not provided about the risks associated with the work, and personnel control was inadequate during the evacuation.
There was no ventilation in the air conditioned room of the mosque. The pipe had been stripped of insulation and was ready for inspection on the Titas end on the day of the explosion, said the probe body.
Just after 1pm on September 4, the mosque committee called the Titas authorities seeking clarification on the gas leak.
“The pipe appeared to be standing a little open, out through mud and water, and creating bubbles. It was thought the air-conditioned prayer room area could be leaking. The acting assistant operations supervisor (herein muazzin) for the praying area was working on a new electric line. He noticed power was off and he went to the manual changeover area to switch to alternative power. When he switched the power, there was rumbling, a flash, and an explosion,” the report said.
ESSAB probe committee head Md Al Imran Hossain told Dhaka tribune the number of leaks does not matter, as one leak is enough to fill up the mosque if not repaired in a timely manner.
“It was surprising to us that gas had entered the mosque through the floor tiles, as there should have been concrete beneath. Such a situation can only happen if the floor was not constructed properly,” he said.
ESSAB submitted the report to Bangladesh Fire Service & Civil Defence on Sunday.
The probe by Fire Service & Civil Defence
Meanwhile, a materials technology investigation by Bangladesh Fire Service & Civil Defence in Dhaka concluded that the leak and fracture were caused by corrosion under insulation (CUI).
“The pipe had suffered substantial external corrosion, reducing its wall thickness to zero in parts of the circumference. Internal corrosion was insignificant,” the Fire Service investigation report said.
The probe body said the mosque had not been maintained to an adequate standard. Inadequate maintenance meant corrosion under insulation on process piping was not discovered and repaired, which led in turn to a gas leak and electric ignition.
The prayer area lacked automatic ventilation or opportunities for remote operation of this. Parts of the mosque do not have natural gas detectors or fire detection systems.
The report identifies poor control of potential ignition sources (manual changeover) and inadequacies in documentation at the facility.
The report is not finalized yet.
Lt Col Zillur Rahman, head of the Fire Service committee and director (operations and maintenance), told Dhaka Tribune that they would submit their report on Thursday.