Record Number: 1298 CIS Descriptors: UNSAFE ACTS IMPLOSION OIL BURNERS FAULTY SUPERVISION INJURIES PRESSURE TESTING BUILDING INDUSTRY FATALITY REPORT REPORT CHARACTERISTICS: DONOR: Office of the Chief Coroner JURISDICTION: Ontario REPORT TITLE: Verdict of Coroner's Jury INDIVIDUAL PRESIDING: Dr. J.F. Leeson, Coroner PLACE OF INQUIRY: Cobourg DATE OF INQUIRY : 1982-12-15 INFORMATION ABOUT DECEASED: NAME: Harold G. Parker OCCUPATION: Mechanic INDUSTRIAL SECTOR: Building industry ACCIDENT INFORMATION: DATE OF ACCIDENT : 1982-09-23 PLACE OF ACCIDENT: 75 White Street, Cobourg BRIEF CAUSE OF DEATH: Multiple injuries. BRIEF MANNER OF DEATH: Boiler truck exploded when the pressure was being tested after a tear had been welded. ACCIDENT DESCRIPTION: It became apparent at the inquest that the three men who made the decision about how the oil heater from the asphalt plant was to be repaired and subsequently tested were operating under a misconception. This misconception was that the oil being heated in the heating unit was pressurized at 45 pounds. In actual fact, it was in direct communication with a tank above it which, in turn, was vented to the air, so that the actual pressure in the system there was probably two or three pounds. Exiting from the heating unit, the pipe went through a pump which raised the pressure to 45 pounds in order to carry it through the external piping that went into the asphalt heater and returned the somewhat cooled oil to be reheated and recycled. The repair and previous repairs which had been made on the lining of the unit were reasonably satisfactory repairs and had nothing whatsoever to do with the failure of the unit. This failure occurred when they undertook to test it using air. Apparently none of the three men involved realized that the tank being vented to the air automatically meant that the pressure in the oil was almost zero and they decided to air test it at 60 pounds, thinking that to be only 33% over the operating pressure, whereas it was many times the usual operating pressure. The witnesses were of the opinion that if it was to be tested with air, it should be at no more than five or seven pounds pressure and they were also quite emphatic that air or any gas is not a good thing to use in testing any sort of pressure vessel but rather they should be tested with water or oil. A fluid simply spurts or leaks out if the vessel fails, whereas gas will explode. Mr. Parker was an experienced mechanic although not an engineer. He had dealt with this plant for many years and should have known better than to enter the container during air testing. He himself apparently played an active part in the decision-making that led to the accident and was just as much at fault as the other two men in the plan they undertook and was the one solely at fault in entering the vessel while it was pressurized. No one either told him to go into the vessel nor, as far as we know, did anyone tell him not to go into the vessel. The air pressure was in a thin layer around the outside of the heating chamber between the inner and outer liners, and the inner liner came away at the weld, imploding and causing massive bodily injury and undoubtedly immediate death. Had the unit been inspected the day before, it would have done little good unless the inspector had spelled out to them the testing procedure. RECOMMENDATIONS ISSUING FROM INQUIRY: 1. Responsibility for the safety and welfare of all employees and the implementation of approved procedures rests with senior management. All employees have a shared responsibility in setting, following and ensuring all unsafe conditions are reported. The jury recommends that Harnden and King Construction implement and enforce a comprehensive safety program including the following: a) written, qualified and approved procedures b) routine inspection and corrective action c) regular involvement of all employees d) individual training. 2. The foregoing recommendation be supported by the proper government agencies, to include all similar industrial and construction establishments. This would involve regular government inspection to ensure programs and regulations are adhered to. 3. "ALL" similar vessels (0 to 15 psi) be classified complete with identification plates and be included in the Pressure Vessels Act. This would mean for repair and inspection purposes, the government agency would be notified prior to any work commencing. 4. Immediate notification be issued to all users of similar units warning of potential hazards. COMMENTS ON RECOMMENDATIONS BY CORONER: None of the Ministries involved seemed to acknowledge that they were responsible for supervision or inspection of safety of this particular type of apparatus, inasmuch as it was not a boiler, even though it operated at temperatures up to 300 deg.F, and it was not a pressure vessel because it was vented to the air (except during the fatal testing). Mr. Murdoch from the Ministry of Consumer and Commercial Affairs stated that had it been classified as a pressure vessel, it would have been listed with the Department and it would have had to be reported to them prior to the repairs being done and an inspector would have been there in all probability for the actual testing. Moreover, the inspector would not likely have acquiesced allowing air testing and, had he allowed air testing, would have insisted on lower pressures and cleared the area in case of explosion. It would therefore appear desirable to try and organize some sort of system that would place these apparatuses under some type of supervision by knowledgeable people to try and prevent a future similar accident. At the very least, these units should be clearly marked with a plate stating that they must not be pressurized. The Ministry of Labour, who through their Mining Branch, are looking after asphalt plants in general, are apparently trying to notify owners of such plants of this hazard, according to Mr. Mitchell, who was the representative called as a witness. This was a good jury and I believe they arrived at a good verdict. Their recommendations are appropriate. I would add to their recommendations that a strong letter be written to the manufacturer of this unit in the United States to make him aware of this accident, with a very strong suggestion that he track down their units and label them in such a way that no one is apt to pressurize one of them in the future.