SAINT JOHN, New Brunswick–At least four separate investigations were under way Wednesday into Tuesday’s explosion and fire at the Irving Oil refinery that left a man dead and alarmed many Saint John residents.

In a press conference Wednesday afternoon, refinery manager Bob Chalmers said Irving Oil had hired consultants to investigate the accident.

“We want to understand exactly what went wrong and what safeguards are needed to ensure it never happens again,” said Chalmers, who estimated the study should be complete in a few weeks.

The Saint John Fire Department has assigned its top investigator to determine the cause and the origin of the blaze that killed 45-year-old Bill Hackett, a facilities technician who worked at the site for 23 years.

Officials from the Workers Health and Safety Compensation Committee will spend four or five days on the site. Investigators will be trying to find out if the accident could have been prevented and if the company had violated any regulations.

The environment department is also involved. Staff took samples from land and air and water in the area. The company, working with environment officials, has been performing its own air quality tests.