The Calgary Fire Department was called out to an explosion that blew the lid off of a containment vessel in the yard of a southeast business on Wednesday morning.

Crews were called out to reports of an explosion in the 7300 block of 30 St. S.E. at about 11:30 a.m.

When they arrived, they found parts of the container and debris scattered over a large area.

The tank was filled with a substance called emulsifier and is used for making asphalt.

The flying debris knocked out a nearby power line on Barlow Trail closing the road in both directions while crews cleaned up.

The head of Health and Safety for the McAsphalt Industries Ltd. says they are looking into the incident.

"We're still not sure. One of our tanks had some vapour that blew the top off the tank instead of going lateral," said Joel Gardner of  McAsphalt Industries.

Some businesses nearby had to close after the explosion.

"It was a little bit scary for a lot of our employees today. We were just working away and there was this huge boom and we went to the window and someone said I think something happened across the street," said Liane MacNeil from Dirtt Environmental Solutions. "I think it's amazing that nobody got hurt today."

No one was injured and Occupational Health and Safety is investigating.