* The site at Irving Oil's Saint John refinery in New Brunswick, Canada, where an explosion and fire occurred on Monday, has been isolated and contained, the company said on Tuesday.
* "We have determined that there are no concerns with regards to air quality," Irving Oil said in a statement on its website.
* The incident resulted in the shutdown of the 320,000 barrel-per-day refinery.
(Reporting by Eileen Soreng in Bengaluru Editing by Chizu Nomiyama)
