Casing (13 3/8″) had been run in the hole and cemented in place. The cement had been displaced using oilbased mud. The welder was instructed to cut off the casing. A hot work permit was developed with the assistance of the operator’s safety rep and contractor supervisor and the hot work permit was issued for this job. To start the job, a torch was used to cut a hole in the casing to allow the fluid above the intended cut in the casing to drain. When the hole was cut the torch ignited the oil-based mud as it sprayed out of the hole in the casing. There was a fire watch standing by who immediately extinguished by the fire and the job was suspended.