The men had been inspecting a temporary repair patch on one of the pipelines inside the platform's utility leg when they were engulfed in a gas escape inside.
A report in the national Scottish newspaper, The Scotsman, revealed earlier this month that Brent Bravo had been shut down only three weeks before the two men died, for work on the 27-year-old platform's summer maintenance program. Yet the men were sent down into the utility leg to check on the pipe repair while the platform was back in full production, importing gas, oil and condensate under high pressure.
A spokesman for the HSE told The Scotsman: "The cause of death of the two men was suffocation. Initial lines of inquiry include examination of pipework, temporary repairs to pipework, control valves and their operation, and aspects of the permit-to-work system.