The US Bureau of Safety and Environmental Enforcement has worked with GE to notify operators of the issue, which first after the bolts on an H4 Connector fractured and caused a leak of synthetic base mud.

Bolt failures were also reported in two other H4 connectors, BSEE said in a 29 January safety alert.

“Notified companies are being directed to inspect their BOPs to ensure that they are safe to operate,” bureau spokesman Nicholas Pardi told Upstream, adding that “less than a third” of rigs were affected.

“The