Assertion: diver's system | /r/ObjectUse | used in the north sea oilfields
Facets:
value: between early 1986
type: TEMPORAL
value: between the early 90s
type: TEMPORAL
Source sentences:
text: A variant of this system used in the North Sea oilfields between early 1986 and the early 90s was the Oceantech Minibell system, which was used for bell-bounce dives, and was operated as an open bell for the descent, and as a closed bell for the ascent.