Dyfed-Powys Police/Angle Lifeboat/HM Coastguard A large emergency services presence was seen in Milford Haven, as police, RNLI and HM Coastguard arrived to assist in the saving of a diver. All services were present on Sunday, July 11 on a wet and windy waterfront as a diver in the Haven waterway was suffering from decompression sickness, commonly referred to as 'the bends.' Decompression sickness occurs when there is a rapid decrease in pressure, usually caused by divers ascending to the surface too quickly. This causes nitrogen bubbles to expand in the bloodstream, which can be fatal in extreme cases, such as if the bubbles expand within the brain.