Regulator Explosively Failed Under Pressure

An explosive regulator failure sent a hose flailing about wildly

Reported Story

A group of students and I decided to plan a dive trip to a local inland dive site. As soon as I entered the water, my octopus hose started flying around, slapping the water and was making a loud free flow air sound. I didn’t really know what was going on and I was trying to grab my hose, but I couldn’t see what was going on and was unable to grab it initially. My dive buddy, Matt, finally came to my rescue and turned off my air. This all happened on the surface. We found out that the plastic octopus regulator completely broke off from the hose. The regulator second stage fell to the bottom and the hose was left in a free-flowing state. Thankfully, no one was hurt, but it was a little scary because obviously I was not expecting that to happen. Luckily, it was all caught on camera so that we could all relive the moment.


All divers involved in this incident have given permission for the clip to be shown and this incident report published. In case it is not clear, the cause of this incident was a plastic second-stage octopus regulator breaking under pressure. In most regulators the metal fitting at the end of the hose is attached to a metal part of the second-stage which contains the valve that opens when the diver inhales, to give the diver air. In this case the attachment point was also plastic which gave way under the pressure in the hose.

This diver and her buddy are very lucky no-one lost an eye and we are grateful they are sharing this incident to warn other divers. It was also fortunate the regulator did not detach itself underwater while the diver was at depth. Experiments have shown that a tank will empty far quicker if the low pressure hose (for a regulator) bursts, rather than a high pressure hose (to the pressure gauge). This is because the low pressure hose has a larger hole for the air to pass through, where it screws into the 1st stage regulator. All divers should regularly inspect their hoses for wear-and-tear, including every time regulators are rented or borrowed.

This vivid and alarming incident serves as a reminder that in diving, as in life in general, you frequently get what you pay for and diving equipment is certainly worth investing in. After all, it is what keeps us alive underwater.

Peter Buzzacott, MPH, Ph.D.