This was my second time at the Guz.Tech conference and it was just as thrilling as the first. The upcoming third conference, scheduled for Saturday 29th November, 2025, promises to be even more exciting. Guz.Tech 2023, the first technical diving conference, was a unique blend of captivating presentations, humorous tributes, and insightful perspectives on technical diving. It featured a captivating presentation by Dom Robinson on ‘The Hunt for HMS Jason,’ a humorous tribute by Mike Etheridge to ‘Britain’s Greatest Wreck Diver – Gifford Pound,’ and a unique perspective on technical diving from skipper Ian Taylor in ‘What Time’s Slack? Technical Diving – A Skipper’s Perspective.’
About
Both this and last year, Guz.Tech was held at the Roland Levinsky Building, University of Plymouth Drake Circus Plymouth PL4 8AA, followed by a group curry at the Mombay Brasserie near Lockers Quay.
Guz
From the Guz.Tech website, the word ‘Guz’ is the old Naval term for the Devonport Dockyard in Plymouth. Where the name originated is still in debate, but the most popular notion is that Guz was the Hindi word for the measurement of cloth – the rough equivalent of a yard. In the 19th Century, when sailors from the South West would return from their world voyages, they would refer to Devonport Dockyard as simply “The Yard”, which was then shortened to “Guz”.
Devonport Dockyard
Devonport Dockyard in Plymouth is indeed colloquially known as “Guz” among naval personnel. The origin of this nickname is debated, with several prevailing theories:
- Hindi Measurement Term:
“Guz” (गज) is a term historically used in India as a traditional unit of measurement for cloth. It refers to a length equivalent to one yard (approximately 0.91 meters). The term originates from Persian and was widely used in the Indian subcontinent before the adoption of the metric system. While the metric system has largely replaced traditional measurements in official contexts, “guz” is still occasionally used in informal settings or among older generations, especially in the textile industry.
- Abbreviation of “Guzzle”: Another explanation is that “Guz” is a shortened form of “Guzzle,” referring to the hearty eating and drinking habits of sailors returning to Devonport. This theory is supported by the Royal Naval Museum, which associates the term with Devon cream teas.
- Radio Call Sign: A less substantiated theory proposes that “Guz” originated from a radio call sign used for the area. However, there is limited evidence to support this claim.
While the exact origin remains uncertain, “Guz” has been a longstanding nickname for Devonport Dockyard within naval circles.
Tech
And although the word “Tech” in the name and title may conjure a hard-core technical conference, it could be further from the truth. It’s a light-hearted and informative gathering of like-minded individuals with the same passion for historic shipwreck scuba diving. Presentations are typically of explorations and expeditions about special interest projects and finds. No, you do not have to be a technical nerd, deep air diver or a CCR diver cert to join the fun, and it was Nick Chipchase’s presentation that cements that ideology alongside Mike Etheridge and Ian Taylor last year, all presentations with witty and playful memories of the diving careers and adventures.
Itinerary
Guz.Tech 2024, held on 30th November 2024, at the University of Plymouth, featured a distinguished lineup of speakers who shared insights from recent technical diving expeditions and discoveries:
- Rich Harpin: Led an expedition in the Moray Firth to identify victims of the First World War German raider SMS Meteor. He presented the team’s findings using photos, photogrammetry, and video.
- Mike Paige: Part of the team that discovered the Royal Navy ‘Q’ Ship Lady Olive and German submarine UC18 after a four-year search off the Channel Islands. Their work was featured in a BBC documentary aired in October 2024.
- Steve Mortimer: Discussed the history and discovery of HMS Hawke, located 110 meters deep and 70 miles offshore from Fraserburgh.
- Graeme Bruce: Shared his experience of discovering five uncharted wrecks in a month in Scotland.
- James Hadlow and Chris Lowe: Documented the ongoing search for the US Coast Guard Cutter Tampa, which sank with the highest American naval combat casualty loss in World War I.
- Nick Chipchase: Delivered a presentation titled “Friends Gained and Lost,” reflecting on his experiences in the diving community.
Nick Chipchase Presentation
What Is Heliair?
In mixed gas scuba diving, Heliair is a breathing gas mixture composed of helium and atmospheric air, blending oxygen, nitrogen, and helium. Unlike traditional trimix, which is carefully blended to achieve specific proportions of oxygen, nitrogen, and helium, Heliair is created by adding a predetermined amount of helium to a cylinder and then topping it off with air. This method simplifies the mixing process, as it doesn’t require handling pure oxygen, thereby reducing potential fire hazards.
However, this simplicity comes with trade-offs. Since air has a fixed oxygen-to-nitrogen ratio of approximately 21% oxygen to 79% nitrogen, Heliair mixtures inherently contain these proportions, which may only be optimal for some diving depths. As depth increases, the limitations of this fixed ratio become more apparent, potentially leading to less efficient decompression profiles and increased risk of nitrogen narcosis compared to custom-blended trimix mixtures.
Despite its limitations, Heliair still has a role to play in the diving world. Heliair can be a practical and safe alternative in remote locations where custom trimix blends are not readily available. It offers some benefits of helium-based breathing gases without the complexities of precise gas blending, making it a valuable resource in certain diving situations.
While Heliair provides a more straightforward approach to gas mixing by combining helium with air, its fixed oxygen-to-nitrogen ratio may not be ideal for all diving scenarios, particularly at greater depths. Divers should carefully consider the specific requirements of their dive profiles and the availability of gas blending resources when choosing between Heliair and other mixed gases like trimix.
In closing, Nick referenced Wrecksite.EU again, advocating its use and that he is updating the database with Shipwreck losses of 1897. He said the database is now looking to add crew lists and ancestry and welcomes any information from any diver.
DDRC Raffle
This year’s raffle was again in tribute to the DDRC Healthcare Hyperbaric Chamber, where I am sure I head that somewhere between £2,000 and £2,500 was raised. Supported by various vendors and suppliers, prizes varied from a £1,000 voucher from O’Three and various day charters from Skindeep, Darkstar and Atlantic Diving, to tee shirts and beanie hats.
Nightlife
