The heat is long as you’ve turned it on.

  Thermalution Vest When I learnt to scuba dive during the middle of winter last year, everyone thought I was crazy. Considering I won’t go in a swimming pool unless it’s over 28 degrees Celsius, it’s understandable why they didn’t understand my desire to spend copious amounts of time under the practically-arctic Sydney sea. But learning during winter meant that I saved a couple of hundred dollars, while becoming well-versed in the universal scuba signal for “I am cold”.

Had the Thermalution heated vest been available to hire during my course back then, Mick Fanning couldn’t have stopped me from wearing one. But while this time last year my chattering teeth sounded like a tap dancing troupe, just last weekend I was lucky enough to go diving with said Thermalution vest.

The best part is, I can give you a really good comparison between diving without it and diving with it… because I forgot to turn it on for the first dive. Yup. I’m not sure what’s more embarrassing – the fact that in my excitement to be toasty I didn’t hold down the little “on” button, or the fact that I raved about the vest’s amazing heating powers BEFORE I realised that it hadn’t actually been activated. I guess that’s testament to the quality of the discounted Pinnacle Cruiser 7mm wetsuit!

When I actually switched the vest on while I was standing on the shoreline, it made an almost instant difference! Within just a few seconds I could feel my back warming up and actually had to turn it off again because I was too hot. Luckily this time I remembered to switch it back on when I entered the water! Usually on a second dive – especially in the middle of July – I’m shivering after a couple of minutes and have to think warm thoughts for the rest of the dive. This time, with the vest switched ON, I was comfortable for the duration of the dive. It wasn’t like having an electric blanket wrapped around me, but it definitely helped to keep my core warm and made the dive so much more pleasant. Just before it was time to surface I could feel my gloved fingers start to chill, so I hugged my chest and could feel the warmth come through.

There are three heat settings on the vest – low, medium and high. Holding the switch for two seconds turns it on (a critical aspect of using the device apparently!), and just flicking the switch changes the setting. Because the battery was still fully charged on my second dive, I spent the whole time with it set on high. If you’re only doing the one dive that would be fine, but usually you would want to start off with it on low for the first dive before turning it up for the second. This saves battery power (you don’t want it running out before you’ve finished or you’ll be in for a rude shock) and also accounts for the heat you lose during the first dive – you’ll require more “oomph” from the vest during the second dive. Depending on the heat settings, you can expect the pair of batteries to last approximately two hours – or longer if you don’t have it switched on…