Ensure to check your Depth
Wreck Diving does get deep
Safety Stops are a must
If you’re planning a deep dive, plan for all reasonable contingencies. Use redundant equipment for vital things like your depth gauge (probably the most important redundancy). Carry at least one dive light, but a secondary is never a bad plan. Talk to local divers and find out the conditions that you might be facing when you get to the bottom. If it’s a wall dive, watch your depth gauge(s) like a hawk! Some computers can be set for deep stops, so this is a good option as well. Situational awareness is a trait that good divers seek to develop as much as possible over their diving careers. In a deep dive, it’s as important as it would be on a night or wreck dive. Paying attention to your depth, watching your dive buddy and yourself for narcosis and keeping track of your air are the most key things to watch. And finally, brush up on your certifying agencies emergency decompression stop rules and write them on your slate so you don’t forget. You’re already increasing your risk of DCI, so there’s no sense increasing it further by blowing your tables and not taking the needed stop. Safety stops aren’t optional with deep dives!
Planning and conducting deep dives is a big part of diving for me and many other people, particularly the Tec set. While you are able to go to whatever depth you want, it’s good to get the extra training (and master Dalton’s Law) before you just plunge in. 40m is a long way from the surface and a safe dive is a good dive!