Primary Light for Cavern Diving

[js1221]

Do the requirements for a primary light for cavern diving differ from those of a primary light for cave diving?

I'm interested in getting my Cavern Diver certification and in the gear required it calls for a primary light and a backup. I understand that cave diving has specific requirements for primary lights but does that apply to cavern as well? Can I use my recreational dive lights for cavern? If so, is the a minimum lumen recommended or beam angle? What about the backup, should it be the same as the primary?

 

[rx7diver]

Do the requirements for a primary light for cavern diving differ from those of a primary light for cave diving?

I'm interested in getting my Cavern Diver certification and in the gear required it calls for a primary light and a backup. I understand that cave diving has specific requirements for primary lights but does that apply to cavern as well? Can I use my recreational dive lights for cavern? If so, is the a minimum lumen recommended or beam angle? What about the backup, should it be the same as the primary?

When cavern diving, one never leaves the daylight zone, correct?

rx7diver

 

[js1221]

When cavern diving, one never leaves the daylight zone, correct?

rx7diver

That is my understanding, you will always be able to see daylight.

 

[boulderjohn]

I have seen different people interpret the rules differently, meaning there are some conflicting rules. Some say your primary light in a cavern is natural light. Others say you only need to be able to see natural light from the entrance. Either way, you will not need the kind of primary light you would need in a cave.

That paragraph was all about the light you need. This is about the light you want. Depending upon the size of the cavern and the kinds of formations present, your experience can be greatly enhanced with a powerful beam that reveals things you would otherwise not see.

 

[Wibble]

Primary needs some form of handle, can be a glove or Goodman, either umbilical or stand-alone. These days stand-alone primaries are much better priced. Umbilical torches can be very expensive as they have long burn times and very bright, often too bright.

Backup needs to work. Non rechargeable batteries with a screw head, e.g. twist to turn on, is probably the most reliable. If it’s moderately sized it can be stored in a pocket or bungeed to your harness.

 

[rx7diver]

That is my understanding, you will always be able to see daylight.

Yes, *direct* sunlight (rather than reflected sunlight, or refracted sunlight, or ambient light). So, your handheld dive light is primarily for looking at cave details.

ETA: My Cavern training (NACD/NSS-CDS) was in 1988. We used the "NSS Cavern Diving Manual" for our text. IIRC, the only "requirements" had to do with having a long enough burn time and a way of securing the light(s) so that they won't become an entanglement hazard.

rx7diver

 

[Rilelen]

Depends on the agency; really you should ask your instructor! Is it a standalone/recreational cavern course, or are you planning to move into cave? You want a tighter beam, probably aim for at least 1000 lumen, with a boltsnap to secure when not in use. I used a DGX600 when I did cavern; I now use it as a backup.

Whatever light you go with, it's helpful (at least I found) to have a soft or hard Goodman handle, so that you're not trying to both hold onto a light and manage the reel at the same time.

 

[tursiops]

Agencies and instructors differ. PADI and TDI simply require two battery-powered lights, no other specs. Since signaling with the light is a requirement, a narrow beam helps. Some say to use a broad beam for the primary so it is easier to look around (which is the point, after all), but it does make signally difficult.

 

[Norwegian Cave Diver]

You may want to consider purchasing the light you would want for cave before taking the Cavern course. Some of the cavern training will include zero vis drills and that will require your light or your light head to be stored on your left chest D ring. The slight advantage would be learning with the light you will use for cave vs a different light. I dive a Light Monkey 32 watt Variable power output and variable focus. It has a battery canister that fits horizontal (sidemount configuration) under my wing at butt level. You will need either a helmet to store your light on (may not allow a helmet in the cavern course) or a goodman handle so you can run a reel/spool and have a light. Enjoy the course.

 

[kensuf]

2 lights for Cavern, a "primary" and a backup. I think the Dive Rite CX1 makes a decent primary for cavern diving (where you still have the sun) and a nice backup for cave diving (which requires 2 backups and a good primary).