Turning lights on and off under water

[dpspaceman]

Just did our AOW and they say not to turn lights on or off under water due to them getting flooded.

I just received my two Archon dive torches that I wanted to take on some wreck dives... I won't be needing the lights on at all times but only during some swim throughs? Is it true that they will flood if I turn them on and off? THey are twist style.

 

[lemke]

Who is "they"? The comment sounds a little ridiculous.

 

[Jack Hammer]

Not relevant with modern lights. Lights are more reliable these days.

Sent via

 

[Scuba-dan]

Well if that is true then my lights should of been flooded a long time ago. I keep turning them on/off all time.

 

[Nemrod]

When diving in hard overhead where your life may depend upon the light it may not be wise to turn it on and off. N

 

[diver 85]

Hard to change out batteries @ 100 feet--I'd turn em on & off.......

 

[Craig66]

Just did our AOW and they say not to turn lights on or off under water due to them getting flooded.

I just received my two Archon dive torches that I wanted to take on some wreck dives... I won't be needing the lights on at all times but only during some swim throughs? Is it true that they will flood if I turn them on and off? THey are twist style.

At 25-49 lifetimes dives I hope you will not be in a wreck environment where you actually need the lights.

Having said that, turning on and off the lights should not be an issue. Just twist enough so that the light goes off. Keep twisting and they will flood.

 

[dpspaceman]

My lights wouldn't be for deep penetration, but many wrecks here have some swimthroughs that are completely open, and lights would make video much better as they are a little shaded


Sent from my iPhone using Tapatalk

---------- Post added April 15th, 2015 at 11:45 AM ----------

It was just what the instructors said prior to our night dive


Sent from my iPhone using Tapatalk

 

[Craig66]

My lights wouldn't be for deep penetration, but many wrecks here have some swimthroughs that are completely open, and lights would make video much better as they are a little shaded


Sent from my iPhone using Tapatalk

---------- Post added April 15th, 2015 at 11:45 AM ----------

It was just what the instructors said prior to our night dive


Sent from my iPhone using Tapatalk

I understand. Didn't realize it was for video.

The other reason not to turn off your lights at night is that if you drop them it will be far easier to find it if there is light beaming off it.

 

[RJP]

Just did our AOW and they say not to turn lights on or off under water due to them getting flooded.

I just received my two Archon dive torches that I wanted to take on some wreck dives... I won't be needing the lights on at all times but only during some swim throughs? Is it true that they will flood if I turn them on and off? THey are twist style.

Because of the way the Archon lights are designed they are at a somewhat higher risk of flooding when turning them on/off underwater. Largely do to potential user error of backing them off too far when turning them off.

This is not an Archon design flaw... any light with a sealing mechanism that is also the on/off switch is subject to this risk.

There are other modern lights (HIDs for instance) that could possibly flood when being turned off underwater. Essentially running the light creates heat. Heat expands the air inside the light, some expanding air escapes (lights are sealed to keep stuff from getting IN, not so much from getting out.) If the light is turned off, the air inside cools and contracts. In doing so, the pressure gradient between the light and the surrounding water is now greater than it would ordinarily be at that depth. If seals aren't perfect, etc this can potentially increase the chance of flooding. This would typically be at significant depth to begin with.

As mentioned above... not a large issue for most divers with most lights in most situations. But a 1,000yds back in a cave or in the lower-engine room of a wreck... keep your lights on the whole time.