Rick wrote:

"Michael Daly" wrote in message
ble.rogers.com...

On 1-Feb-2004, "Robert11" wrote:


I'm confused on this point, as I guess I keep getting back to a skin

divers

neoprene, which is of course totally porous, and relies on body heat to

warm

the thin water layer that ends up
next to the skin.

Neoprene is not porous. It is a closed cell foam and is waterproof. If

you

want it to be porous, you poke holes in it. I've seen neoprene socks like
that _once_.



I guess that my wetsuit is a drysuit, then. Strange how that cold water that
comes through the suit somehow.

Neoprene is porous, but it does not allow the water trapped in the material
to circulate. The air trapped in the foam and is warmed by the body, which
provides insulation. It also stops water from circulating around the body,
keeping fresh cold water from the body.

From the following website:

http://216.239.53.104/search?q=cache:Yk3bpqVxWZwJ:www.tdc-dive.co.uk/Factsheets/TDC%2520Tip%25205%2520(Dry%2520Suits%2520-%2520Using%2520and%2520Choosing).pdf+%2Bneoprene+% 2B%22wet+suit%22+%2B%22thermal+properties%22&hl=en &ie=UTF-8

"Wet suits let water into the suit which forms a layer in between the suit
and the skin.
1. the neoprene that the suit is made of contains small bubbles of air which
trap
warmth in the suit. This can be affected by depth, as the suit compresses
with increasing depth and the thermal protection the suit offers can be
reduced
2. the water the suit lets in is trapped in the suit and the body warms the
water
up. It is important to get a well fitting wet suit to prevent the water
from
"flushing" in and out which then necessitates the body warming the water
over and over again, and during which time the diver gets cold."

Sounds porous to me. From personal experience, it feels it, too.

None of that says the neoprene material is porous - it just says that a
wetsuit isn't waterproof and given the lack of seals and a normal type of
zipper that's not at all surprising. I have both a neoprene wetsuit and a
pair of neoprene socks. Neither lets water through the material itself,
but both have some leakage at seams and the wetsuit leaks at the zipper.
Since they both lack seals they also let in water around my ankles (and
arms/neck for the farmer john).

The description above mentions air bubbles trapped in the material which
would be a characteristic of closed-cell, non-porous material.