What’s wrong with “letting go” during dives?

This article, Why do we pee in our wetsuits?, shared by a fellow diver on her Facebook really caught my attention. Well, I have to first admit I am very guilty of it but more that I have never seen it as an issue or problem before!

I distinctively remember one Dive Master suggesting this very method to keep warm during a pre-dive briefing for a dive site known for its cold water temperature. As someone who is very susceptible to feeling cold and really disliking it, this is such welcoming news! I mean I can’t possibly bring heat packs from Daiso with me into the deep blue?!

Thus I read the article with great interest. Unfortunately, just into the third paragraph, alarm bells rang off in this Physics teacher’s head as it began with “water is an excellent conductor of heat..” This doctor/blogger/author has got her Physics concepts so wrong. Divers feel cold underwater purely because the water temperature can get as low as 15 degrees Celsius and thermal energy is transferred in liquids mainly by convection and not conduction. I guess to be fair, it was difficult for me to grasp the various Biology-based concepts she listed in the article as well.

But as any good science communicator would proceed, I decided to look for more related articles to verify this article’s argument. According to dive physiology, immersion diuresis is a natural phenomenon whereby a human body reacts to a cold environment by shifting blood away from the extremities and towards the core and vital organs to minimise heat loss. This in turn triggers the kidneys to increase the urine production which results in the diver feeling a need to pee.

So, since there is a scientific reason behind this inevitable need and almost all articles giving the approval to do so, I conclude that there is nothing wrong with letting go during dives. Moreover, I learnt that urine is very sterile when one is properly hydrated and free from infection thus is not as if I am adding to water pollution. I am certainly going to continue with this method of keeping warm, even if it is only a short-lived relief from the frigid cold as it will actually lower one’s body temperature. But that will be another article for another time.




2 thoughts on “What’s wrong with “letting go” during dives?

  1. zhihan says:

    “Water is an excellent conductor of heat..” is probably stated in relative terms. Thermal conductivity water is definitely much higher than air, which is probably the case of comparison here..
    This reminded of my sec school teacher telling us that poor Leonardo died of hypothermia after Titanic sank because of the high specific heat capacity of water. (This is not entirely true as the relation between heat capacity and thermal conductivity is not as simplistic..)
    I learn here the physiology of the urge to pee in the deep blue=) But i can’t figure out why peeing will help to warm you up!


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