Ask Joe & Larry

How thick of a suit do I need for diving in different water temperatures?

It's kinda' hard to give an exacting answer to this question since different individuals have different tolerances to temperature. I've been diving in a full 3mil suit next to someone who wore just a bathing suit, and we both were comfortable. I'll answer this question based on my preferences - which seem to be pretty close to the average I've seen in other divers.

It's important to note that water removes heat from your body 25 times faster than air does - so temperature that is comfortable in air can cause hypothermia. Our body temperature is 98.6, and dropping below that can cause shivering, or worse... Even in 80 degree water - if you are submerged long enough, you could suffer from hypothermia.

When looking at suits - there are two variables to consider. How much coverage the suit affords, and how thick the material is. The material thickness is normally given in millimeters (mm). For example a 2.5mm suit is 2 and one half millimeters thick, (a little less than the thickness of a couple of dimes stacked up) or a 6.5mm suit is 6 and one half millimeters thick which equates to approx a 1/4 inch.

Some suits will have two numbers such as 3/2. This means the majority of the suit is 3mm, but they drop to 2mm thickness for the sleeves and legs to give more flexibility. To get the same warmth with thinner neoprene throughout, you can choose a titanium lined suit. This type of suit uses a mico thin layer of titanium in the laminate that helps reflect body warmth back to you and makes a thinner suit warmer without the added bulk.

I find that even in warm water (82 degrees +) I still am more comfortable in at least a shorty. Besides the thermal protection, it gives me some abrasion protection from the straps of the BCD. (Not to mention you look cooler if you're wearing a suit.)

If the temp drops below 80, or if you are diving where you might be surrounded by jelly fish, you will probably want to be in a Full 2.5mm Suit. A full 2.5 suit is probably good to the high 70's.

If we dip into the mid 70's, you'd want to get into a 5/3 suit. As you can see... Already we have to own quite a few suits for our changing temperatures. To be more versatile, you can get a Shorty Vest and a Full Suit. Then when the temp is mid 80s, wear the shorty vest. If it gets colder, wear the full, if colder still pull the vest over the shorty which will give you the equivalent of a 5/3 titanium lined suit.

If the temp drops into the low 70's, or below - it's normally time to start looking at a 6.5mm Farmer John and Jacket suit. Add a hood and some gloves, and I stayed warm for a 4 hour Walker Texas Ranger shoot in 42 degree water.



Stay Warm!

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