Avoid the Chill

Cooler water temperatures don’t have to thwart your weekend dive plans, but some additional precautions to avoid hypothermia might be in order. Hypothermia can affect anyone, so it’s something to be mindful of as you prepare for deeper dives, longer dives, more dives or dives in water colder than you’re used to.

Signs and Symptoms

When diving, you need to know what you’re up against — it’s how you plan effectively. So, what exactly is hypothermia? Hypothermia occurs when the body loses heat faster than it can produce it. Normal body temperature hovers around 98.6 F (37 C), and hypothermia occurs as that temperature dips below 95 F (35 C). As the body gets colder, it becomes harder for organs to function properly. When left untreated, hypothermia can lead to heart and respiratory system failures and even death.

Common symptoms of hypothermia include weakened pulse, confusion, slow breathing, shivering and even loss of consciousness. Cases of hypothermia vary from mild to severe. A mildly hypothermic person may be shivering and conversing lucidly. For these situations, remove wet clothing and replace with dry insulating and windproof outer layers. A severely hypothermic person may be unconscious and have a very low heart rate. Look for signs of life and assess breathing — if you can be certain the person has no pulse and isn’t breathing, perform CPR.

Hypothermia is not limited to colder conditions; it can even occur in tropical waters. If you’re wearing just a swimsuit or dive skin and are in the water for an extended period, your body temperature will begin to drop. Regardless of whether you’re diving in colder temps or tropical climates, the best way to handle hypothermia is to plan for it and prevent it. 


The right gear will certainly help protect against hypothermia. But before you even start making gear considerations — we’ll talk about gear in a bit — it’s important to develop the right plan. Prior to your trip, consider the topside temperature, water temperature, depth and dive duration as well as the possibility of thermoclines. All these factors play into how cold you may become during the dive.

When you get out of the water, have dry clothes and towels at the ready. Warm beverages — avoid alcoholic ones — and snacks will help restore depleted calories. But if someone seems to be suffering from hypothermia, keep an eye on them. A cold person who is in the initial stages of warming up postdive may be subject to afterdrop. Afterdrop is the continued cooling of a person’s core temperature, as the cold blood from the extremities circulates to the core, causing a further drop in body temp.

In addition to having the right equipment and a proper plan, ensure your training and experience are a match for your dive site. 

Gear Considerations

Dives in cooler waters may warrant some different gear. Assess your current gear and consider your future dive site: Will what you have suffice, or is additional protection needed? While a drysuit could certainly make diving in the late fall and wintertime easier, they do require additional trainings and skills. This of course varies by location, but a wetsuit may be a more useful year-round option.

Made of neoprene, wetsuits keep divers warm by providing an insulating layer made of thousands of tiny air-filled bubbles. The thicker the suit, the warmer it will be.

In colder water, accessories like hoods and gloves may become necessities. Hoods can either be pulled over the head and fit snugly around the wearer’s neck or have a chin strap, leaving the neck exposed. Purchase the hood that works best for you and your diving environment.

Neoprene gloves will keep your digits warm. Look for good seam construction, palm grips and a pair that fit your hand size. Like wetsuits, hoods and gloves come in a variety of thicknesses, so be sure to shop around.

Don’t forget that changing your gear may change your buoyancy. Neoprene is very buoyant, so the thicker the wetsuit, the more it will float. Accommodate this properly with the right amount of weight. Do a weight check to confirm you’re weighted properly.

If possible, start with a few easy, shallow dives when diving with new gear. Accidents can be avoided by familiarizing yourself with all your equipment. And as you do so, also practice a few basic dive skills such as clearing your mask or handling a free-flowing regulator to ensure you’re comfortable doing all these things in cold water. The environment is much different — especially when that cold water hits your face.

The right equipment will certainly decrease the potential for hypothermia, but heat loss will occur regardless. Be mindful of your dive and duration.

Dive Smart

A major reason to dive in cooler water is the possibility of seeing new-to-you marine life and experiencing a new environment. But as with any dives, you need to plan accordingly. So if experiencing new environments and challenges appeals to you, get the gear you need, be sure your dive accident insurance is up to date, and enjoy a safe dive trip.