This is the time of the year where cold water safety needs to be on everyone's mind. While the air temperature is starting to warm the water is still VERY cold. As I write this the water off the Rhode Island coast is between 40-45 degrees. Falling into water this cold can quickly become life threatening.
Some basic facts about hypothermia:
When you first fall into cold water you experience what is called "Cold Shock". This typically happens between 0-2 minutes and includes responses such as hyperventilation, rapid heart rate, high blood pressure and difficulty holding your breath. If you go underwater during this time the hyperventilation will cause you to swallow water and you will drown. The most important thing for you to do during this time is remain calm and control your breathing to prevent this from happening.
How long a person can survive in cold water depends on several factors. The most important factor is water temperature. Let's use the range of water temperatures currently off the Rhode Island coast. In water between 40-50 degrees (F) you can expect to become unconscious between 30-60 minutes and time of survival is generally between 1-3 hours. You can also experience hypothermia in warm water as well. If the water is between 70-80 degrees (F) you can expect to become unconscious between 3-12 hours and time of survival can be as quick as 3 hours.
Certain factors can change these times such as: body size, build, body fat, flotation aides and clothing
Cold water safety:
The first point I want to make is NEVER wear cotton. When wet cotton can no longer insulate and becomes very heavy.
The best thing you can wear is a dry suit. I actually know many people who wear dry suits year round and adjust their undergarments to the current temperatures. This is by far the safest option because like I stated earlier, hypothermia can still occur in very warm water temperatures. Personally, I use a two piece dry suit. The top and bottom connect by rolling the inner tunnels of the top and bottom together. I find a two piece more convenient and is much less expensive. A dry suit will keep you dry but will not keep you warm. You need to make sure you layer underneath your dry suit with warm clothing that is also moisture wicking. Fleece and wool are the most popular materials that people wear with fleece being the best choice. DO NOT WEAR COTTON. Cotton is not moisture wicking and will absorb your sweat making it no longer capable of providing insulation. Adjust the amount of layers accordingly for the temperatures. I will typically wear my two piece dry suit through the spring and the fall.
Some people choose to wear wet suits as they are much cheaper than a dry suit. Wet suits range in thickness with the most popular being 3mm, 5mm and 7mm. The most popular for cold weather kayaking are typically the 5mm and 7mm depending on the current temperatures. When wet your body will heat the water between your skin and the wet suit which is how it keeps you warm. However wet suits are very uncomfortable to wear for long duration's of time and can be very restrictive. They are also non breathable and if you are not in the water you will become very sweaty. However, they are a safe option if you are on a budget.
The next option has been the source of much debate and that is waders. I am not going to get into that debate because there are tons of articles discussing this topic. However, my opinion is that waders are not a safe option for kayaking. There is no way to properly join them to a dry top which means that water will find its way into the waders. Also wading belts will not keep out water if you fall in. Your waders will fill up with cold water and make it very difficult to swim and re-enter your kayak.
Also don't forget to keep your head, feet and hands warm. In very cold weather I will wear a fleece hat, 7mm neoprene boots and neoprene gloves.
ALWAYS WEAR YOUR PFD
No matter what time of the year it is or how cold it is you need to always wear a PFD. As I stated earlier you can quickly go into what is called "cold shock" which will cause drowning and you will eventually become unconscious. A PFD can keep you alive by keeping you above the water during these events. Even during warm weather you can become separated from your kayak if you fall in and you will only be able to tread water for so long. Eventually you will become tired and no longer be able to swim. A PFD will keep you afloat until you are rescued.
Please be safe while on the water and remember no fish is worth your life.