When cold water diving, having the hood fitted for your dive will make the difference between having an enjoyable dive, experiencing the underwater world and being a good buddy, or experiencing a very short dive along with the pain of brain freeze and potentially experiencing signs of Hypothermia.
Many factors affect which cold water dive hood you should use for your dive conditions. One of those factors is the temperature you are anticipating experiencing. In addition, the hood’s fit and the hood’s constructions are all significant factors in picking a cold water dive hood.
How to pick a cold water dive hood.
– If you plan on diving water colder than 5-12 degrees Celsius, having a dive hood with a minimum of 5 mm of neoprene should keep you warm. For a 20-30 minutes dive within recreational depth limits, you are not too sensitive to the cold.
– Diving conditions between 5-0 degrees having a dive hood that is 7- 10 mm should keep you warm again depending on the duration of your dive and within recreational limits.
Having a bib on your hood is essential If you are diving a wetsuit; however, if you are diving a drysuit with a warm collar, you can tuck the hoods bib under the collar. Otherwise, having a bib-less hood on a dry suit can work fine, but you may want to consider a neoprene neck seal ( warmer than silicon). Finally, some drysuit just isn’t set up to have a bibbed hood.
Let’s look at the details of choosing a cold water dive hood that will keep you warm, be comfortable and hopefully, last you a long time. My goal is to save you some money by not buying several before knowing what works for you.
The thickness of a cold water hood
The thickness and quality of the neoprene give it its thermal properties, which help the hood keep your head warm. The way a neoprene dive hood works is that the neoprene provides insulation from the cold water environment, but it works a little counter-intuitively. The hood still lets water in around your head, but with a proper fit, water will mostly just surround your head, and the heat in your head is what warms the water and the neoprene-provides insulation, and tada you have a warm head in cold water.
Neoprene, what to look for?
A functional dive hood is made of quality materials, and not all neoprene is the same. Neoprene gets its thermal properties because the rubber material will trap lots of air bubbles when manufactured. The more air bubbles, the more thermal insulation the hood will have. Cheaper off-brand neoprene will see a lot more rubber and barely any bubbles, but quality neoprene is characterized by having more bubbles trapped in the neoprene. Some brands will layer the neoprene with different thicknesses for better comfort and good thermal protection.
The air bubbles in the neoprene provide a lot of insulation in neoprene. However, when one dives deeper, the pressure will collapse these bubbles, thus compressing the neoprene and losing its thermal properties. Several brands have worked with neoprene manufacturing to curb this negative quality of some neoprenes.
There are even companies like KO1 cold water dive gear, whose neoprene is made in Japan, where they fill the bubbles in the neoprene with a different gas than air for even better thermal properties. These are just some things to think about when selecting a cold water dive hood.
Dive hoods come with a wide variety of thicknesses and configurations. Warmer waters rarely require a dive hood, but some people are a little more sensitive to the cold than others.
Hoods come in a variety of configurations. For example, you may see a 3 mm and a 5 mm type hood with a strap at the chin. Unfortunately, these don’t provide nearly enough thermal or temperature protection in cold water, mainly because the neoprene is thin, and an open chins strap doesn’t allow much opportunity for water to stay trapped in the hood for your body to warm up.
Good cold water dive hoods will start at 5mm and go up 8mm and 10 mm and will possibly have 1-2 inch sections of neoprene that may be a little thinner rims around your face. This allows one to trim the hood around your face to accommodate your mask. In addition, you can cut it away from your lips; this will help relieve any jaw fatigue.
Depending on how sensitive you are to the cold and the variety of temp you will encounter on your dives. I regularly dive in southern Ontario Canada, water temps here in the summer may get up to 12 C, but in the winter, water temps are 0C which is somewhat of a swing in temperature in the water. Most of my dive sites will have a thermocline which puts most of my dives at1-5 degrees C even in the summer.
Something to consider is the outdoor temperature; if I am diving in August on a shore dive, and it’s 35C outside while gearing up, even with the water being 3-5C, I’ll use my 5mm hood simply because if I have my drysuit on and my hood. I have to walk just 100 feet to the water. I’ll be sweating and experiencing far too much heat than I am comfortable before starting the dive. In the winter, where it may be -1C outdoors while gearing up, it’s nice to put an 8-10mm hood on; not only will it keep you warm before the dive, but it continues to provide the thermal temperature I like during the dive. If I did that with a 5mm hood, I would be cold before the dive started, and if I used 8mm during the summer, it makes me sweat and get far too hot for my comfort.
This is all determined by personal preference but sharing the idea of the surface temperature affects the hood selection sometimes too because all the water we dive up here is cold, but the surface temperature can vary greatly.
How should the dive hood fit?
Neoprene provides insulations from the water and works best when a small layer of water surrounds your head which will feel cold for the first 30 seconds to a minute ( click here for our cold water diving blog). Still, once your body temperature warms the small amount of water, you have a second thermal layer: the neoprene and the other the small amount of water. The hood shouldn’t be tight around your head and neck for this to happen. You shouldn’t have to wrestle the hood off of you; it should be a stung fit. A too big or loose hood will allow too much water to fill the hood and leave the hood continually, thus not allowing the neoprene to provide thermal barriers to cold water, and your head can’t warm the water.
The face rim of the hood and the bib can be trimmed to fit you better. Cut The edge around your face if it is too big and goes over your lower lips or makes it difficult for you to move your jaw. It can also be cut if it crowds your field of view and makes it impossible to put your mask on underwater.
The bib can be trimmed to make it easier to place in your wetsuit. Some bibs are too large and create a material ball under the wetsuit collar. The same can happen on a dry suit when a bib is not trimmed. Remember, it’s always better to start by cutting small amounts till you get to the fit that works best for you, maybe even over a few dives. Most cold-water dive hoods should have a small hole or venting system in the top of the hood to let air trapped in the hood get out.
There are dive hoods on the market with zippers along the back. Sometimes, this can help find the right fit yet still allow it to come off quickly at the end of the dive.
To bib or not to bib on your dive hood, that is the question?
If you are diving in a wet suit, you will want a cold water dive hood with a bib on it. It makes the whole wet suit system work better. If everything is fitted correctly, some of the water from your torso will move up into the hood and from the hood to the torso.
Whether you dive with a bib or not, diving in a dry suit is up to your comfort of dawning your equipment and your tolerance to the cold, the kind of drysuit you have. Having a bib for some divers makes it challenging to dawn their equipment by themselves, requiring you to ask your dive buddy to tuck your bib into your warm drysuit collar. Some people are warm enough in their drysuit that having a bibbed hood can make it too warm for them during the dive, even in cold water, or they find it uncomfortable diving with the extra material around their neck in the drysuit. And finally, some drysuits don’t have a warm collar for stowing the bib from the hood, which leads you to need a bibless cold water dive hood.
As you can see, a well-fitted hood can do a lot more than just make you look silly before a dive. In the future, I would like to test some hoods against each other in similar conditions to see which performs better in similar situations. Until then, I hope this article answers some of your questions, saves you some money and helps you Dive to Escape!
Recommendations
3-6mm
7-10mm
Thanks for reading. Check out some of our other cold-water dive articles by clicking here.