A kayaker and his dog were rescued after their kayak overturned, but a second paddler drowned after slipping out of a personal flotation device in cold, rough water.

A. The old rule of thumb was to wear immersion protection if the sum of the air and water temperatures combined was less than 120°F (49°C). Nowadays, cold-water researchers advise dressing for the water temperature alone, and treating water below 70°F (21°C) with caution.

Immersion protection, like drysuits and wetsuits, help delay hypothermia and protect against cold shock response, which is caused by the sudden lowering of skin temperature upon immersion. Cold shock can cause involuntary gasping and hyperventilation, a spike in heart rate and blood pressure, and panic for many. Cold shock can kill in just seconds.

If the cold shock doesn’t get you, there is the 1-10-1 principle of cold water immersion. Experts recommend spending one minute recovering and getting breathing under control. Then a swimmer may have 10 minutes of meaningful movement to self-rescue. Swim failure follows, and then drowning if a person is not wearing a PFD. Editor-in-Chief Kaydi Pyette waded into the topic in her column titled “The Scary Truth About Surviving Capsizing In Cold Water,” but the quick and dirty answer is, if the water temp is below recommended, suit up.

Have a question? Reply to this email to submit your paddling-related question, and we’ll do our best to answer it in an upcoming newsletter.

When a solo canoeist capsized into frigid water, he thought he could swim to shore. He quickly realized he wasn’t going to make it. Find out how he survived and the lessons every early-season paddler should know.