The Sun and My Inflatable Friend (or Foe?)
The energy from the sun makes our Earth work. Without it, we wouldn’t exist. However, that same energy, in the form of heat and ultraviolet (UV) radiation, can do great harm to you and your equipment.
The main things you need to be concerned about with your inflatable boat’s relationship with the sun are overinflation caused by heating of the air in the tubes and material damage from UV radiation.
Sam monitoring the pressure in
the 13' Otter with the K-Pump
Kwik Check Gauge.
It made sense, so we filled the Otter again, in the morning when it was cooler, with a hand pump and put it out in the sun again. The day was cooler, in the lower 80s. Sure enough, the pressure went up to 4.0 psi quite quickly. And, of course, this wasn’t even a true duplication of what typically happens with your inflatable. You inflate it on-shore and then put it in the water. The water is usually colder than the air temperature, so you top it off to get the right psi for on-the-water rigidity. Later in the day, with the sun out, the pressure goes up.
So what’s the safest solution? Get a good pressure gauge, and use it regularly to ensure your boat stays at a safe pressure. The K-Pump Kwik Check Gauge is an excellent one. It fits a wide variety of different valves and holds the pressure taken until the pressure release button is pushed. A safe pressure depends on the construction of your boat and the manufacturer’s recommendation. We recommend 2.5 psi as an operating pressure for NRS boats. This gives you a good, rigid hull that won’t “taco” or buckle in a rapid. Whereas our boats can safely take much higher pressure, we strongly recommend keeping them as close to that pressure as possible. Inflating them to a higher pressure doesn’t give you better performance, so why risk damage from overpressure?
On a hot day, let air out of the tubes when you’re pulled up on shore. And let air out of the various chambers evenly, to avoid putting undue pressure on interior baffles. That’s one of the reasons you need to pack a hand pump with you, even on day trips.
Arthur adjusting boat pressure on a July
Grand Canyon trip.
Protecting Your Eyes and Skin from the Sun