Still, when an unforgiving wave smashes its way below, all hell and everything else breaks loose. In that terrifying, topsy-turvy darkness, you need a light to find a light, and it's no time to be fumbling through drawers in search of one. We keep several waterproof flashlights on board, and I checked that they were secured in their accessible and designated brackets spaced around the boat. Even these flashlights don't share the same power source. I laid out the battery-powered flashlights, a solar-powered light, and even a magnet-and-coil shake light.
When the barometer drops precipitously, I'll tape a chemical lightstick to the center post of the cabin. No matter the chaos below, this can be easily found, then activated by simply hitting it hard. With no connections, no filaments, and no switches, it won't fail. It provides eight hours of sufficient light to begin the work of medical attention, pumping, and damage assessment.