Years ago, we had a near sinking on one of our test boats due to a failed 0-ring on the speed sensor through-hull installed by a previous owner. The sinking would be attributed to the failure of an O-ring, and because the sinking was consequential to the failure of a maintenance item and we did not have consequential loss coverage, the insurance would not have paid the claim. In fact, most boats sink at the dock due to failure of some minor item, and most policies don't cover the damage consequential to the failure of that item. In other words, we are sailing bare, without insurance coverage for our most serious exposure.
As ventilation experts explore ways to make indoor spaces safer during the COVID-19 pandemic, we became curious about ventilation in our boats. As it turns out, where we install our exhaust or intake vents (portlight, hatch, or cowl) is just as important as what type of vent we use. Just as we can use the suction on the leeward side of a sail to pull the boat forward, we can use pressure differentials in the air surrounding the cabin to maximize the ventilation. Understanding the pressure differentials created by the flow of air over our boat’s deck is vital to the success of any passive ventilation scheme.