Screw clamps. Screw clamps are types which use a screw mechanism to adjust the jaws and clamp a workpiece in place. The types which are found in the screw clamp category include G clamps (also known as C clamps), F clamps, edging clamps, wooden hand screw clamps and rack clamps.
Dry drowning usually happens soon after exiting the water, but with secondary drowning, there can be a delay of up to 24 hours before the person shows signs of distress. Both can cause trouble breathing and, in worst-case scenarios, death.
Death by asphyxiation (because of secondary drowning) can actually occur up to 72 hours after a near-drowning incident. The 72 hour time frame exists because that is how long it can take the body to recognize a problem and create a solution for it. Freshwater may be more dangerous than saltwater in secondary drowning.