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.
Doctors told Kujawa her son was suffering from the effects of a near drowning, sometimes called secondary drowning. Secondary drowning can happen hours after a swimmer leaves the pool. Often referred to by lifeguards as 'parking lot drowning,' it is rare, but happens, Alison Osinski, water safety expert and president of Aquatic Consulting Services, told CNN in an e-mail.