If the temperature falls below about 32 °C, hypothermia can result, and temperatures above 45 °C can cause burn injury to the diver. The diver may not notice a gradual change in inlet temperature, and in the early stages of hypo- or hyperthermia, may not notice the deteriorating condition.[14] The suit is loose fitting to allow unimpeded water flow. This causes a large transient volume of water (13 to 22 litres) to be held in the suit, which can impede swimming due to the added inertia.[14] When controlled correctly, the hot water suit is safe, comfortable and effective, and allows the diver adequate control of thermal protection, however hot water supply failure can be life-threatening.[14]