An interior door does not have to withstand extreme weather changes. Interior and exterior doors are not the same product sold under different labels. The construction of each is different, with exterior doors given special treatment to stand up to the elements and frequent use.
The charging of lead-acid batteries can be hazardous. However, many workers may not see it that way since it is such a common activity in many workplaces. The two primary risks are from hydrogen gas formed when the battery is being charged and the sulfuric acid in the battery fluid.
individual CELLS are connected together 'in series' to make batteries of either 12 volt (6 cells) or 24 volt (12 cells). Although a battery is called a '12 volt' battery, its voltage varies from about 12.6 volts down to. 10 volts when it is discharging and can rise to 15 or 16 volts during charging. It is very. important, however, to limit the maximum battery voltage during charging otherwise the. battery will be damaged.