I’m not sure what is your questions related to… electric water heaters are as safe as the gas water heaters. Depending on the water heater size, it might have one or two heating elements. If one of them fails (usually the bottom one first), it will take much longer to heat-up that tank of water. Each heating element has a small adjustment screw / thermostat with a temperature scale. By turning the screw you will lower or increase the water heater tank output temperature.
Before any attempt to change the temperature, you must TURN OFF the electric water heater power supply! – the thermostat is concealed behind a metal plate, often covered with insulation, and there might be some exposed high voltage wires
It takes just one second to burn your skin with 160F water temperature, 1/2 minute at 130F. The maximum water temperature setting suggested by the Consumer Product Safety Commission is 120F (about 10 minutes of exposure will give you 3rd degree burns). 110F is safe but not hot enough for some of us… Be careful.
You can check - water heater inspection - post for more information.