69 kV-230 kV are referred to as âhigh voltageâ and voltages 230 kV-1,100 kV are referred to as âextra high. voltage,â with 1,100 kV also referred to as âultra high voltage.â The emphasis of this guide is on low and. medium voltage distribution systems.
Most manufacturers of umbrella strollers recommend that these strollers should not be used for any infant under 6 months old. This age is set by manufacturers because it is the average age when infants have sufficient strength to sit up and have some head and neck control.
However, parents of individual babies are in the best position to decide when their baby has the physical ability to ride in an umbrella stroller safely. Some infants may have no difficulty when they are as young as 4 months, while others may not be ready to sit up well until they are 7 or even 8 months old.