This standard describes the specifications and general principles recommended for piping systems for gaseous (Type I) or liquid (Type II) hydrogen. The standard addresses both low and high pressure hydrogen piping systems onsite from the point where hydrogen enters the distribution piping (the battery limits of the hydrogen storage system) to the point of use. For the purposes of this standard, high pressure is defined as gaseous hydrogen at service pressures equal to or greater than 3000 psig (20 680 kPa).