Where gas pressures are reduced in two or more stages, each gas pipeline company must install the necessary regulators and equipment in such a manner as to provide protection between regulator stages. The purpose of this rule is to minimize the potential dangers of failures of one stage of regulator equipment resulting from fire, explosion, or damage of any kind, from adversely affecting the operation of the other stage or stages of regulation. Each gas pipeline company must ensure, when practical to do so, that there is a minimum of fifty feet of separation between regulator stages.