Enforcement Guidance documents are available to clarify PHMSA's enforcement authority by identifying and summarizing precedent, including those from interpretations, advisory bulletins, final orders, and decisions on petitions for reconsideration.  The material contained in these documents describe the practices used by PHMSA personnel in undertaking their compliance, inspection, and enforcement activities.  This guidance facilitates improved enforcement consistency and is particularly helpful when precedence exists for clarifying performance-based requirements.