Home › PSM Elements › Process Safety Information
29 CFR 1910.119(d)

Element 2: Process Safety Information

You cannot manage what you don't know. PSI is the foundation every other PSM element builds on.

$4,000-$15,625
Penalty Range
Very Common
Citation Frequency
#3 Most Cited
PSM Ranking
Element Overview

What Is Process Safety Information Under PSM?

Process Safety Information is the foundation of PSM. Before you can analyze hazards, write procedures, or train workers, you need accurate, complete, and up-to-date information about the chemicals in your process, the technology of the process, and the equipment used in the process. OSHA's 1910.119(d) lays out exactly what that information must include.

PSI is not a one-time documentation exercise. P&IDs get updated. Equipment gets modified. Processes change. Every time a management of change is approved, PSI must be updated to reflect the new reality. Outdated P&IDs are one of the most commonly cited PSI deficiencies — and one of the most dangerous, because operators and emergency responders may rely on them in a crisis.

The three pillars of PSI are chemical hazard information (Safety Data Sheets, reactivity data, flammability limits), technology information (process flow diagrams, design intents, safe operating limits), and equipment information (materials of construction, relief system design, electrical classification, ventilation design). All three must be completed before a PHA is conducted.

Regulatory Text

What the Standard Actually Requires

The employer shall complete a compilation of written process safety information before conducting any process hazard analysis required by the standard. The compilation of written process safety information is to enable the employer and the employees involved in operating the process to identify and understand the hazards posed by those processes involving highly hazardous chemicals.— 29 CFR 1910.119(d)(1)
  • 1
    Chemical Hazard Information — Toxicity, permissible exposure limits, physical data, reactivity data, corrosivity, thermal/chemical stability, and hazardous effects of inadvertent mixing.
  • 2
    Process Technology Information — Block flow diagram or simplified process flow diagram, process chemistry, maximum intended inventory, safe upper and lower limits, consequences of deviations.
  • 3
    Equipment Information — Materials of construction, P&IDs, electrical classification, relief system design basis, ventilation design, design codes and standards, material and energy balances, safety systems.
  • 4
    Pre-PHA Completion — All PSI must be compiled and complete before conducting a process hazard analysis.
  • 5
    Trade Secret Exception — Even if information is a trade secret, it must still be available to employees involved in PSM activities.
Compliance Failures

Common Violations OSHA Cites

These are the deficiencies inspectors most frequently document in Process Safety Information programs. Each can represent a separate citation.

Frequently Cited Violations

  • P&IDs not updated to reflect current as-built conditions after modifications
  • Missing or incomplete relief system design documentation
  • No documentation of safe upper and lower operating limits with consequences of deviation
  • Chemical hazard information absent or outdated for highly hazardous chemicals in process
  • Equipment materials of construction not documented
  • PSI not available to employees involved in process operation or emergency response

What Inspectors Look For

  • Field-walking the process and comparing actual equipment configuration against P&IDs
  • Requesting the last three MOC packages and verifying PSI was updated as required
  • Asking operators where they would find safe operating limits and consequences of deviation
  • Reviewing relief device documentation to confirm design basis matches current process conditions
Real-World Impact

Consequences of Process Safety Information Failures

Inaccurate PSI has contributed to numerous major incidents. When P&IDs do not reflect actual process configuration, workers cannot safely isolate equipment, emergency responders cannot identify release pathways, and PHAs analyze hypothetical processes rather than actual ones. The CSB's investigation of the Texas City refinery disaster identified outdated engineering documentation as a key contributing factor.

Penalty Exposure — Process Safety Information

OSHA penalty range for Process Safety Information violations: $4,000-$15,625 per violation. PSI citations are frequently classified as serious or willful when P&IDs are significantly out of date or when PSI was not complete before PHAs were conducted. Penalties can exceed $15,000 per instance for willful violations, and each deficient element of PSI may constitute a separate violation.

Documentation Requirements

Documents Your PSI Program Needs

An OSHA compliance inspection for Process Safety Information will typically request the following. Gaps in any of these areas may result in citations.

Required Documentation

  • Process Safety Information binder (chemicals, technology, equipment)
  • Current as-built P&IDs
  • Relief system design basis documentation
  • Safe operating limits with consequences of deviation
  • Materials of construction records
  • Equipment design codes and standards
OSHA Letter of Interpretation

Related LOI Guidance

OSHA has clarified these specific questions about the Process Safety Information element through official Letters of Interpretation:

Are P&IDs Required to Be Current As-Built? What Documentation Is Required for Relief Systems? Do Connected Vessels Require Separate PSI? Does Instrument Change Require MOC and PSI Update?

Get Process Safety Information Documents — Ready to Use

SafeGuard PSM provides OSHA-aligned Process Safety Information procedures, templates, and checklists that you can implement today. Written by PSM professionals. Formatted for actual field use.

Browse the Document Library →