Process Safety Information (PSI) is the data foundation of your entire PSM program. Under 29 CFR 1910.119(d), employers must compile comprehensive written information about the hazards of their chemicals, the technology of their processes, and the equipment used before conducting any process hazard analysis. Without complete and accurate PSI, every downstream element of your program is built on an unstable foundation. Ecesis PSM software provides centralized document management to organize and maintain your process safety information.
What OSHA Requires
Under 29 CFR 1910.119(d), employers must compile written process safety information before conducting any PHA. This information must include:
- Chemical hazard information: Toxicity, permissible exposure limits, physical data, reactivity data, corrosivity data, and thermal and chemical stability data for each chemical in the process
- Process technology information: Block flow diagrams or simplified process flow diagrams, process chemistry, maximum intended inventory, safe upper and lower operating limits for temperature/pressure/flow/composition, and consequences of deviations
- Equipment information: Materials of construction, piping and instrument diagrams (P&IDs), electrical classification, relief system design and design basis, ventilation system design, design codes and standards employed, material and energy balances, and safety systems
For existing processes, PSI that is not available must be developed based on process engineering evaluation and the best available data.
Step-by-Step Implementation
Inventory Your Covered Processes and Chemicals
Begin by creating a comprehensive list of every covered process and every highly hazardous chemical involved. For each chemical, document the maximum quantity on site and the specific processes where it is used. This inventory defines the scope of your PSI compilation effort.
Compile Chemical Hazard Data
For each highly hazardous chemical in your covered processes, gather and document:
- Safety Data Sheets (SDSs) for all chemicals, verified as current
- Toxicity information including OSHA PELs, ACGIH TLVs, and IDLH concentrations
- Physical properties: boiling point, vapor pressure, specific gravity, flash point, auto-ignition temperature
- Reactivity data: incompatible materials, conditions to avoid, hazardous decomposition products
- Corrosivity data relevant to process equipment materials of construction
- Thermal and chemical stability data under normal and anticipated abnormal conditions
Organize this information so it can be readily accessed by PHA teams, procedure writers, and employees.
Document Process Technology
For each covered process, develop or gather:
- Process flow diagrams: Block flow diagrams or simplified PFDs showing major equipment, piping, and process flows
- Process chemistry: Description of chemical reactions, including side reactions and runaway reaction potential
- Safe operating limits: Maximum and minimum values for temperature, pressure, flow rates, levels, and compositions, with the technical basis for each limit
- Consequences of deviation: What happens when operating parameters exceed safe limits, including potential for runaway reactions, overpressure, toxic releases, and equipment damage
- Maximum intended inventory: The largest quantity of each chemical expected to be in the process at any point during normal operations
Compile Equipment Information
Equipment documentation is often the most challenging category because it requires locating original design records that may be decades old. For each piece of critical process equipment, compile:
- P&IDs: Current piping and instrument diagrams verified to match the as-built configuration
- Materials of construction: Vessel materials, piping specifications, gasket materials, and their suitability for the chemicals and conditions involved
- Design codes and standards: ASME, API, ANSI, and other codes under which equipment was designed and fabricated
- Relief system information: Relief device type, set pressure, capacity, and the design basis for sizing
- Electrical classification: Area classification drawings showing hazardous (classified) locations per NEC/NFPA 70
- Safety systems: Emergency shutdown systems, interlocks, detection and alarm systems
Establish a PSI Maintenance Program
PSI is not a one-time compilation. It must be kept current as processes change. Establish procedures to:
- Update P&IDs whenever physical changes are made (tie this to your MOC process)
- Review and update SDSs when new versions are issued by manufacturers
- Revise operating limits when process modifications alter safe operating ranges
- Verify equipment information when replacements or modifications occur
- Conduct periodic reviews (typically during PHA revalidation cycles) to verify PSI completeness and accuracy
Common Pitfalls to Avoid
How Software Supports This Element
Ecesis PSM software provides the infrastructure to organize, maintain, and control your process safety information:
- Document management: Centralized, version-controlled storage for P&IDs, SDSs, design specifications, and all PSI documents with built-in approval workflows
- Chemical management: SDS library and chemical inventory management with automatic update notifications when new SDS versions are available
- Mobile access: Field personnel can access PSI through the Ecesis mobile app without needing to locate physical files
- MOC integration: Change management workflows automatically trigger PSI updates when process modifications are approved
Frequently Asked Questions
What if process safety information for existing equipment is not available?
For processes that existed before the PSM standard was published, OSHA allows employers to develop PSI through process engineering evaluation using the best available data. This may include field verification of equipment, metallurgical analysis, or reconstruction of design parameters from operating history.
How current must P&IDs be?
P&IDs must reflect the actual as-built configuration of the process. Any physical change to piping, instrumentation, or equipment should trigger a P&ID update, typically through the management of change process. Many OSHA citations involve P&IDs that do not match what is installed in the field.
Are SDSs sufficient for chemical hazard information?
SDSs are a starting point but may not contain all the information OSHA requires for PSI. You may need to supplement SDS data with additional toxicity data, reactivity information specific to your process conditions, and corrosivity data relevant to your equipment materials of construction.
How should PSI be organized?
Organize PSI by process unit, with each unit having a complete package of chemical data, process technology information, and equipment documentation. A centralized document management system ensures information is readily accessible to PHA teams, operators, maintenance personnel, and auditors.
How often should PSI be reviewed for accuracy?
While OSHA does not specify a review frequency for PSI, best practice is to verify completeness and accuracy during each PHA revalidation cycle (at least every five years), and update individual documents whenever changes occur through the MOC process.
Ecesis PSM Compliance Software
PSM Software
Centralized platform to manage all 14 PSM compliance elements
Management of Change
Submit, route, and approve change requests through defined workflows
Incident Investigation
Report, investigate, and track corrective actions to completion
Training Management
Deliver and track PSM training with comprehension verification
Mechanical Integrity
Schedule inspections, track deficiencies, and manage maintenance
PSM Compliance Calendar
Track deadlines across all 14 elements automatically
