Source: This is the full text of 29 CFR § 1910.119 as published in the Code of Federal Regulations, Title 29 (Labor), Part 1910 (Occupational Safety and Health Standards), Subpart H (Hazardous Materials). The standard was promulgated on February 24, 1992 (57 FR 6356) and became effective May 26, 1992.
This page reproduces the regulatory text verbatim. The "What this means" annotations are editorial explanations and do not constitute legal advice or official OSHA guidance.
Application
§ 1910.119(a)(a) Application. This section applies to the following:
(1) A process which involves a chemical at or above the specified threshold quantities listed in appendix A to this section;
(2) A process which involves a flammable liquid or gas (as defined in § 1910.106(a)(2) of this part) on site in one location, in a quantity of 10,000 pounds (4535.9 kg) or more except for:
(i) Hydrocarbon fuels used solely for workplace consumption as a fuel (e.g., propane used for comfort heating, gasoline for vehicle refueling), if such fuels are not a part of a process containing another highly hazardous chemical covered by this standard;
(ii) Flammable liquids stored in atmospheric tanks or transferred which are kept below their normal boiling point without benefit of chilling or refrigeration.
(a)(3) This section does not apply to:
(i) Retail facilities;
(ii) Oil or gas well drilling or servicing operations; or
(iii) Normally unoccupied remote facilities.
PSM coverage is triggered in two ways: (1) you have a listed highly hazardous chemical (from Appendix A) at or above its threshold quantity, or (2) you have 10,000 lbs or more of any flammable liquid or gas on site in one location.
The flammable exemptions are narrow. Propane used just for heating a building is exempt. Atmospheric storage tanks holding flammable liquids at ambient temperature are exempt. But if that same propane or gasoline is part of a process that also uses a listed HHC, the exemption disappears.
Three categories are always exempt: retail facilities (gas stations, hardware stores), oil and gas well drilling/servicing operations, and normally unoccupied remote facilities (unmanned pipeline compressor stations, etc.).
See Am I Covered? for an interactive walkthrough of the coverage analysis.
Definitions
§ 1910.119(b)(b) Definitions.
Atmospheric tank means a storage tank which has been designed to operate at pressures from atmospheric through 0.5 p.s.i.g. (pounds per square inch gauge, 3.45 Kpa).
Boiling point means the boiling point of a liquid at a pressure of 14.7 pounds per square inch absolute (p.s.i.a.) (760 mm.). For the purposes of this section, where an accurate boiling point is unavailable for the material in question, or for mixtures which do not have a constant boiling point, the 10 percent point of a distillation performed in accordance with the Standard Method of Test for Distillation of Petroleum Products, ASTM D-86-62, which is incorporated by reference as specified in § 1910.6, may be used as the boiling point of the liquid.
Catastrophic release means a major uncontrolled emission, fire, or explosion, involving one or more highly hazardous chemicals, that presents serious danger to employees in the workplace.
Facility means the buildings, containers or equipment which contain a process.
Highly hazardous chemical means a substance possessing toxic, reactive, flammable, or explosive properties and specified by paragraph (a)(1) of this section and in appendix A to this section.
Hot work means work involving electric or gas welding, cutting, brazing, or similar flame or spark-producing operations.
Normally unoccupied remote facility means a facility which is operated, maintained or serviced by employees who visit the facility only periodically to check its operation and to perform necessary operating or maintenance tasks. No employees are permanently stationed at the facility. Facilities meeting this definition are not contiguous with, and must be geographically remote from, all other buildings, processes or persons.
Process means any activity involving a highly hazardous chemical including any use, storage, manufacturing, handling, or the on-site movement of such chemicals, or combination of these activities. For purposes of this definition, any group of vessels which are interconnected and separate vessels which are located such that a highly hazardous chemical could be involved in a potential release shall be considered a single process.
Replacement in kind means a replacement which satisfies the design specification.
Trade secret means any confidential formula, pattern, process, device, information or compilation of information that is used in an employer's business, and that gives the employer an opportunity to obtain an advantage over competitors who do not know or use it. Appendix D (the U.S. Army regulation) to § 1910.1200 sets out the criteria to be used in evaluating trade secrets.
These definitions carry significant compliance weight. Several are worth calling out:
- Process is defined very broadly — it includes any activity involving an HHC (use, storage, manufacture, handling, movement), and interconnected vessels or vessels close enough to be involved in a release are treated as a single process. This prevents facilities from artificially fragmenting processes to stay below TQ thresholds.
- Replacement in kind is critically important for Management of Change. A replacement that exactly meets the original design specification is not a "change" under PSM. Anything outside that specification — different material, different rating, different size — triggers an MOC review.
- Catastrophic release defines the event PSM is designed to prevent: a major uncontrolled emission, fire, or explosion that presents serious danger to workers. This frames the entire purpose of the standard.
- Hot work covers more than welding — any spark-producing or flame operation qualifies, including cutting, brazing, and grinding.
Employee Participation
§ 1910.119(c)(c) Employee participation.
(1) Employers shall develop a written plan of action regarding the implementation of the employee participation required by this paragraph.
(2) Employers shall consult with employees and their representatives on the conduct and development of process hazards analyses and on the development of the other elements of process safety management in this standard.
(3) Employers shall provide to employees and their representatives access to process hazard analyses and to all other information required to be developed under this standard.
Employee participation is often treated as a checkbox element, but it carries real teeth. The three requirements are: (1) a written plan describing how you'll involve employees, (2) actual consultation with employees and their representatives during PHA development and other PSM elements, and (3) employee access to PHAs and all other PSM documentation.
OSHA expects more than a signature on a participation plan — inspectors look for evidence that employees actually participated in PHA studies, reviewed procedures, and were consulted during MOC reviews. A PHA conducted entirely by outside consultants with no employee involvement is a common citation.
"Representatives" includes union representatives where applicable, but also any employee who represents their coworkers in safety matters.
Process Safety Information
§ 1910.119(d)(d) Process safety information. In accordance with the schedule set forth in paragraph (e)(1) of this section, 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. This process safety information shall include information pertaining to the hazards of the highly hazardous chemicals used or produced by the process, information pertaining to the technology of the process, and information pertaining to the equipment in the process.
(1) Information pertaining to the hazards of the highly hazardous chemicals in the process. This information shall consist of at least the following:
(i) Toxicity information;
(ii) Permissible exposure limits;
(iii) Physical data;
(iv) Reactivity data;
(v) Corrosivity data;
(vi) Thermal and chemical stability data; and
(vii) Hazardous effects of inadvertent mixing of different materials that could foreseeably occur.
(2) Information pertaining to the technology of the process shall include, as appropriate, at least the following:
(i) A block flow diagram or simplified process flow diagram (see appendix B to this section);
(ii) Process chemistry;
(iii) Maximum intended inventory;
(iv) Safe upper and lower limits for such items as temperatures, pressures, flows or compositions; and
(v) An evaluation of the consequences of deviations, including those affecting the safety and health of employees.
(3) Information pertaining to the equipment in the process shall include, as appropriate, at least the following:
(i) Materials of construction;
(ii) Piping and instrument diagrams (P&ID's);
(iii) Electrical classification;
(iv) Relief system design and design basis;
(v) Ventilation system design;
(vi) Design codes and standards employed;
(vii) Material and energy balances for processes built after June 21, 1999; and
(viii) Safety systems (e.g., interlocks, detection or suppression systems).
(4) The employer shall document that equipment complies with recognized and generally accepted good engineering practices.
(5) For existing equipment designed and constructed in accordance with codes, standards, or practices that are no longer in general use, the employer shall determine and document that the equipment is designed, maintained, inspected, tested, and operating in a safe manner.
PSI is the foundation of the entire PSM program — it must be completed before a PHA can be conducted. Think of PSI as the technical dossier on your process: what chemicals you have and how dangerous they are, how the process works, and how the equipment is designed.
Three categories of PSI are required:
- Chemical hazard data — toxicity, physical properties, reactivity, stability, corrosivity, and hazardous mixing scenarios. SDS sheets are often used but may not be sufficient on their own.
- Process technology data — block flow diagrams or PFDs, process chemistry, maximum inventory, safe operating limits (temperature, pressure, flow, composition), and consequences of deviations from those limits.
- Equipment data — P&IDs (must reflect current field conditions), materials of construction, electrical classification, relief system design basis, safety systems. P&IDs are the most commonly cited PSI deficiency — they must be current and accurate.
The "RAGAGEP" requirement (paragraph d(4)) requires documenting that equipment complies with Recognized and Generally Accepted Good Engineering Practices. For older equipment no longer built to current codes, you must document that it's still safe despite the code gaps.
Process Hazard Analysis
§ 1910.119(e)(e) Process hazard analysis.
(1) The employer shall perform an initial process hazard analysis (hazard evaluation) on processes covered by this standard. The process hazard analysis shall be appropriate to the complexity of the process and shall identify, evaluate, and control the hazards involved in the process. Employers shall determine and document the priority order for conducting process hazard analyses based on a rationale which includes such considerations as extent of the process hazards, number of potentially affected employees, age of the process, and operating history of the process. The process hazard analysis shall be conducted as soon as possible.
(2) The employer shall use one or more of the following methodologies that are appropriate to determine and evaluate the hazards of the process being analyzed:
(i) What-If;
(ii) Checklist;
(iii) What-If/Checklist;
(iv) Hazard and Operability Study (HAZOP);
(v) Failure Mode and Effects Analysis (FMEA);
(vi) Fault Tree Analysis; or
(vii) An appropriate equivalent methodology.
(3) The process hazard analysis shall address:
(i) The hazards of the process;
(ii) The identification of any previous incident which had a likely potential for catastrophic consequences in the workplace;
(iii) Engineering and administrative controls applicable to the hazards and their interrelationships such as appropriate application of detection methodologies to provide early warning of releases (acceptable detection methods might include process monitoring and control instrumentation with alarms, and detection hardware such as hydrocarbon sensors);
(iv) Consequences of failure of engineering and administrative controls;
(v) Facility siting;
(vi) Human factors; and
(vii) A qualitative evaluation of a range of the possible safety and health effects of failure of controls on employees in the workplace.
(4) The process hazard analysis shall be performed by a team with expertise in engineering and process operations, and the team shall include at least one employee who has experience and knowledge specific to the process being evaluated. Also, one member of the team must be knowledgeable in the specific process hazard analysis methodology being used.
(5) The employer shall establish a system to promptly address the team's findings and recommendations; assure that the recommendations are resolved in a timely manner and that the resolution is documented; document what actions are to be taken; complete actions as soon as possible; develop a written schedule of when these actions are to be completed; communicate the actions to operating, maintenance and other employees whose work assignments are in the process and those who could be affected by the recommendations or actions.
(6) At least every five (5) years after the completion of the initial process hazard analysis, the process hazard analysis shall be updated and revalidated by a team meeting the requirements in paragraph (e)(4) of this section, to assure that the process hazard analysis is consistent with the current process.
(7) Employers shall retain process hazard analyses and updates or revalidations for each process covered by this section, as well as the documented resolution of recommendations described in paragraph (e)(5) of this section for the life of the process.
The PHA is the core hazard identification and risk evaluation activity of PSM. It must be completed by a qualified team using one of the six listed methodologies (or equivalent). HAZOP is the most common methodology for complex continuous processes; What-If/Checklist is often used for simpler batch or storage operations.
Team composition matters. The team must include at least one person with hands-on experience with the specific process being studied, and one person trained in the methodology being used. PHAs conducted entirely by outside consultants without process-knowledgeable operators on the team are a citation.
The 5-year revalidation clock is strict. Once a PHA is completed, it must be updated and revalidated at least every five years. A common citation is an overdue revalidation — the clock starts from the date of the initial PHA or the last revalidation, not from the study's scheduled date. The CCPS Guidelines for Process Hazard Analysis Revalidations is the field reference for scoping, methodology selection, and documentation.
Recommendations must be resolved. A PHA that generates recommendations but doesn't track their resolution is a citation. You need a written schedule, documented completion, and communication to affected employees. Open recommendations sitting unresolved for years are a red flag in any OSHA inspection.
PHAs must be retained for the life of the process — including all updates, revalidations, and documented recommendation resolutions.
Operating Procedures
§ 1910.119(f)(f) Operating procedures.
(1) The employer shall develop and implement written operating procedures that provide clear instructions for safely conducting activities involved in each covered process consistent with the process safety information and shall address at least the following elements:
(i) Steps for each operating phase:
(A) Initial startup;
(B) Normal operations;
(C) Temporary operations;
(D) Emergency shutdown including the conditions under which emergency shutdown is required, and the assignment of shutdown responsibility to qualified operators to ensure that emergency shutdown is executed in a safe and timely manner;
(E) Emergency Operations;
(F) Normal shutdown; and
(G) Startup following a turnaround, or after an emergency shutdown.
(ii) Operating limits:
(A) Consequences of deviation; and
(B) Steps required to correct or avoid deviation.
(iii) Safety and health considerations:
(A) Properties of, and hazards presented by, the chemicals used in the process;
(B) Precautions necessary to prevent exposure, including engineering controls, administrative controls, and personal protective equipment;
(C) Control measures to be taken if physical contact or airborne exposure occurs;
(D) Quality control for raw materials and control of hazardous chemical inventory levels; and
(E) Any special or unique hazards.
(iv) Safety systems and their functions.
(2) Operating procedures shall be readily accessible to employees who work in or maintain a process.
(3) The operating procedures shall be reviewed as often as necessary to assure that they reflect current operating practice, including changes that result from changes in process chemicals, technology, and equipment, and changes to facilities. The employer shall certify annually that these operating procedures are current and accurate.
(4) The employer shall develop and implement safe work practices to provide for the control of hazards during operations such as lockout/tagout; confined space entry; opening process equipment or piping; and control over entrance into a facility by maintenance, contractor, laboratory, or other support personnel. These safe work practices shall apply to employees and contractor employees.
Operating procedures must cover all seven phases of operation — not just normal operations. The startup-after-shutdown and emergency shutdown procedures are particularly important and often missing or inadequate. Procedures must be consistent with the PSI (if your safe operating limits changed, the procedures must reflect that).
The annual certification requirement (paragraph f(3)) is one of the most commonly missed. Each year, someone must certify in writing that all operating procedures are current and accurate. This is a dated, signed certification — not just a review. Many facilities fall behind on this.
Accessibility matters. Procedures stored only in a supervisor's office or behind a login that operators don't use don't meet the "readily accessible" standard. Procedures should be physically available at the point of use.
Safe work practices (paragraph f(4)) includes LOTO, confined space entry, and opening process equipment — these must be written and apply to both employees and contractors.
Training
§ 1910.119(g)(g) Training.
(1) Initial training.
(i) Each employee presently involved in operating a process, and each employee before being involved in operating a newly assigned process, shall be trained in an overview of the process and in the operating procedures as specified in paragraph (f) of this section. The training shall include emphasis on the specific safety and health hazards, emergency operations including shutdown, and safe work practices applicable to the employee's job tasks.
(ii) In lieu of initial training for those employees already involved in operating a process on May 26, 1992, an employer may certify in writing that the employee has the required knowledge, skills, and abilities to safely carry out the duties and responsibilities as specified in the operating procedures.
(2) Refresher training. Refresher training shall be provided at least every three (3) years, and more often if necessary, to each employee involved in operating a process to assure that the employee understands and adheres to the current operating procedures of the process. The employer, in consultation with the employees involved in operating the process, shall determine the appropriate frequency of refresher training.
(3) Training documentation. The employer shall ascertain that each employee involved in operating a process has received and understood the training required by this paragraph. The employer shall prepare a record which contains the identity of the employee, the date of training, and the means used to verify that the employee understood the training.
PSM training requirements apply to employees who operate covered processes. Training must cover the process overview, operating procedures, specific hazards, emergency operations including shutdown, and safe work practices.
The 3-year refresher clock is a hard minimum — OSHA inspectors will ask for training records and check dates. If the refresher is overdue for any operator, that's a citable condition. The standard says "more often if necessary," so if your process changes significantly, refresher training may be required sooner.
Understanding must be verified. A sign-in sheet isn't enough. You must document that the employee understood the training — this typically means a written test, practical demonstration, or structured evaluation. The record must show the employee's name, training date, and how understanding was verified.
Training records should be retained for the duration of employment and typically a period beyond, as OSHA may request them during inspections covering incidents or near-misses.
Contractors
§ 1910.119(h)(h) Contractors.
(1) Application. This paragraph applies to contractors performing maintenance or repair, turnaround, major renovation, or specialty work on or adjacent to a covered process. It does not apply to contractors providing incidental services which do not influence process safety, such as janitorial work, food and drink services, laundry, delivery or other supply services.
(2) Employer responsibilities. The employer, when selecting a contractor, shall obtain and evaluate information regarding the contractor's safety performance and programs. The employer shall:
(i) Inform contract employees of the known potential fire, explosion, or toxic release hazards related to the contractor's work and the process;
(ii) Explain to contract employees the applicable provisions of the emergency action plan required by paragraph (n) of this section;
(iii) Develop and implement safe work practices consistent with paragraph (f)(4) of this section, to control the entrance, presence and exit of contract employees in covered process areas;
(iv) Periodically evaluate the performance of contract employers in fulfilling their obligations as specified in paragraph (h)(3) of this section; and
(v) Maintain a contract employee injury and illness log related to the contractor's work in process areas.
(3) Contract employer responsibilities. The contract employer shall:
(i) Assure that each contract employee is trained in the work practices necessary to safely perform his/her job;
(ii) Assure that each contract employee is instructed in the known potential fire, explosion, or toxic release hazards related to his/her job and the process, and the applicable provisions of the emergency action plan;
(iii) Document that each contract employee has received and understood the training required by this paragraph. The contract employer shall prepare a record which contains the identity of the contract employee, the date of training, and the means used to verify that the employee understood the training;
(iv) Assure that each contract employee follows the safety rules of the facility including the safe work practices required by paragraph (f)(4) of this section; and
(v) Advise the employer of any unique hazards presented by the contract employer's work, or of any hazards found by the contract employer's work.
PSM contractor requirements create obligations on both sides — the host employer (your facility) and the contract employer (the contractor's company). This is a dual-responsibility framework.
Host employer obligations: You must evaluate contractor safety performance before hiring (documented), inform contractors of known hazards, explain your emergency action plan, control contractor access to process areas, periodically evaluate contractor performance, and maintain a contractor injury/illness log for process area work.
Contractor employer obligations: The contractor must train their own employees, document that training (with verification of understanding), ensure compliance with your facility's safety rules, and notify you of any unique hazards they bring to the job or discover during their work.
The injury/illness log requirement is frequently overlooked — you must track injuries and illnesses among contractor employees working in your process areas, separate from your own OSHA 300 log.
The "incidental services" exemption is narrow — janitorial, food service, delivery. Any contractor whose work could affect process safety is covered.
Pre-Startup Safety Review
§ 1910.119(i)(i) Pre-startup safety review.
(1) The employer shall perform a pre-startup safety review for new facilities and for modified facilities when the modification is significant enough to require a change in the process safety information.
(2) The pre-startup safety review shall confirm that prior to the introduction of highly hazardous chemicals to a process:
(i) Construction and equipment is in accordance with design specifications;
(ii) Safety, operating, maintenance, and emergency procedures are in place and are adequate;
(iii) For new facilities, a process hazard analysis has been performed and recommendations have been resolved or implemented before startup; and modified facilities meet the requirements contained in management of change, paragraph (l); and
(iv) Training of each employee involved in operating a process has been completed.
A PSSR is required before introducing HHCs into any new process or a significantly modified process. It's the final safety gate before hazardous chemicals enter the system. Think of it as a structured "ready to start?" checklist.
Four things must be confirmed before startup:
- Construction and equipment match the design specifications (walk-down verification)
- All operating, maintenance, and emergency procedures exist and are adequate
- For new facilities: PHA is complete and all recommendations are resolved or formally accepted. For modifications: the MOC process was followed
- All operators have been trained
The trigger for PSSR on modifications is key: it's required when the modification is significant enough to require a change in PSI. This links PSSR directly to the MOC process — a major change that updates P&IDs, safe operating limits, or equipment specs typically requires a PSSR before startup.
A common gap is performing the PSSR after chemicals are already introduced, or signing off on a PSSR when open PHA recommendations still exist.
Mechanical Integrity
§ 1910.119(j)(j) Mechanical integrity.
(1) Application. Paragraphs (j)(2) through (j)(6) of this section apply to the following process equipment:
(i) Pressure vessels and storage tanks;
(ii) Piping systems (including piping components such as valves);
(iii) Relief and vent systems and devices;
(iv) Emergency shutdown systems;
(v) Controls (including monitoring devices and sensors, alarms, and interlocks); and
(vi) Pumps.
(2) Written procedures. The employer shall establish and implement written procedures to maintain the on-going integrity of process equipment.
(3) Training for process maintenance activities. The employer shall train each employee involved in maintaining the on-going integrity of process equipment in an overview of that process and its hazards and in the procedures applicable to the employee's job tasks to assure that the employee can perform the job tasks in a safe manner.
(4) Inspection and testing.
(i) Inspections and tests shall be performed on process equipment.
(ii) Inspection and testing procedures shall follow recognized and generally accepted good engineering practices.
(iii) The frequency of inspections and tests of process equipment shall be consistent with applicable manufacturers' recommendations and good engineering practices, and more frequently if determined to be necessary by prior operating experience.
(iv) The employer shall document each inspection and test that has been performed on process equipment. The documentation shall identify the date of the inspection or test, the name of the person who performed the inspection or test, the serial number or other identifier of the equipment on which the inspection or test was performed, a description of the inspection or test performed, and the results of the inspection or test.
(5) Equipment deficiencies. The employer shall correct deficiencies in equipment that are outside acceptable limits (defined by the process safety information in paragraph (d) of this section) before further use or in a safe and timely manner when necessary means are taken to assure safe operation.
(6) Quality assurance.
(i) In the construction of new plants and equipment, the employer shall assure that equipment as it is fabricated is suitable for the process application for which they will be used.
(ii) Appropriate checks and inspections shall be performed to assure that equipment is installed properly and consistent with design specifications and the manufacturer's instructions.
(iii) The employer shall assure that maintenance materials, spare parts and equipment are suitable for the process application for which they will be used.
Mechanical Integrity is the most-cited PSM element — approximately 35% of all PSM citations. OSHA's NEP requires inspectors to spend at least 40% of inspection time evaluating MI programs. There are five sub-requirements:
- Written procedures — documented MI procedures for all six equipment categories listed. These must be specific and usable, not generic.
- Maintenance training — maintenance employees (not just operators) must be trained on the process hazards and the procedures applicable to their work.
- Inspection and testing — must follow RAGAGEP (API standards, ASME codes, manufacturer recommendations), be documented with specific required fields (date, inspector, equipment ID, description, results), and occur at appropriate frequencies.
- Equipment deficiencies — if inspection finds a deficiency outside acceptable limits, it must be corrected before returning to service, or a formal safe-operation justification must be documented. Equipment running "temporarily" outside limits without documentation is a citation.
- Quality assurance — parts, materials, and replacement equipment must be verified as suitable for the process application. Installing a carbon steel fitting in a line that requires stainless steel is the kind of QA failure MI is designed to prevent.
The documentation requirement for inspection records is specific: date, inspector name, equipment identifier, description of inspection, and results. Missing any of these fields makes the record non-compliant.
Hot Work Permit
§ 1910.119(k)(k) Hot work permit.
(1) The employer shall issue a hot work permit for hot work operations conducted on or near a covered process.
(2) The permit shall document that the fire prevention and protection requirements in 29 CFR 1910.252(a) have been implemented prior to beginning the hot work operations; it shall indicate the date(s) authorized for hot work; and identify the object on which hot work is to be performed. The permit shall be kept on file until completion of the hot work operations.
Hot work — welding, cutting, brazing, grinding, or any spark- or flame-producing operation — requires a written permit before work begins on or near a covered process. The permit must:
- Confirm that fire prevention and protection requirements (per 1910.252(a)) have been met prior to starting work
- State the authorized date(s) for the hot work
- Identify the specific object or equipment on which hot work will be performed
- Be retained until the hot work is complete
Hot work permits are relatively simple in structure but often cited for procedural failures — undated permits, permits signed after work began, or hot work conducted without any permit. "On or near a covered process" is interpreted broadly — if there's a credible ignition risk from the work, a permit is required.
Management of Change
§ 1910.119(l)(l) Management of change.
(1) The employer shall establish and implement written procedures to manage changes (except for "replacements in kind") to process chemicals, technology, equipment, and procedures; and, changes to facilities that affect a covered process.
(2) The procedures for managing change shall assure that the following considerations are addressed prior to any change:
(i) The technical basis for the proposed change;
(ii) Impact of change on safety and health;
(iii) Modifications to operating procedures;
(iv) Necessary time period for the change; and
(v) Authorization requirements for the proposed change.
(3) Employees involved in operating a process and maintenance and contract employees whose job tasks will be affected by a change in the process shall be informed of, and trained in, the change prior to startup of the process or affected part of the process.
(4) If a change covered by this paragraph results in a change in the process safety information required by paragraph (d) of this section, such information shall be updated accordingly.
(5) If a change covered by this paragraph results in a change in the operating procedures or practices required by paragraph (f) of this section, such procedures or practices shall be updated accordingly.
MOC is the process safety gatekeeper for change. Any change to process chemicals, technology, equipment, or procedures — except a true replacement in kind — must go through a formal review before it happens.
The replacement in kind distinction is critical. If you replace a pump with an identical model at the same specifications, that's RIK — no MOC required. If you replace it with a pump of a different material, different flow rate, or different pressure rating, that's a change — MOC required. This line is where many facilities get cited.
Five things must be considered before any change: the technical basis for the change, safety and health impact, required operating procedure updates, the intended duration of the change, and who is authorized to approve it.
Temporary changes require special attention. Many MOC failures involve temporary changes that were never reversed or formally made permanent. Every temporary MOC should have an expiration date, and the process for extending or closing out temporary changes must be managed.
After the change: Update PSI if needed, update procedures if needed, and train affected employees before startup. All three are required, and all three are commonly missed.
Incident Investigation
§ 1910.119(m)(m) Incident investigation.
(1) The employer shall investigate each incident which resulted in, or could reasonably have resulted in a catastrophic release of highly hazardous chemical in the workplace.
(2) An incident investigation shall be initiated as promptly as possible, but not later than 48 hours following the incident.
(3) An incident investigation team shall be established and consist of at least one person knowledgeable in the process involved, including a contract employee if the incident involved work of the contractor, and other persons with appropriate knowledge and experience to thoroughly investigate and analyze the incident.
(4) A report shall be prepared at the conclusion of the investigation which includes at a minimum:
(i) Date of incident;
(ii) Date investigation began;
(iii) A description of the incident;
(iv) The factors that contributed to the incident; and
(v) Any recommendations resulting from the investigation.
(5) The employer shall establish a system to promptly address and resolve the incident report findings and recommendations. Resolutions and corrective actions shall be documented.
(6) The report shall be reviewed with all affected personnel whose job tasks are relevant to the incident findings including contract employees where applicable.
(7) Incident investigation reports shall be retained for five years.
The incident investigation requirement covers both actual releases and near-misses — any incident that "could reasonably have resulted in" a catastrophic release. Near-miss reporting and investigation is a cornerstone of process safety culture; facilities that only investigate actual incidents are missing the leading-indicator opportunity.
The 48-hour clock starts from the incident, not from when management decides an investigation is needed. Investigation must begin within 48 hours — scene preservation, initial interviews, equipment examination. This is a hard deadline.
Root cause analysis is implied. The regulation requires identifying "factors that contributed to the incident" — not just the immediate cause. A meaningful investigation goes beyond "operator error" to the system, organizational, and design failures that allowed the error to occur.
If contractors were involved, a contractor representative must be on the investigation team.
Recommendations must be tracked and resolved, and findings must be shared with all affected personnel — including contractors where relevant. A completed investigation report that sits in a drawer and is never shared or acted on is still a compliance failure.
Incident reports must be retained for five years.
Emergency Planning and Response
§ 1910.119(n)(n) Emergency planning and response. The employer shall establish and implement an emergency action plan for the entire plant in accordance with the provisions of 29 CFR 1910.38(a). In addition, the emergency action plan shall include procedures for handling small releases. Employers covered under this standard may also be subject to the OSHA regulations, 29 CFR 1910.120 and 40 CFR Part 68.
PSM requires an emergency action plan (EAP) covering the entire facility under 1910.38(a), plus additional procedures specifically for handling small releases. The EAP must address employee roles during emergencies, evacuation routes, alarm systems, and coordination with local emergency responders.
The "small releases" addition is important — your emergency response plan needs to address both major and minor release scenarios. Operators need documented procedures for isolating and mitigating releases before they escalate.
Two additional regulations may apply: OSHA's HAZWOPER standard (1910.120) if you have employees responding to releases, and EPA's Risk Management Program (40 CFR Part 68) which has overlapping but distinct requirements for facilities with covered chemicals. Many PSM-covered facilities are also subject to EPA's RMP.
EAPs must be coordinated with local fire departments, LEPC (Local Emergency Planning Committee), and HAZMAT response teams. Regular drills and exercises are expected.
Compliance Audits
§ 1910.119(o)(o) Compliance audits.
(1) Employers shall certify that they have evaluated compliance with the provisions of this section at least every three (3) years to verify that the procedures and practices developed under the standard are adequate and are being followed.
(2) The compliance audit shall be conducted by at least one person knowledgeable in the process.
(3) A report of the findings of the audit shall be developed.
(4) The employer shall promptly determine and document an appropriate response to each of the audit findings, and document that deficiencies have been corrected.
(5) Employers shall retain the two (2) most recent compliance audit reports.
Every PSM-covered facility must conduct a formal compliance audit of its entire PSM program at least once every three years. The audit verifies that all 14 elements are being implemented as written — not just that documentation exists, but that practices match the documentation.
Key requirements:
- At least one audit team member must be knowledgeable in the specific process being audited
- A written audit report must be produced with specific findings
- Every finding must receive a documented response — what will be done, by whom, by when
- Corrections must be documented as completed
- The two most recent audit reports must be retained (so OSHA can see the trend)
The audit must cover all elements. A compliance audit that only checks some elements is not compliant. OSHA inspectors routinely request audit reports and compare audit findings against what they observe in the field — if the audit missed something an inspector finds, that raises questions about audit quality.
Outside auditors are common and acceptable, but the facility must be meaningfully involved, and findings must be owned and acted on by facility management.
Trade Secrets
§ 1910.119(p)(p) Trade secrets.
(1) Employers shall make all information necessary to comply with the section available to those persons responsible for compiling the process safety information (required by paragraph (d) of this section), those assisting in the development of the process hazard analysis (required by paragraph (e) of this section), those responsible for developing the operating procedures (required by paragraph (f) of this section), and those involved in incident investigations (required by paragraph (m) of this section), emergency planning and response (paragraph (n) of this section) and compliance audits (paragraph (o) of this section) without regard to possible trade secret status of such information.
(2) Nothing in this paragraph shall preclude the employer from requiring those persons to whom access to trade secret information is granted, to enter into confidentiality agreements not to disclose the information.
(3) Subject to the rules and procedures set forth in 29 CFR 1910.1200(i)(1) through 1910.1200(i)(12), employees and their designated representatives shall have access to trade secret information contained within the process hazard analysis and other documents required to be developed by this standard.
Trade secret status does not exempt any information from PSM disclosure requirements. If information is needed to compile PSI, conduct a PHA, write operating procedures, investigate incidents, or perform compliance audits, it must be disclosed — regardless of its trade secret status.
Confidentiality agreements are permitted — you can require people who receive trade secret information to sign NDAs. But you cannot withhold PSM-required information from those who need it on grounds that it's proprietary.
Employees and their representatives also have access rights to trade secret information in PHAs and other PSM documents under the same procedures that govern Hazard Communication (1910.1200) trade secret access — which includes formal requests and confidentiality obligations.
In practice, this element rarely generates citations on its own, but it's invoked when facilities try to limit employee access to PHAs, process information, or incident reports by claiming those documents contain proprietary information.