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Title 8. Industrial Relations
Division 1. Department of Industrial Relations
Chapter 4. Division of Industrial Safety
Subchapter 7. General Industry Safety Orders
Group 16. Control of Hazardous Substances
Article 109. Hazardous Substances and Processes

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§5189. Process Safety Management of Acutely Hazardous Materials.

(a) Scope and Purpose.
These regulations contain requirements for preventing or minimizing the consequences of catastrophic releases of toxic, reactive, flammable or explosive chemicals. The establishment of process safety management regulations are intended to eliminate to a substantial degree, the risks to which employees are exposed in petroleum refineries, chemical plants and other facilities.
(b) Application.
(1) These regulations shall apply to a process which involves a chemical at or above the specified threshold quantities listed in Appendix A or a process which involves a Category 1 flammable gas (as defined in Section 5194) or a flammable liquid with a flashpoint below 100 oF (37.8 oC) on site in one location, in a quantity of 10,000 pounds (4535.9 kg) or more.
EXCEPTIONS: (1) Flammable liquids with a flashpoint below 100 oF (37.8 oC) stored in atmospheric tanks or transferred which are kept below their normal boiling point without benefit of chilling or refrigeration. (2) Hydrocarbon fuels used solely for workplace consumption (e.g. comfort heating propane, gasoline for motor vehicle refueling) if such fuels are not part of a process containing another acutely hazardous chemical covered by section 5189. (3) These regulations do not apply to retail facilities, oil or gas well drilling or servicing operations or normally unoccupied remote facilities.
(2) Explosives manufacturing operations shall comply with the provisions of Article 119 and these orders.
(3) The requirements of subsections (d) and (e) shall become effective within five (5) years according to the following phase-in schedule:
(A) No less than 25 percent shall be completed by August 10, 1994;
(B) No less than 50 percent shall be completed by August 10, 1995;
(C) No less than 75 percent shall be completed by August 10, 1996.
(D) All initial process hazards analyses shall be completed by August 10, 1997.
(4) Subsections (f) through (p) shall become effective on January 4, 1994.
(5) The installation of explosive devices, such as explosive bolts, detonating cords, explosive actuators, squibs, heating pellets and similar small exploding devices into finished products or devices that are not intended to explode and the repackaging of explosives are not considered manufacturing operations and are not covered by Section 5189.
(6) Explosives pre-manufacturing and post-manufacturing research and testing activities listed below are not covered by Section 5189 provided they are conducted in a separate, non-production research or test area or facility, and do not have the potential to cause or contribute to a release or interfere with mitigating the consequences of a catastrophic release from the explosive manufacturing process:
(A) Product testing and analysis which is not a part of any in-production sampling and testing of the explosive manufacturing process;
(B) Chemical and physical property analysis of explosives and propellants and pyrotechnics formulations;
(C) Scale-up research chemical formulations to develop production quantity formulations;
(D) Analysis of age tests conducted on finished products;
(E) Failure analysis tests conducted on pre-manufactured or finished products;
(F) X-raying;
(G) Quality assurance testing (not including the extraction of samples from an active explosive manufacturing production process);
(H) Evaluating environmental effects, such as hot, cold, jolt, jumble, drop, vibration, high altitude, salt and fog; and,
(I) Assembly of engineering research and development models.
(c) Definitions.
Acutely hazardous material. A substance possessing toxic, reactive, flammable or explosive properties and specific by subsection (b)(1).
Explosive. A substance identified in Title 49, Part 172 of the Code of Federal Regulations, the Department of Transportation effective on December 31, 1990.
Facility. The buildings, containers, or equipment which contain a process.
Flammable. Liquids or gases as defined in Section 5194(c) onsite and in one location in quantities of 10,000 pounds or more.
Hot Work. Electric or gas welding, cutting, brazing or any extreme heat, flame, or spark producing procedures or operations.
Major Accident. Any event involving fire, explosion, or release of a substance covered by this section which results in a fatality or a serious injury (as defined by Labor Code Section 6302) to persons in the workplace.
Normally unoccupied remote facility. A facility which is operated, maintained and serviced by employees who visit the unmanned facility only periodically to check its operation and perform necessary operating or maintenance tasks. No employees are permanently stationed to this facility. Facilities meeting this definition are not contiguous with and must be geographically remote from all other buildings, processes or persons.
Process. Any activity conducted by an employer that involves an acutely hazardous material, flammable substance or explosive including any use, storage, manufacturing, handling, or on-site movement of any of the preceding substances 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 an acutely hazardous material could be involved in a potential release shall be considered a single process.
Process Safety Management. The application of management programs, which are not limited to engineering guidelines, when dealing with the risks associated with handling or working near acutely hazardous materials, flammables, or explosives.
Replacement in Kind. A replacement which satisfies the design specification.
(d) Process Safety Information. The employer shall develop and maintain a compilation of written safety information to enable the employer and the employees operating the process to identify and understand the hazards posed by processes involving acutely hazardous, flammable and explosive material before conducting any process hazard analysis required by this regulation. The employer shall provide for employee participation in this process. Copies of this safety information shall be made accessible and communicated to employees involved in the processes, and include:
(1) Information pertaining to hazards of the acutely hazardous and flammable materials used in the process. This information shall consist of at least the following:
(A) Toxicity information;
(B) Permissible exposure limits as listed in Section 5155;
(C) Physical data;
(D) Corrosivity data;
(E) Thermal and chemical stability data;
(F) Reactivity data; and,
(G) Hazardous effects of incompatible mixtures which could foreseeably occur.
NOTE: Safety Data Sheets meeting the requirements of Section 5194(g) may be used to comply with this requirement to the extent they meet the information provisions.
(2) Information pertaining to the technology of the process. Information concerning the technology of the process shall include at least the following:
(A) A block flow diagram or simplified process flow diagram;
(B) Process chemistry;
(C) Maximum intended inventory;
(D) Safe upper and lower limits for process variables such as temperatures, pressures, flows, levels and/or compositions; and,
(E) The consequences of deviations, including those affecting the safety and health of employees.
NOTE: For processes for which data is unavailable, the information concerning the technology of the process may be developed from a process/hazard analysis conducted in accordance with subsection (e).
(3) Information pertaining to the equipment in the process.
(A) Information pertaining to the equipment in the process shall include at least the following:
1. Materials of construction;
2. Piping and instrument diagrams (P&ID's);
3. Electrical classification;
4. Relief system design and design basis;
5. Ventilation system design;
6. Design codes employed including design conditions and operating limits;
7. Material and energy balances for processes built after September 1, 1992;
8. Safety systems (such as interlocks, detection and suppression systems, etc.); and,
9. Electrical supply and distribution systems.
(B) The employer shall document that the equipment complies with the criteria established in subsection (d)(3)(A) in accordance with recognized and generally accepted good engineering practices.
(C) 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.
(4) A copy of the process safety information and communication shall be accessible to all employees who perform any duties in or near the process.
(e) Process Hazard Analysis.
(1) The employer shall perform a hazard analysis appropriate to the complexity of the process for identifying, evaluating, and controlling hazards involved in the process and shall determine and document the priority order for conducting process hazard analyses based on the extent of process hazards, number of potentially affected employees, age of the process and process operating history, using at least one of the following methodologies.
(A) What-If;
(B) Checklist;
(C) What-If/Checklist;
(D) Hazard and Operability Study (HAZOP);
(E) Failure Mode and Effects Analysis (FMEA); or
(F) Fault-Tree Analysis.
NOTE: The employer may utilize other hazard analysis methods recognized by engineering organizations or governmental agencies. In the absence of (A) - (F) or other recognized hazard analysis methods, the employer may utilize a hazard analysis method developed and certified by a registered professional engineer for use by the process hazards analysis team.
(2) The hazard analysis shall address:
(A) The hazards of the process;
(B) Engineering and administrative controls applicable to the hazards and their relationships;
(C) Consequences of failure of these controls;
(D) Facility Siting;
(E) Human Factors;
(F) A qualitative evaluation of a range of the possible safety and health effects of the failure of controls on facility employees; and
(G) The identification of any previous incident which had a likely potential for catastrophic consequences in the workplace.
NOTE: The employer may utilize the facility's Risk Management Prevention Plan(s) (RMPP) prepared pursuant to Article 2, Chapter 6.95 (commencing with Section 25531) of Division 20 of the Health and Safety Code to the extent that is satisfies the requirements of subsections (e)(1) and (2).
(3)(A) 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 operating employee who has experience and knowledge specific to the process being evaluated. The team shall also include one member knowledgeable in the specific process hazard analysis methodology being used. The final report containing the results of the hazard analysis for each process shall be available in the respective work area for review by any person working in that area.
(B) The employer shall consult with the affected employees and where appropriate their recognized representatives on the development and conduct of hazard assessments performed after the effective date of this section. Affected employees and where applicable their representatives shall be provided access to the records required by this section.
(4) The employer shall establish a system to promptly address the team's findings and recommendations; document any actions taken to implement the team's recommendations; develop a written schedule of when these actions are to be completed; assure that the recommendations are resolved in a timely manner; make them available to operating, maintenance and any other persons whose work assignments are in the facility, and who are affected by the recommendations or actions; and assure that the recommendations are evaluated in a timely manner or implement an alternative resolution which appropriately addresses the degree of hazard posed by the scenario.
(5) At least every five (5) years, the process hazard analysis shall be updated and revalidated, by a team meeting the requirements in subsection (e)(3), to assure that the process hazard analysis is consistent with the current process.
(6) Employers shall retain process hazard analyses and/or updates for each process covered by this section, as well as the documented actions described in subsection (e)(4).
(7) Upon request of any worker or any labor union representative of any worker in the area, the employer shall provide or make available a copy of the employer's RMPP.
(8) The employer shall conduct the process hazard analysis as soon as possible but not later than the dates shown in subsection (b)(3).
(f) Operating Procedures.
(1) The employer shall develop and implement written procedures that provide clear instructions for safely conducting activities involved in each process consistent with the process safety information and shall address at least the following.
(A) Steps for each operating phase:
1. Start-up;
2. Normal operation;
3. Temporary operations as the need arises;
4. Emergency operations, including emergency shutdowns, and who may initiate these procedures;
5. Normal shutdown; and,
6. Start-up following a turnaround, or after an emergency shutdown.
(B) Operating limits:
1. Consequences of deviation;
2. Steps required to correct and/or avoid deviation; and
3. Safety systems and their functions.
(C) Safety and health considerations:
1. Properties of, and hazards presented by, the chemicals used in the process;
2. Precautions necessary to prevent exposure, including administrative controls, engineering controls, and personal protective equipment;
3. Control measures to be taken if physical contact or airborne exposure occurs;
4. Safety procedures for opening process equipment (such as pipe line breaking);
5. Verification of raw materials and control of hazardous chemical inventory levels; and,
6. Any special or unique hazards.
(2) A copy of the operating procedures shall be readily accessible to employees who work in or near the process area or to any other person who works in or near the process area.
(3) The operating procedures shall be reviewed as often as necessary to assure that they reflect safe operating practices, including changes that result from changes in process chemicals, technology, and equipment; and changes to facilities.
(4) The employer shall develop and implement safe work practices to provide for the control of hazards during operations such as 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.
(g) Training.
(1) Initial training. Each employee presently involved in operating or maintaining a process, and each employee before working in a newly assigned process, shall be trained in an overview of the process and in the operating procedures as specified in subsection (f). The training shall include emphasis on the specific safety and health hazards, procedures, and safe practices applicable to the employee's job tasks.
(2) Refresher and supplemental training. At least every three years, and more often if necessary, refresher and supplemental training shall be provided to each maintenance or operating employee and other workers necessary to ensure safe operation of the facility. The employer in consultation with employees involved in operation or maintenance of a process shall determine the appropriate frequency of refresher training.
(3) Training certification. The employer shall ensure that each employee involved in the operation or maintenance of a process has received and successfully completed training as specified by this subsection. The employer, after the initial or refresher training shall prepare a certification record which contains the identity of the employee, the date of training, and the signatures of the persons administering the training.
(4) Testing procedures shall be established by each employer to ensure competency in job skill levels and safe and healthy work practices.
(h) Contractors.
(1) The employer shall inform contractors performing work on, or near, a process of the known potential fire, explosion or toxic release hazards related to the contractor's work and the process, and require that contractors have trained their employees to a level adequate to safely perform their job. The employer shall also inform contractors of any applicable safety rules of the facility, and assure that the contractors have so informed their employees.
(2) The employer shall explain to contractors the provisions of the emergency action plan required in subsection (n).
(3) Contractors shall assure that each of their employees have received training to safely perform their job and that the contract employees shall comply with all applicable work practices and safety rules of the facility.
(4) The contractor's training program shall be performed in accordance with the requirements of subsection (g).
(5) The employer when selecting a contractor shall obtain and evaluate information regarding the contract employer's safety program.
(6) The employer shall periodically evaluate the performance of contract employers in fulfilling their obligations as specific in subsection (h)(3) of this section.
(7) The employer shall obtain and make available upon request a copy of the contract employer's injury and illness log related to the contractor's work in the process areas.
(i) Pre-start Up Safety Review.
(1) The employer shall perform a pre-start up safety review for new facilities and for modified facilities for which the modification necessitates a change in the process safety information.
(2) The pre-start up safety review shall confirm that prior to the introduction of acutely hazardous, flammable and explosive materials to a process:
(A) Construction and/or equipment are in accordance with design specifications;
(B) Safety, operating, maintenance, and emergency procedures are in place and are adequate;
(C) For new facilities, a process hazard analysis has been performed and recommendations have been resolved or implemented before start-up; and modified facilities meet the requirements contained in subsection (l); and,
(D) Training of each operating employee and maintenance worker has been completed.
(3) The Pre-Start Up Safety Review shall involve employees with expertise in process operations and engineering. The employees will be selected based upon their experience and understanding of the process systems being evaluated.
(j) Mechanical Integrity.
(1) Written procedures.
(A) The employer shall establish and implement written procedures to maintain the ongoing integrity of process equipment and appurtenances. These procedures shall include a method:
1. for allowing employees to identify and report potentially faulty or unsafe equipment; and
2. to record their observations and suggestions in writing.
(B) The employer shall respond regarding the disposition of the employee's concerns contained in the report(s) in a timely manner.
(C) The employer shall provide employees and their representatives access to the information required in subsection (j)(1).
(2) Inspection and testing.
(A) Inspections and tests shall be performed on process equipment.
(B) Inspection and testing procedures shall follow recognized and generally accepted good engineering practices.
(C) The frequency of inspections and tests shall be consistent with applicable manufacturer's recommendations and good engineering practices and more frequently if determined necessary as dictated by operating history.
(D) The employer shall have a certification record that each inspection and test has been performed in accordance with this subsection. The certification shall identify the date of the inspection; the name of the person who performed the inspection and test; and the serial number or other identifier of the equipment.
(3) Equipment deficiencies. The employer shall correct deficiencies in equipment which are outside acceptable limits defined by the process safety information in subsection (d) before further use, or in a safe and timely manner provided means are taken to assure safe operation.
(4) Quality assurance.
(A) The employer shall assure that in the construction of new plants and equipment modified, repaired, or fabricated equipment is suitable for the process aplication for which they will be used.
(B) Appropriate checks and inspections shall be performed as necessary to assure that equipment is installed properly and is consistent with design specifications and manufacturer's instructions.
(C) The employer shall assure that maintenance materials, spare parts and equipment, meet design specifications and applicable codes.
(k) Hot Work Permit.
(1) The employer shall develop and implement a written procedure for the issuance of “hot work” permits.
(2) The permit shall certify that the applicable portions of the fire prevention and protection requirements contained in Sections 4848 and 6777 have been implemented prior to beginning the hot work operations; indicate the date(s) authorized for hot work; and identify the equipment or facility on which hot work is to be done. The permit shall be kept on file until completion of the hot work operations.
(l) Management Of Change.
(1) The employer shall establish and implement written procedures to manage changes (except for “replacement in kind”) to process chemicals, technology, and equipment, and changes to facilities.
(2) The procedures shall assure that the following are addressed prior to any change:
(A) The technical basis for the proposed change;
(B) Impact of change on safety and health;
(C) Modifications to operating procedures;
(D) Necessary time period for the change; and,
(E) Authorization requirements for the proposed change.
(3) Employees involved in the process shall be informed of, and trained in, the change in the process as early as practicable prior to its start up.
(4) If a change covered by this subsection results in a change to the process safety information, such information shall be appended and/or updated in accordance with subsection (d).
(5) If a change covered by this subsection results in a change to the operating procedures, such procedures shall be appended and/or updated in accordance with subsection (f).
(m) Incident Investigation.
(1) The employer shall establish a written procedure for prompt reporting and investigating every incident which results in or could reasonably have resulted in a major accident.
(2) Incident investigations shall be initiated no later than 48 hours following the incident.
(3) An incident investigation team shall be established and consist of persons knowledgeable in the process involved including a contract employee if the incident involved work of the contractor, and other persons who are qualified to thoroughly investigate and analyze the incident.
(4) A written report shall be prepared at the conclusion of the investigation which includes at a minimum:
(A) Date of incident;
(B) Date investigation began;
(C) A description of the incident;
(D) The factors that contributed to the incident; and,
(E) Any recommendations resulting from the investigation.
(5) The report shall be reviewed with all operating, maintenance, and other personnel whose work assignments are within the facility where the incident occurred.
(6) The employer shall establish a system to promptly address and resolve the report findings and recommendations and shall implement the report recommendations in a timely manner, or take action to prevent a reoccurrence.
(7) Incident investigation reports shall be retained for five (5) years.
(8) The employer shall prepare a report and either provide a copy of the report or communicate the contents of the report to all employees and other personnel whose work assignments are within the facility, where the incident occurred at the time the incident occurred.
(n) Emergency Planning and Response. The employer shall establish and implement an Emergency Action Plan in accordance with the provisions of Section 3220.
NOTE: The employer may use the business plan for emergency response submitted pursuant to subdivision (a) of Section 25503.5 and subdivision (b) of Section 25505 of the Health and Safety Code, to the extent that the requirements of subsection (n) are met.
(o) Injury and Illness Prevention Program. The employer's Injury and Illness Prevention Program required by Section 3203 shall include applicable part(s) of this section.
(1) The scheduled and periodic inspections of facilities covered by this section and required by Section 3203(a)(4) shall be conducted by at least one person knowledgeable in the process.
(p) Employee Participation. The employer shall develop a written plan of action to ensure employee participation in process safety management which includes:
(1) Employer consultation with employees and their representatives on the conduct and development of the elements of process safety management required by this section; and
(2) Providing employees and their representatives with access to all information required to be developed by this section without regard to possible trade secret status of such information.
NOTE: Nothing in this subsection shall preclude the employer from requiring the persons to whom the information is made available under subsection (p)(2) to enter into confidentiality agreements prohibiting them from disclosing the information as set forth in Section 5194.
Note: Authority cited: Section 142.3, Labor Code. Reference: Sections 142.3 and 7856, Labor Code.
1. New section filed 7-10-92; operative 8-10-92 (Register 92, No. 28).
2. Amendment of section and new Appendix filed 1-4-94; operative 1-4-94 pursuant to Government Code section 11346.2(d) (Register 94, No. 1).
3. Change without regulatory effect amending subsection (b)(1) filed 5-3-95 pursuant to section 100, title 1, California Code of Regulations (Register 95, No. 18).
4. Change without regulatory effect amending Appendix A filed 9-13-95 pursuant to section 100, title 1, California Code of Regulations (Register 95, No. 37).
5. New subsection (b)(5) and amendment of Note filed 4-1-96; operative 5-1-96 (Register 96, No. 14).
6. Editorial correction of misspelling of “sulfur” in Appendix (Register 96, No. 18).
7. New subsections (b)(6)-(b)(6)(I) filed 3-31-99; operative 4-30-99 (Register 99, No. 14).
8. Change without regulatory effect amending subsection (n) filed 6-13-2001 pursuant to section 100, title 1, California Code of Regulations (Register 2001, No. 24).
9. Amendment of listing of sulfur dioxide in Appendix A filed 6-18-2002; operative 7-18-2002 (Register 2002, No. 25).
10. Amendment of listing of “Oleum” in Appendix A filed 9-4-2012; operative 10-4-2012 (Register 2012, No. 36).
11. Amendment of subsection (b)(1) and Exception thereto and amendment of subsection (d)(1)(G) and Note thereto filed 5-6-2013; operative 5-6-2013 pursuant to Labor Code section 142.3(a)(4)(C). Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(4) (Register 2013, No. 19).
12. Amendment of subsection (b)(1) and Exception thereto and amendment of subsection (d)(1)(G) and Note thereto refiled 11-6-2013; operative 11-6-2013 pursuant to Labor Code section 142.3(a)(4)(C). Submitted to OAL for printing only pursuant to Labor Code section 142.3(a)(4) (Register 2013, No. 45).
13. Repealer of 11-6-2013 order by operation of law 5-6-2014 pursuant to Labor Code 142.3 (Register 2014, No. 19).
14. Amendment of subsection (b)(1) and Exception thereto and amendment of subsection (d)(1)(G) and Note thereto filed 5-5-2014; operative 5-6-2014 pursuant to Government Code section 11343.4(b)(3) (Register 2014, No. 19).
15. Amendment of Appendix A filed 5-4-2020; operative 5-4-2020. Submitted to OAL for filing and printing only pursuant to Labor Code section 142.3(a)(3) (Register 2020 No. 19).

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