Process Unit Shutdown

{
  "id": "MLC-T-ENV-022304",
  "term": "Process Unit Shutdown",
  "field": "Environment",
  "definition": "1. Work practice or operational procedure that stops production from a process unit or part of a process unit during which it is technically feasible to clear process material from a process unit or part of a process unit consistent with safety constraints and during which repairs can be accomplished. The following are not considered process unit shutdowns: (1) An unscheduled work practice or operational procedure that stops production from a process unit or part of a process unit for less than 24 hours.(2) An unscheduled work practice or operational procedure that would stop production from a process unit or part of a process unit for a shorter period of time than would be required to clear the process unit or part of the process unit of materials and start up the unit, and would result in greater emissions than delay of repair of leaking components until the next scheduled process unit shutdown.(3) The use of spare equipment and technically feasible bypassing of equipment without stopping production. [40 CFR 60.481 (CFR 2013)]\n\n2. Work practice or operational procedure that stops production from a process unit, or part of a process unit during which it is technically feasible to clear process material from a process unit, or part of a process unit, consistent with safety constraints and during which repairs can be affected. The following are not considered process unit shutdowns:(1) An unscheduled work practice or operations procedure that stops production from a process unit, or part of a process unit, for less than 24 hours.(2) An unscheduled work practice or operations procedure that would stop production from a process unit, or part of a process unit, for a shorter period of time than would be required to clear the process unit, or part of the process unit, of materials and start up the unit, and would result in greater emissions than delay of repair of leaking components until the next scheduled process unit shutdown.(3) The use of spare equipment and technically feasible bypassing of equipment without stopping production. [40 CFR 63.1001 (CFR 2013)][40 CFR 63.1020 (CFR 2013)][40 CFR 63.1082 (CFR 2013)][40 CFR 63.1101 (CFR 2013)]\n\n3. Work practice or operational procedure that stops production from a process unit or part of a process unit during which it is technically feasible to clear process material from a process unit or part of a process unit consistent with safety constraints and during which repairs can be effected. An unscheduled work practice or operational procedure that stops production from a process unit or part of a process unit for less than 24 hours is not a process unit shutdown. An unscheduled work practice or operational procedure that would stop production from a process unit or part of a process unit for a shorter period of time than would be required to clear the process unit or part of the process unit of materials and start up the unit, and would result in greater emissions than delay of repair of leaking components until the next scheduled process unit shutdown is not a process unit shutdown. The use of spare equipment and technically feasible bypassing of equipment without stopping production are not process unit shutdowns. [40 CFR 65.2 (CFR 2013)]\n\n4. Cessation of operation of a continuous PAI process unit for any purpose. Shutdown also means the cessation of a batch PAI process unit or any related individual piece of equipment required or used to comply with this part or for emptying and degassing storage vessels for periodic maintenance, replacement of equipment, repair, or any other purpose not excluded from this definition. Shutdown does not apply to cessation of a batch PAI process unit at the end of a campaign or between batches (e.g., for rinsing or washing equipment), for routine maintenance, or for other routine operations.\n\n5. For purposes including, but not limited to, periodic maintenance, replacement of equipment, or repair, the cessation of operation of a chemical manufacturing process unit or a reactor, air oxidation reactor, distillation unit, waste management unit, equipment required or used to comply with this subpart, subpart G or H of this part, or the emptying and degassing of a storage vessel. Shutdown does not include the routine rinsing or washing of equipment in batch operation between batches.",
  "references": [
    "40 CFR 60.481a (CFR 2013)",
    "40 CFR 60.481b (CFR 2024)",
    "40 CFR 63.101 (CFR 2024)",
    "40 CFR 63.1361 (CFR 2013)"
  ],
  "url": "https://mlchart.com/terminology/environment/process-unit-shutdown/"
}