2.3 IIAR 7 Operating Procedures and IIAR 9 Existing Systems

IIAR 7: Procedures You Can Hand a Night Operator at 02:00

Quick Answer: ANSI/IIAR 7 is how an ammonia plant develops and maintains written operating procedures. ANSI/IIAR 7-2025, Standard for Operating Procedures for Closed-Circuit Ammonia Refrigeration Systems, was ANSI-approved on 7 July 2025 (earlier editions were titled Developing Operating Procedures). IIAR 7 is ammonia-specific procedure content; OSHA 1910.119(f) is the PSM legal duty those procedures must satisfy at covered plants.

A beautifully designed IIAR 2 engine room still injures people if the only “procedure” is tribal knowledge. OSHA’s operating-procedure element exists because shutdowns, oil drains, and emergency isolations go wrong when the steps live in one lead operator’s head. IIAR 7 is the ammonia RAGAGEP for building those procedures so they match the equipment that is actually installed.

What IIAR 7 is for

IIAR 7 defines minimum requirements for developing operating procedures for closed-circuit ammonia refrigeration systems. It is aimed at the people who write, define, and review those procedures—not only at the person who turns the handwheel. Certificate-course outlines for IIAR 7 walk through procedure content for compressors, refrigerant pumps, condensers, evaporators, pressure vessels, purgers, oil-removal devices, and safety systems, plus how procedures are maintained. The 2025 revision added example procedure templates and P&IDs in an appendix. Those templates are informative; they do not excuse a plant from writing procedures that match its vessels, valve numbers, and interlocks.

IIAR 7 is not a substitute for IIAR 2 design, IIAR 6 ITM, or a PHA. A procedure that says “start the screw” without the actual oil-pressure, slide-valve, and detection interlocks is a fiction. Procedure writers pull from process safety information (P&IDs, setpoints, relief design, detection setpoints) and from IIAR 2/6 safeguards.

Alignment with OSHA 1910.119(f)

OSHA 1910.119(f)(1) requires the employer to 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. The procedures must address at least:

• Steps for each operating phase, including initial startup, normal operations, temporary operations, emergency shutdown (including the conditions that require it and who is responsible), emergency operations, normal shutdown, and startup after a turnaround or emergency shutdown.
• Operating limits, consequences of deviation, and steps to correct or avoid deviation.
• Safety and health considerations (hazards, precautions, PPE, first aid, unique hazards).
• Safety systems and their functions (detection, ventilation, e-stops, relief, interlocks).

OSHA also requires procedures to be readily accessible to employees who work the process, to be reviewed as necessary to reflect changes, and to be certified annually as current and accurate. Safe work practices for lockout, confined space, and similar control of hazards sit beside the operating procedures.

IIAR 7 is how ammonia plants meet that list with refrigeration-specific content. A CIRO exam stem that says “the SOP binder is locked in the plant manager’s office and the night crew has never seen the emergency shutdown procedure” is an accessibility failure under both OSHA 1910.119(f) and IIAR 7. A stem that uses the normal oil-drain SOP during a 200 ppm release is a normal versus emergency failure.

Emergency procedures are not the Monday startup checklist

Normal operations assume detection is quiet, ventilation is in AUTO, and the e-stop has not been hit. Emergency operations assume a leak, a fire, a power loss, or a ventilation failure. IIAR 7 expects those to be separate, usable instructions:

• Who hits the refrigeration e-stop versus who verifies emergency ventilation is ON.
• When 25 ppm monitored-location response (investigate, restrict access) becomes a 150 ppm do not enter / ventilation latched event.
• How to communicate with the monitored location and the emergency plan (which will also intersect EPA RMP and the plant EAP in later chapters).
• What not to do—for example, entering to “reset the fan locally” when the latch exists specifically so ventilation continues.

If procedures were last updated when the plant had reciprocating machines and the room now has screws, VFDs, and a new high-level cutoff, IIAR 7 and 1910.119(f) both say the procedures are stale. IIAR 9 will later ask whether the plant even reviewed those procedures as part of the existing-system evaluation.

Supervisor scenario: writing the e-stop procedure

You are asked to “write a quick SOP” because corporate wants something before an audit. The wrong product is a one-page “hit the red button.” The IIAR 7 / 1910.119(f) product names the principal-door e-stop, states that it stops refrigerant compressors, refrigerant pumps, and specified automatic valves, states that emergency ventilation remains available (ON/AUTO still works; emergency fans are not on that off-only circuit), tells operators when emergency shutdown is required, assigns responsibility, and tells them how to reset only after the condition is understood. That is supervisor-level procedure writing.

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IIAR 9: Minimum Safety for Systems That Already Exist

ANSI/IIAR 9-2020, Standard for Minimum System Safety Requirements for Existing Closed-Circuit Ammonia Refrigeration Systems, with Addendum A (2024), is the existing-system standard. IIAR published Addendum A to clarify scope, the compliance date, and selected technical requirements, and to add an informative flowchart for conflicts with original codes.

What IIAR 9 is — and what it is not

IIAR 9 is not a design standard for new equipment. New vessels, new machinery rooms, and new installations are IIAR 2 (design), IIAR 4 (installation), and IIAR 5 (startup). A plant that “IIAR 9’s” a brand-new penthouse package to avoid IIAR 2 detection is answering the wrong book.

Addendum A tightened scope: existing stationary closed-circuit vapor-compression systems using ammonia in industrial occupancies shall comply. It is not a license to ignore original codes. Where the codes and standards that originally governed design and installation are more restrictive than IIAR 9, those more restrictive provisions generally continue to apply, unless IIAR 9 specifically allows a listed reduction. Where IIAR 9 is more restrictive than a weak original installation, IIAR 9 is the floor.

Expect IIAR 9 minimums to be lower than IIAR 2-2021 new-design in places. IIAR 9’s own checklist, for example, still frames existing machinery-room detection as at least one detector and emergency-ventilation activation at no higher than 1,000 ppm, while reminding readers that NEC unclassified-room practice still wants 150 ppm ventilation where NFPA 70 is enforced. Do not memorize IIAR 9 as if it were IIAR 2-2021. The exam wants you to know that existing plants have a minimum-safety evaluation, and that closing an IIAR 9 gap is not the same as rebuilding the room to IIAR 2-2021 unless the work is actually new design.

The dates you must not miss

Addendum A added a clear clock:

• §1.3.1 — Initial evaluation: An initial safety evaluation shall be conducted for each ammonia refrigeration system to ensure it complies with IIAR 9 no later than 1 January 2026.
• §1.3.2 — Revalidation: Safety evaluations shall be revalidated at least every five (5) years.

If today is 9 September 2026, the initial MSSE should already exist. The next fight is the five-year revalidation and any open gap-closure work. “We were going to start the evaluation next shutdown” is not a 2026 answer.

What the minimum system safety evaluation covers

IIAR’s Minimum System Safety Evaluation (MSSE) checklist states the scope in four blocks:

1. Documentation — review and verification of equipment and system-component documentation.
2. ITM program review — is there an inspection, testing, and maintenance program (the IIAR 6 question), not merely a binder spine.
3. Operating procedures review — are there procedures (the IIAR 7 / 1910.119(f) question).
4. Physical inspection of the ammonia system against applicable minimum safety requirements (location of equipment, machinery-room features, detection, ventilation, emergency switches, and related items).

Results and the method used to find gaps are documented on the checklist or an equivalent form. An evaluation that never leaves the conference room is not a physical inspection. An inspection that never opens the SOP cabinet is not a procedure review.

Closing gaps like a supervisor

Gap closure is work planning, not a slogan. Missing entrance strobes on an existing room may be an IIAR 9 detection/alarm gap. Adding a new compressor still drags IIAR 2 into the job. If original code required something more restrictive than IIAR 9, you do not get to relax it because Addendum A exists. If the MSSE finds no written emergency-shutdown procedure, you do not “inspect harder”—you write IIAR 7 procedures and train to them.

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The IIAR Suite Map (Depth Is 2 / 6 / 7 / 9)

IIAR is the ANSI-accredited ammonia (and now broader natural-refrigerant) standards body. Candidates must pick the right standard even when this chapter’s depth is 2, 6, 7, and 9.

Four exam stems, four standards

1. “We are adding a high-pressure receiver and dual relief in the engine room.” → IIAR 2 design (then 4 and 5). Not IIAR 9.
2. “When were the detectors last calibrated, and does the 150 ppm fan still latch?” → IIAR 6 ITM (the design setpoints still come from IIAR 2).
3. “Write the procedure for emergency shutdown and for oil draining.” → IIAR 7, mapped to 1910.119(f) phases, kept accessible.
4. “Corporate wants the existing 1999 plant checked against minimum ammonia safety, with a report by the IIAR 9 deadline, then every five years.” → IIAR 9 MSSE. Closing those gaps does not secretly convert the job into a new IIAR 2 design package unless you are actually installing new equipment.

That selection skill is the CIRO supervisor skill this chapter exists to build.