Stairwell Pressurization Testing
When It's Required, How the Test Works, and What Standards Apply
In a high-rise fire, the stairwell is the only way out. Pressurization keeps it free of smoke long enough for everyone above the fire floor to descend. The system either works on the day it's needed — or it doesn't — and there's no in-between. This is the deep dive: every code that triggers it, the NFPA 92 test procedure step-by-step, the pressure differential math, the 30-pound door-opening rule, and the failure modes that show up year after year.
Why this exists at all
In a high-rise fire, the stairwell is the only way out. Elevators are recalled to the lobby (with limited firefighter use), and the floor-by-floor area of refuge approach doesn’t scale beyond a few floors. Everyone above the fire floor descends through stairs, and they pass through the smoke layer to do it.
A 30-story building’s stair has 30 doors connecting it to floors. Every door leak, every door propped open by an evacuating occupant, every smoke-driven pressure imbalance pushes contaminated air into the stairwell. Without active intervention, the stairs fill with smoke from below as occupants try to descend through them.
Stairwell pressurization is the active intervention: a fan (or fans) supplies fresh outdoor air to the stairwell, maintaining a slight positive pressure relative to the floors. When a door opens, air flows OUT into the floor — not the other way. Smoke is held back. Occupants can descend.
The system either works on the day it’s needed or it doesn’t. There’s no graceful degradation. That’s why NFPA 92 prescribes annual testing, why IBC §909 makes the test legally enforceable, and why every state-adopted code treats stair pressurization as a life-safety system on par with sprinklers and fire alarm.
When pressurization is required
Trigger 1 — High-rise
IBC §403.5 + §1023.11. Buildings where any occupied floor is more than 75 ft above the lowest level of fire-department vehicle access are classified "high-rise" under the IBC. Their interior exit stairways must be enclosed as smokeproof enclosures. IBC §1023.11
§1023.12 lists three ways to achieve smokeproof enclosure: (a) natural ventilation through an open-air balcony or vestibule, (b) mechanical pressurization per IBC §909 / NFPA 92, or (c) a pressurized vestibule. New high-rise construction almost always picks (b).
Trigger 2 — NFPA 101 life-safety analog
NFPA 101 §7.2.3. The Life Safety Code parallels the IBC trigger, with the same three methods of achieving smokeproof enclosure. State-adopted NFPA 101 editions (2012 for CMS healthcare, 2018 / 2024 for various states) all keep this requirement. NFPA 101 §7.2.3
Trigger 3 — Atrium + underground
IBC §404.6 atria and §405.5 underground buildings may require smoke-control systems beyond stairwell pressurization. These typically combine pressurized stairs with mechanical smoke exhaust from the atrium / large compartment.
Trigger 4 — Healthcare overlays
NFPA 99 + CMS LSC. Hospitals + healthcare occupancies often carry additional smoke-control system requirements driven by the defend-in-place evacuation strategy. CMS K-Tags reference smoke-control documentation; TJC EC.02.05 expects records of the annual test.
The applicable standards
- NFPA 92 — Standard for Smoke Control Systems. The master standard. Covers design (Ch 4-5), commissioning + acceptance (Ch 8.4-8.5), system integration testing (Ch 8.5), and periodic testing (Ch 8.6). Annual frequency of full-scale testing comes from §8.6.
- IBC §909 — Smoke Control Systems. Code-of-record reference for smoke control. §909.20 covers smokeproof enclosures specifically. §909.18.8 + §909.20.6 mandate that the AHJ require special inspection + periodic test.
- IBC §1023 — Interior Exit Stairways and Ramps. Where the smokeproof enclosure trigger lives, alongside enclosure rating + opening protective requirements.
- IBC §1010.1.3 — Door-Opening Force. The 30-lb cap that constrains how aggressive your pressure differential can be.
- NFPA 101 §7.2.3 — Smokeproof Enclosures. Life Safety Code parallel.
- UL 864 (UUKL category). The fire alarm control unit driving the smoke-control system must be UL 864 listed for smoke control (UUKL is the UL listing category for smoke-control panels). Without UUKL, the FACP cannot be the smoke-control activation device.
- UL 555 / 555S. Fire dampers (UL 555) and smoke dampers (UL 555S) in the relief path or HVAC penetrations.
- ASHRAE Handbook — HVAC Applications, Smoke Management chapter. The engineering reference. Not a code, but referenced throughout NFPA 92 for design principles.
How the system actually works
The basic mechanism: one or more fans pull outdoor air and supply it directly into the stairwell. The supplied air maintains positive pressure inside the stair relative to every floor. Pressure-relief mechanisms (vents, dampers, or barometric controllers) prevent over-pressurization when doors are closed.
Single-injection (SI)
One large fan supplies all the air at the base or top of the stairwell. Simplest, cheapest, but gets pressure-balance challenging in tall stairs (top floors over-pressurized, bottom floors under-pressurized when doors open). Acceptable for shorter buildings (sub-12 stories typical).
Multi-injection (MI)
Air is supplied at multiple points along the stair height, typically every 3-5 floors via dedicated fans or branched distribution. More expensive, much better pressure uniformity. Standard in tall buildings (15+ stories).
Pressure relief
When all doors are closed, the supplied air has nowhere to go. Without a relief mechanism, pressure builds and the door-opening force exceeds 30 lb. NFPA 92 §4.5 requires either a barometric damper, a relief vent at the top, or a variable-flow fan that throttles when pressure rises. The relief mechanism is the most common single-point failure in periodic tests.
HVAC interlock
Building HVAC has to be coordinated. If the building’s return-air system keeps running during a fire, it can pull pressurized stair air out and disrupt the differential. NFPA 92 §4.4.4 + UUKL FACP listings address this — typically the supply-side air handlers shut down on fire alarm and the building goes to negative-pressure exhaust, while only the stair fan keeps running.
Doors open or closed? Which floors? Which force? — the actual test scenarios
The single most common question on stair-pressurization testing: are doors supposed to be open or closed during the test, and on which floors, with what force ceiling? The honest answer requires sorting out a subtle point that gets lost in summary articles — IBC §1010.1.3 has three different door-force thresholds, not one:
The IBC §1010.1.3 force triplet
- 15 lb — to release the latch.
- 30 lb — to set the door in motion (overcome static friction + peak pressure differential).
- 15 lb — to swing the door to the full-open position (after motion has started).
All three apply. A door that takes 30 lb to set in motion AND another 25 lb to fully swing has failed the third test even though it passed the second. The pressurization system has to work within all three constraints, in every scenario.
NFPA 92 §8.6 + IBC §909.20.6 require the system tested under the conditions established by the approved rational analysis, sequence of operations, and commissioning plan. The three scenarios below are the most common combination, but NFPA 92-2021 specifically clarified that door-open testing is required only for doors that are automatically opened during the smoke-control strategy — or when the AHJ, commissioning plan, or original acceptance procedure specifically requires it. Confirm which scenarios apply to your system before assuming any are universal.
Test 1 — System ON, all doors closed
Every stair door closed. Every floor measured. Set-in-motion force ≤ 30 lb at every door. Pressure differential at every closed door within the design range — 0.10–0.35 in. w.g. for the stair-only pressurization alternative under IBC §909.20.4 (sprinklered building); 0.05 in. w.g. stair-to-vestibule + 0.05 in. w.g. vestibule-to-fire-floor for the pressurized stair + vestibule alternative under §909.20.5.2. Confirm which alternative the approved design uses — they are not interchangeable. Verify the door self-closes and latches from full-open after release.
Why this scenario: peak static differential. The system is delivering full pressure with no escape path; if any floor exceeds 30 lb to start motion, the system is over-pressurized and people in a real fire wouldn’t be able to get into the stair. Also catches stuck dampers + jammed pressure-relief vents.
Test 2 — System ON, door-open scenario (when applicable)
Open the door(s) specified by the approved rational analysis, sequence of operations, or commissioning plan — most commonly the fire floor identified in the sequence, or any door automatically opened as part of the smoke-control strategy. At every OTHER closed door, measure: swing-to-full-open force ≤ 15 lb, AND the pressure differential meets the design value documented in the approved package. NFPA 92 §4.4.4 + IBC §1010.1.3
Important — when is this test required? Door-open testing applies when the design strategy specifies it: doors that are automatically opened during smoke-control operation, AHJ-required field simulations, or commissioning conditions in the original acceptance procedure. NFPA 92-2021 dropped the prior assumption that one stair door must be held open during every periodic test. The minimum prescriptive Georgia IBC §909.20.4 stair-only baseline is all interior stair doors closed. Tie any door-open scenario back to the approved design page or the AHJ requirement that establishes it — do not assume it as a universal minimum.
Why 15 lb here, not 30 lb: with a door open, the static differential drops at all other doors (air is escaping through the open door). The set-in-motion force should drop with it. The relevant IBC threshold becomes the swing-to-full-open ceiling: someone partway through evacuation must be able to push their door fully open with ≤ 15 lb. Door must still self-close and latch from full open.
Test 3 — System OFF, all doors
Power off the pressurization. Open every stair door fully. Release. Every door must self-close and latch under its own door-closer alone — without any pressurization assistance, on every floor. NFPA 80 + NFPA 92 §8.5 baseline
Why this scenario: the pressurization system is a backstop to the door closer + latch hardware, not a substitute for them. NFPA 80 + IBC §716 require fire doors to self-close and latch as a fundamental property of the door assembly, regardless of whether smoke control is running. A door that only latches because pressurization is pushing it shut has a hardware deficiency that’s been masked by the active system. When the system fails (fan motor seized, fire alarm panel down, power outage), the door must still close. Test 3 verifies that.
At which floors does the inspector measure?
For Tests 1 + 2: every floor of the stair. Not a sample — every floor. A 30-story building = 30 measurements per test scenario per door (force-to-set-in-motion + swing-to-full-open + differential). The inspector walks the stair top-to-bottom (or bottom-to-top) with a digital manometer + door-force gauge.
For Test 2 specifically: every floor whose door is NOT the open one. If 2 doors are open in a more aggressive variant of Test 2 (some AHJs require simulation of fire floor + level of exit discharge per IBC §909.20.6.3), the other 28 floors get measured.
- Test 1 (system on, all closed): static differential at minimum, 30 lb to set in motion ceiling, self-close + latch verified at every door
- Test 2 (system on, one open): dynamic differential maintained at remaining closed doors, 15 lb swing-to-full-open ceiling, self-close + latch verified at every other door
- Test 3 (system off, all): doors self-close + latch from full open without pressurization help, every door, every floor
- Where some AHJs add a 4th test: system on, multiple doors open (fire floor + level of exit discharge per IBC §909.20.6.3), differential still maintained at all other closed doors
The annual test, step by step (NFPA 92 §8.6)
What the qualified testing agency does on the day:
- Pre-test setup. Building put on test mode with the central station. All exterior doors closed. All interior doors closed except those in the test sequence. HVAC interlocks confirmed in their fire-alarm-active state. Fire alarm zone verified isolated so the test signal is captured + the building doesn’t evacuate.
- Activate the system. Initiate the smoke-control sequence at the FACP / smoke-control panel. Confirm the stairwell pressurization fan starts within manufacturer’s spec time (typically < 60 seconds). Confirm HVAC supply fans shut down.
- Baseline pressure — all doors closed. Use a digital manometer (Magnehelic-style) at every floor of the stairwell. Measure the pressure differential across the closed stairway door. Record at every floor. Target range depends on the design alternative: 0.10–0.35 in. w.g. for stair-only pressurization (IBC §909.20.4 sprinklered building); 0.05 in. w.g. each side of the vestibule for the pressurized stair + vestibule alternative (§909.20.5.2). Maximum is bounded by the 30 lb door-opening force rule, not by a single pressure number.
- Door-opening force — every floor. Use a calibrated door-force gauge attached to the lever / pull side of the door, perpendicular to the door at the lever. Fully release the latch, then pull. Record peak force to start motion + force at full open. Maximum 30 lb at the lever. Failed floors flagged.
- Door-open simulation (when required by approved design). Open the door(s) identified by the rational analysis, sequence of operations, or commissioning plan — typically a door that is automatically opened during smoke-control operation. Measure pressure differential at every other closed door against the design value documented in the approved package. NFPA 92 §4.4.4 — door-open testing scope was revised in 2021
- Multi-door-open scenarios (when in the approved design). Some AHJs and some commissioning plans add fire-floor + level-of-discharge open simultaneously per IBC §909.20.6.3 sequencing. Run only the scenarios in the approved package — do not improvise.
- Pressure-relief verification. Confirm the relief mechanism (barometric damper, top vent, variable-speed fan) operates correctly when all doors are closed. Damper opens, vent passes air, or fan throttles back as designed.
- Smoke-control panel verification. Confirm the UUKL-listed smoke-control panel correctly identifies the active stair, displays system status, and accepts manual override commands per the Sequence of Operations matrix.
- HVAC interlock verification. Confirm building supply fans are off, return / exhaust fans in the correct mode, smoke dampers in HVAC penetrations are in their fire-mode position.
- Restoration. Reset FACP, reset HVAC, take the building off test mode with central station. Document any deficiencies.
- Report. The TAB / FPE issues a signed report covering every measurement, every failure, and a statement of compliance or non-compliance against NFPA 92 + IBC §909. CMS / TJC / fire marshal will all want the report on file.
The IBC §1010.1.3 force triplet — in detail
IBC §1010.1.3 + NFPA 101 §7.2.1.4.5 set three force thresholds on egress doors. All three apply to a stairwell door, and a single door can fail any one of them while passing the others:
- 15 lb to release the latch. Initial force on the lever / panic hardware to disengage the latch. Should be near zero when the door is properly maintained — this threshold catches sticky / corroded / out-of-adjustment latches.
- 30 lb to set the door in motion. Peak force overcoming static friction + the static pressure differential. This is the highest threshold and what most TAB engineers measure first. The 30-lb static-force math: a 36 in × 84 in door at 0.10 in WC differential has ~22 lb of pressure force alone, before adding closer return + hinge friction.
- 15 lb to swing to full open. Once the door is moving, the force to swing it to full open (where the closer arm has the most leverage). This catches over-strong door closers + over-pressurized systems where staff can move the door but can’t actually push it through to fully open.
The pressure-force math at typical differential setpoints (36 in × 84 in door):
- 0.05 in WC differential → static force on the door ≈ 11 lb (well within all three thresholds).
- 0.10 in WC differential → static force ≈ 22 lb (the set-in-motion test gets tight after adding 4-8 lb of closer force).
- 0.15 in WC differential → static force ≈ 33 lb (already over the 30-lb set-in-motion ceiling before adding closer force).
Plus the door closer return force (typically 4-8 lb at the lever — varies with door size + closer adjustment), plus any latch resistance (target near zero), plus door weight on the hinges.
Georgia takeaway — what the code actually requires
The Georgia state minimum is all interior stair doors closed. The Georgia-adopted 2024 IBC §909.20.4 text says verbatim:
“…each interior exit stairway or ramp is pressurized to not less than 0.10 inch of water (25 Pa) and not more than 0.35 inches of water (87 Pa) in the shaft relative to the building measured with all interior exit stairway and ramp doors closed under maximum anticipated conditions of stack effect and wind effect.”
For the alternate path — pressurized stair + vestibule (§909.20.5.2) — the same closed-doors rule applies: 0.05 in. w.g. stair-to-vestibule + 0.05 in. w.g. vestibule-to-fire-floor, all stairway doors closed under maximum anticipated stack pressures, 30 lb maximum door opening force.
Door-open scenarios are NOT part of the Georgia state minimum. One door open at the exit discharge, one door open at the fire floor, every-5th-floor combinations, or dual-door-open simulations are all additional conditions that come from one of:
- The project’s approved rational analysis (the design engineer wrote it in)
- The project’s commissioning / acceptance test procedure
- An NFPA 92 strategy where a door is automatically opened during smoke-control operation (NFPA 92-2021 narrowed door-open testing to this scope)
- An AHJ requirement (Gwinnett Fire Marshal, GA State Fire Marshal, building official)
- A CMS / TJC healthcare survey expectation layered on top of the building code
Tie any door-open test condition back to the approved design page, AHJ letter, or commissioning procedure that requires it. Do not assume it as a baseline minimum. If a TAB firm tests with a door open, the test report should identify which door, which floor, and which source requires the condition.
The Georgia path runs through three layers, all of which can apply at the same time on a high-rise hospital project:
- Georgia Rule 120-3-3 — State Minimum Fire Safety Standards. Substitutes / supplements specific sections of the adopted IBC 909 (smoke-control scope, intake smoke detection, recognized engineering references including NFPA 92 and ASHRAE/SFPE guidance).
- Georgia-adopted 2024 IBC / IFC §909 (DCA + State Fire Marshal) — design, acceptance testing, reporting, smokeproof-enclosure requirements. §909.20 specifically covers the alternatives.
- NFPA 92, NFPA 101, ASHRAE/SFPE Design of Smoke Management Systems, ASHRAE Guideline 5 — recognized engineering references for the rational analysis and commissioning basis. NFPA 92-2021 revised the door-open testing assumption.
For Medicare/Medicaid healthcare facilities, the CMS layer adds 2012 NFPA 101 and 2012 NFPA 99 on top of the building-code path. Both the AHJ acceptance and the CMS/TJC survey expectation matter for the same system.
Acceptance package checklist — what a complete record contains
A TAB report alone is not a complete smoke-control acceptance package. The IBC §909 acceptance package — what should be filed with the AHJ and maintained at the building — includes the items below. Use this as your "do we have it?" checklist.
A. Project + design basis
- Building, address, tower, stair IDs, floors served
- Code of record + adopted standard references
- Design alternative used (stair-only, stair + vestibule, natural ventilation, balcony)
- Approved rational analysis documenting stack effect + wind assumptions + required pressure differentials + door-force criteria
- Fan and relief design values
- Fire alarm / smoke-control sequence of operations
- Firefighter smoke-control panel (FSCS) operation description
B. Test conditions documented
- All stair doors closed (default) — or which specific door is open, on which floor, and the source (rational analysis page / commissioning procedure / AHJ direction)
- HVAC operating condition: minimum speed, occupied normal, fire mode, shutdown
- Fan VFD speed, fan status, damper/relief status
- Fire alarm initiating condition used to start the test
- Standby/emergency power simulation condition
- Weather/ambient condition where relevant
C. Measurements recorded
- Floor-by-floor pressure differential readings
- Door-force readings: latch release, set-in-motion, swing-to-full-open
- Door self-closing and latching verification
- Fan voltage, amperage, rpm, belt status/tension, rotation direction
- Duct traverse + outlet/inlet airflow readings
- Damper function verification
- Intake smoke detector shutdown verification (Georgia Rule 120-3-3 §909.2.2)
- Firefighter smoke-control panel override verification
D. Report closeout
- Design values shown side-by-side with measured values
- Pass/fail criteria + deficiencies + corrective actions + retest results
- Approved agency credentials + calibration certificates
- Responsible registered design professional / FPE / EOR review + sign / seal / date (IBC §909.18.8.3)
- Evidence the report was filed with the fire code official / AHJ (IBC §909.18.8.3.1)
- Charts, drawings, component locations, function descriptions, and maintenance requirements maintained at the building (IBC §909.18.9)
- Written operations and maintenance program
RFI language to use with your contractor / EOR / FPE
If you are responsible for verifying a stair pressurization acceptance package and you have only the TAB report, here is the request to send. Adjust the building / tower references to your project.
"Please provide the complete smoke-control / stairwell pressurization acceptance package for [project / tower], including the approved smoke-control rational analysis, sequence of operations, commissioning / acceptance test procedure, fire alarm and smoke-control panel verification, fan / damper / relief operation verification, standby power simulation, intake smoke detector shutdown verification, and the responsible registered design professional / FPE / EOR review with sign / seal / date.
We have the TAB / retest report, which provides useful pressure and door-force readings. However, the TAB report notes that the agency is not the AHJ and does not determine pass / fail. For our records, please provide the final acceptance documentation showing that the measured values satisfy the approved design intent and Georgia-adopted IBC / IFC §909 requirements, and confirm whether the final report has been filed with the AHJ and maintained at the building.
Please also confirm whether the pressure readings were taken with all interior stair doors closed in accordance with IBC §909.20.4. If a one-door-open or level-of-discharge-door-open scenario is part of the test, please identify the rational analysis page, commissioning procedure, NFPA 92 / ASHRAE basis, or AHJ requirement establishing that condition."
Common failure modes (decoded)
- Damper leakage. Fire dampers (UL 555) and smoke dampers (UL 555S) in the HVAC penetrations into the stairwell don’t fully close, or close but leak past their seats. Each leaking damper bleeds pressure. Most-cited stair-pressurization deficiency in NFPA 92 commentary.
- Fan capacity degraded. Belts slip. Filters dirty. Wheel imbalanced. Bearings worn. The fan still runs, the BMS shows it running, but actual CFM is 60-75% of design. The stair gets "some" pressure but not enough at the worst-case floor.
- HVAC interlock failure. Building return-air system keeps running because the BMS interlock failed or someone overrode it. Pressurized stair air is pulled out through floor returns. Differential collapses.
- Doors propped open. Tenants prop stair doors with wedges, cardboard, fire extinguishers, anything. Each propped door defeats the smokeproof enclosure on that floor. NFPA 80 + NFPA 101 explicitly prohibit propping stair doors.
- Door undercut out of spec. Original install had a 3/4 in floor undercut (per NFPA 80 §6.2). Building has settled, floor finish has changed, gap is now 1.5 in. Pressure leaks under the door. Fix: continuous floor seal or astragal.
- Pressure-relief vent stuck open or closed. Stuck open = no pressure builds. Stuck closed = over-pressurization, doors fail the 30-lb test. The barometric damper on the relief path is the most-overlooked test point.
- Stairway used as utility corridor. Stairs that are also storage or utility rooms accumulate stuff — wet pipes, electrical penetrations, ductwork. Each penetration is a leak unless properly fire- + smoke-sealed. Firestopping integrity is a stair-pressurization issue.
- Fan motor failure. Stair pressurization fans run only during fire alarm + during annual test. They sit idle 99.99% of their life. Bearings seize. Capacitors fail. The system tested fine 12 months ago and is now non-functional. The annual test catches this if it’s actually performed.
- FACP not UUKL-listed. Building was designed when smoke control was an aftermarket addition. The FACP that activates the stair fan isn’t UL 864 UUKL listed. Modern AHJs cite this; old buildings sometimes have a separate smoke-control panel that is UUKL.
Pressurized vestibule — the alternative
IBC §1023.12 also allows a pressurized vestibule in lieu of pressurizing the entire stairwell. A small intermediate room between the floor corridor and the stair is mechanically pressurized; both doors close before either opens (interlocked or via inhabitant compliance). The vestibule acts as a smoke airlock.
Vestibules are common in older retrofits and in jurisdictions where the floor-area cost of vestibules is acceptable. In new construction, full stair pressurization is more common because vestibules cost ~80-120 sqft per floor of usable space.
Healthcare considerations
- Defend-in-place. Hospitals don’t evacuate vertically the way office buildings do. The stair pressurization activation matrix has to handle horizontal evacuation through smoke compartments before vertical evacuation. The smoke-control panel sequence is more complex.
- CMS / TJC documentation. CMS LSC compliance + TJC EC.02.05 expect annual test reports on file. Surveyors will ask. Missing report = K-Tag finding.
- OR / ICU adjacency. Stair pressurization can over-pressurize HVAC zones serving operating rooms or ICUs (which need their own positive- or negative-pressure regimes). Coordination during design + annual test is essential.
- Patient transport in stairs. Evacuation chairs, stair stretchers, pediatric carriers — all require the stair to be wide enough + the door-opening force to be feasible for staff while also carrying a patient. The 30-lb rule is critical here.
Watch: AABC TAB Talk — Mastering Stairwell Pressurization
The AABC’s own deep-dive seminar from a TAB-centered perspective. Worth watching for two reasons. First, AABC (Associated Air Balance Council) is one of the three U.S. certification bodies — alongside NEBB and TABB — that qualifies the field engineers permitted to run this test under NFPA 92 §8.7.2 + IBC §909.18.8. Second, the "TAB-centered approach" means the seminar is from the perspective of the engineer actually walking the stair with a manometer + door-force gauge — not the design engineer or the AHJ. Practical, current, and authoritative.
AABC, ACG, EMA — Leaders in Building Performance. Starts at the relevant test-procedure section. Pairs directly with the NFPA 92 §8.6 + IBC §909 + IBC §1010.1.3 references above.
Owner + facility-manager checklist
- Annual NFPA 92 test on file with a qualified TAB / FPE.
- Test report covers EVERY floor, not just spot-checks.
- Door-opening force ≤ 30 lb at every door — not just the average.
- Pressure differential ≥ 0.05 in WC at every floor (or local AHJ minimum).
- UUKL-listed smoke-control panel.
- HVAC interlock verified during test.
- Pressure-relief mechanism verified operational.
- Fan motor tested under load (not just power-on).
- No propped-open stair doors during routine facility walks.
- Door undercuts within spec; floor seals + astragals intact.
- Fire / smoke dampers in HVAC penetrations exercised + verified during the same annual test window.
- Sequence-of-operations matrix on file matches the actual smoke-control panel programming.
Frequently Asked Questions
When is stairwell pressurization actually required?
What pressure differential is required?
What is the 30-pound rule?
How often is the test performed?
Who is qualified to run the test?
What are the most common failure modes?
What's the difference between pressurized stairwell, smokeproof enclosure, and pressurized vestibule?
References
1. NFPA 92 (current edition): Standard for Smoke Control Systems. The master standard for design, acceptance, and periodic testing of smoke-control systems including stairwell pressurization.
2. NFPA 101 (current edition): Life Safety Code, §7.2.3 — Smokeproof Enclosures.
3. International Building Code (current edition): §403.5 high-rise stairs, §909 smoke control systems, §1010.1.3 door-opening force, §1023 interior exit stairways + smokeproof enclosures.
4. International Fire Code (current edition): §909 — periodic test enforcement; mirrors IBC §909.
5. UL 864 / UUKL: Standard for Control Units and Accessories for Fire Alarm Systems — UUKL listing category for smoke-control panels.
6. ASHRAE Handbook — HVAC Applications, Smoke Management chapter (informative reference).
7. AABC / NEBB / TABB — TAB firm certification programs that qualify field inspectors for smoke-control testing.
8. NIST GCR 92-616: The Klote-Milke Engineering of Smoke Control Systems — foundational engineering treatise often cited in NFPA 92 commentary.
Open the discussion panel to comment, flag an inaccuracy, add field experience, or ask a question. Approved contributions earn SRP and may be incorporated into the article.