SMOKE VENTILATION SIZER

UNDER TEST - results may not be correct

Industrial Building Smoke Control Screening Tool

For Single-Story Factories, Warehouses, and Large Industrial Enclosures (NFPA 92 / 204 Preliminary Feasibility Assessment)

1. Room & Enclosure Geometry
m
m
°C
m
m
2. Fire Load & Sprinkler Protection
m² fire
💡 NFPA 13 / NFPA 92 Design Fire Area Guidelines

If you are utilizing a Regular Sprinkler System (not ESFR), do not enter the total building area footprint. NFPA recommends evaluating the localized maximum operational target:

Warehouse Hazard Class Sprinkler Type Recommended Design Fire Area
Light / Ordinary Hazard (Class I-IV Storage) Wet-Pipe System 140 m² (≈ 1,500 ft²)
High Hazard (Group A Plastics Storage) Wet-Pipe System 230 m² (≈ 2,500 ft²)
Any Class Layout (High Racks / Deep Storage Footprints) Dry-Pipe System 370 m² (≈ 4,000 ft²)
⚠️ Screening-Level Preliminary Estimate Only. Not a substitute for detailed NFPA 92 analysis, CFD transient safety modeling, or AHJ structural review.
Hazard Mode: -
Effective Fire Input: -
Plume Temp ($T_s$): -
Smoke Filling Time: -
Tenability Level: -
Option A: Mechanical Fan Extraction (NFPA 92 Performance Estimate)
Required Active Plume Extraction Capacity - -
Plume-Driven Engineering Estimates:
  • Fan Thermal Rating Boundary: -
  • Strict Fan Quantity Cap: - units IBC 910.4.3 Cap
  • Required Makeup Intake Air: -
  • Min Free Louver Inlet Area: - (≤ 1.0 m/s velocity rule)
Option B: Natural Buoyant Venting (NFPA 204 Aerodynamic Estimate)
Required Aerodynamic Hatch Clear Area - -
Natural Vent Sizing Estimates:
  • Required Hatch Quantity: - units (Based on standard 3.0 m² aerodynamic opening)
  • Max Spatial Spacing Layout: 30 meters max center-to-center IBC 910.3.3 Limit
  • Fusible Link Sizing Matrix: - NFPA 13 Guardrail
  • Listing Verification Standard: Listed to UL 793 or FM 4430; structured fail-safe deployment.
📋 Core Engineering Model Assumptions
  • Axisymmetric Plume: Assumes classical unconfined thermal plume expansion profiles rising uniformly from a localized source layout.
  • Localized Design Fire: Base energy values calculated symmetrically across a defined sprinkler-controlled area plane.
  • Single Active Reservoir: Thermal boundary calculations assume smoke partitions collect gas volumes in an independent cell ceiling space.
  • Steady-State Behavior: Thermodynamic inputs track uniform mass flow metrics at peak stabilized hazard generation thresholds.
  • Standard Atmosphere: Calculations adopt standard atmospheric barometric profiles ($101.3\text{ kPa}$ baseline sea-level configurations).
Conceptual Smoke Management Evaluation Guidelines (NFPA 13 / 92 / 204 & 2018 IBC Standards):
Ceiling Zoning & Reservoir Parameters:

-

The Sprinkler Interlock Strategy:

-

4. Step-by-Step Calculation Trace & Sizing Estimates
Step 1
Total Mitigated Heat Release Rate (Q / HRR) Assessment Reference: NFPA 92 / Sprinkler Impact Dropdynamics Matrix
Formula: Q = Design Fire Area × Material Intensity (HRR") × Suppression Factor
-
Step 2
Convective Plume Thermal Core Split (Qc) Reference: NFPA 92 Section 5.5 (Standard 70% Convective Energy Partition)
Formula: Qc = Q × 0.70
-
Step 3
Plume Mass Flow Production Footprint (mf) Reference: NFPA 92 Axisymmetric Framework Model (Eq. 5.5.1.1a)
Formula: mf = (0.071 × Qc^(1/3) × Y^(5/3)) + (0.0018 × Qc)
-
Step 4
Smoke Layer Temperature Equilibrium (Ts) Sizing Reference: Conservation of Energy Boundaries driven by Convective HRR
Formula: Ts = Ta + (Qc / (Cp × mf)) [Where Cp = 1.0 kJ/kg-K]
-
Step 5
Volumetric Air Core Dilution & Exhaust Capacity (CFM) Reference: Temperature Density Gas Conversions (ρs = 353 / Ts)
Formula: CFM = (mf / ρs) × 2118.88
-
Step 6
NFPA 204 Natural Aerodynamic Opening Assessment Reference: NFPA 204 Hydrodynamic Buoyant Fluid Loop
Formula: Av = mf / (Cd × √(2 × ρa² × g × d × (Ts - Ta) / Ts))
-