Overview
ISO 23693-1:2021 - Determination of the resistance to gas explosions of passive fire protection materials - Part 1: General requirements defines a laboratory framework to simulate the mechanical loads that passive fire protection (PFP) materials and systems can experience during gas (and applicable dust) explosions. The standard focuses on reproducing overpressure and drag loading effects, and on specifying instrumentation, test specimens, environmental conditions, data acquisition and reporting requirements to assess PFP resistance to blast loading.
Key topics and technical requirements
- Explosion loading types: Distinguishes finite rise time (near/inside gas cloud) and instantaneous rise time (far-field/shock) overpressure-time histories, characterized by peak overpressure, impulse, and rise time.
- Drag loading: Requires testing of drag forces in addition to pressure where relevant; direct measurement is often impractical so computational fluid dynamics (CFD) or inferred methods may be used.
- Means to generate loading: Acceptable methods include confined/unconfined gas explosions, shock tubes, or solid explosive detonations, each producing characteristic overpressure-time histories.
- Test specimens: Covers typical PFP components such as divisional elements, structural sections, pipework/fittings, penetration seals, windows and doors. Other parts of the ISO 23693 series provide details for specific specimen configurations.
- Instrumentation & measurement:
- Minimum of three pressure transducers, each with a natural frequency ≥ 200 kHz and calibration accuracy ±5%.
- Thermocouples logged for at least 100 s prior to the test at ≥ 1 Hz; accuracy ±3 °C.
- Dynamic and permanent deflection measurement accuracy ±5%.
- Minimum data acquisition sampling frequency 100 kHz; simultaneous sampling; no pre-filtering.
- Photography and high-speed video recommended for visual assessment.
- Data analysis: Signals with duration ≥ 5 ms require a 0.5 ms rolling average for smoothing prior to analysis.
- Test specification & reporting: Test sponsor must define idealized overpressure-time history (peak, impulse, minimum rise time) and additional performance or preconditioning requirements.
Practical applications
- Qualification of PFP coatings, wraps, intumescent materials, and mechanical protection against blast loads from flammable gas releases (including LNG, LPG, hydrocarbons).
- Design verification for assets exposed to explosion risk: chemical plants, offshore platforms, refineries, power stations, tunnels and transportation hubs.
- Risk assessment, product certification, and comparative performance testing in laboratories performing blast testing and structural fire protection evaluation.
Who should use this standard
- Test laboratories and certification bodies
- PFP material and system manufacturers
- Structural and fire protection engineers
- Asset owners, safety managers and regulators
- Research organizations working on blast-resilient fire protection
Related standards
- Other parts of the ISO 23693 series address specific specimen configurations and detailed test methods; consult the ISO catalogue for the complete series.