ISO 5660-1:2015

Overview

ISO 5660-1:2015 specifies a standardized laboratory method for measuring the heat release rate (HRR) and dynamic smoke production rate (SPR) of materials and products using the cone calorimeter method. The test exposes specimens in a horizontal orientation to controlled radiant irradiance and an external igniter. Key outputs include HRR (derived from oxygen consumption and exhaust flow), time to ignition (TTI), smoke obscuration (via laser attenuation) and mass loss rate (MLR) recorded throughout the test.

Keywords: ISO 5660-1, cone calorimeter, heat release rate, smoke production rate, reaction-to-fire tests, dynamic smoke measurement, oxygen consumption.

Key topics and technical requirements

• Measurement principles
  • HRR determined by oxygen consumption analysis from combustion product stream (oxygen concentration + flow rate).
  • Dynamic SPR calculated from attenuation of a laser light beam through the exhaust (smoke obscuration recorded continuously).
  • TTI (sustained flaming) and MLR are measured during the test.
• Apparatus and instrumentation
  • Cone-shaped radiant electrical heater, radiation shield and irradiance control.
  • Exhaust duct and flow-measuring instrumentation, oxygen analyser, smoke obscuration measuring system (laser), and weighing device.
  • Specimen holder, retainer frame, ignition circuit/timer, heat flux meters and calibration burner.
• Specimen preparation and test environment
  • Requirements for specimen construction, conditioning and suitability (e.g., composite or dimensionally unstable materials).
  • Horizontal orientation specified; guidance available for other orientations in informative annexes.
• Calibration and quality control
  • Extensive calibration procedures: heat flux, smoke meter (neutral density filters), oxygen analyser, weighing device and flow meters.
  • Data collection, calculation methods and reporting requirements defined for repeatable, comparable results.
• Outputs and calculations
  • HRR (kW/m2 or per specimen), MLR, SPR and smoke obscuration time histories; calibration constants and normalization options included.

Practical applications and users

• Fire test laboratories and certification bodies performing reaction-to-fire tests.
• Product manufacturers (textiles, plastics, foams, composites, furniture, building materials) evaluating flammability, fire performance, and the effectiveness of flame retardants.
• Regulatory agencies, building code authorities and safety engineers using HRR/SPR data for material classification, risk assessment and compliance decisions.
• R&D and materials scientists conducting fire behavior research and comparative material screening.

Related standards

• ISO 5660 series (Part 3: guidance on measurement; Part 4: under preparation for low combustibility).
• Developed by ISO/TC 92 (Fire safety), Subcommittee SC 1.

ISO 5660-1:2015 is a widely adopted, reproducible method for quantifying heat release and smoke production-essential metrics for fire safety assessment, product development and regulatory compliance.