ISO 1716:2018

Overview

ISO 1716:2018 - Reaction to fire tests for products - Determination of the gross heat of combustion (calorific value) - defines a standardized laboratory method to determine the gross heat of combustion (QPCS) of products at constant volume using a bomb calorimeter. Intended primarily for solid products, the method yields the calorific value expressed in MJ/kg and includes procedures for calibration, sample preparation and result calculation. The standard also provides guidance for calculating the net heat of combustion (QPCI) (Annex A) and information on test precision (Annex B).

Key topics and technical requirements

• Scope and applicability: Method for solids; liquids may be tested using related procedures (ASTM D240 / IEC 61039 with ISO 1928 equipment) as noted in the standard.
• Principle: Combust specimen in oxygen-filled bomb calorimeter calibrated against certified benzoic acid; calculate QPCS from measured temperature rise, accounting for heat loss and latent heat of vaporization of water.
• Test apparatus: Detailed bomb calorimeter requirements (example parameters given: volume ≈ 300 ± 50 ml; max mass 3.25 kg; casing thickness criteria) and ancillary equipment (stirrer, calorimetric vessel, crucible, ignition leads).
• Calibration and procedure: Water equivalent determination, calibration frequency/conditions, standard test procedure and corrections (including isothermal calorimeter corrections in Annex C).
• Specimen preparation: Sampling, surface density measurement, grinding, conditioning (referencing ISO 554 and EN 13238), and defined specimen types. Methods include crucible method and “cigarette” method for certain product forms.
• Product classification: Definitions and handling for homogeneous vs non-homogeneous products, and treatment of substantial/non-substantial components.
• Results and reporting: Calculation of gross and net heat values, expression of results, test report content and validity rules. Annex D gives an example for non-homogeneous products.
• Safety: Warnings about hazards (toxic gases, explosion risks), requirement for risk assessment, safety instructions and training.

Practical applications and users

• Fire test laboratories performing reaction-to-fire assessments and calorific value determinations.
• Product manufacturers (construction materials, polymers, composites) needing calorific data for safety labels, specifications or regulatory compliance.
• Fire safety engineers and consultants using calorific values in fire modelling and risk assessments.
• Regulatory and certification bodies evaluating products for building codes and fire performance classifications.
• R&D teams developing lower-combustibility materials where calorific value informs material selection.

Related standards and keywords

• Normative references: ISO 554, EN 13238. Cross-references: ASTM D240, IEC 61039, ISO 1928 for liquids.
• SEO keywords: ISO 1716:2018, gross heat of combustion, calorific value, bomb calorimeter, reaction to fire tests, QPCS, QPCI, net heat of combustion, calibration, sample preparation, homogeneous product, non-homogeneous product.