New Technical Guidance Unlocks Accurate ISO 1716 Bomb Calorimeter Testing for All Building Materials

SP NORDTEST 871-90 guide details standardised adiabatic & isoperibol bomb calorimeter workflows for ISO 171 building material calorific testing; Shenyang Baoruitong’s JRZ10 calorimeter fully integrates this authoritative test algorithm for global lab compliance.

August 6, 2026 – The landmark SP NORDTEST Technical Note 757 research document, globally recognised as the definitive operation manual for bomb calorimeter calorific value testing, has become the core technical benchmark adopted by Shenyang Baoruitong Automation Equipment Co., Ltd. (BRT) for its JRZ10 series building material combustion heat tester. The comprehensive NORDTEST guide resolves long-standing ambiguities in ISO 1716 test protocols for wood, PVC, gypsum, composite and halogen-containing construction materials, while BRT’s automated bomb calorimeter embeds all standardised calculation formulas, correction models and sample processing workflows outlined in the paper to deliver audit-ready, cross-border compliant test data for labs worldwide.

About Shenyang Baoruitong Automation Equipment Co., Ltd.

Founded in 2012 and headquartered in Shenyang, China’s industrial manufacturing hub, Shenyang Baoruitong Automation Equipment Co., Ltd. is a professional R&D, production and export manufacturer dedicated to full-spectrum fire safety and construction material performance testing instruments. The company holds ISO 9001 quality system certification and CE product certification, with a 3,000 m² standardized production workshop and a core R&D team of over 20 professional engineers specialising in fire test equipment algorithm development and intelligent control systems.

With more than 14 years of industry experience, BRT’s product portfolio covers a complete lineup of fire performance test gear: bomb calorimeters for combustion heat testing, oxygen index testers, smoke density chambers, vertical/horizontal fire resistance furnaces, cable flame test equipment and plastic pipe hydrostatic pressure test systems. Its instruments are widely supplied to national building research institutes, third-party ISO 17025 certification labs, construction material manufacturers and university fire engineering labs across over 30 countries including the EU, USA, Australia and Southeast Asia.

BRT’s independent software development team fully translates the SP NORDTEST 871-90 testing framework into the intelligent control program of its JRZ10 bomb calorimeter, automating Regnault-Pfaundler and Dickinson extrapolation temperature correction, multi-element side reaction correction (chlorine, sulphur, nitrogen oxide) and gross/net calorific value calculation to eliminate manual calculation errors and improve lab testing efficiency significantly. All equipment undergoes three-stage factory quality inspection and 24-hour continuous ageing testing before delivery to guarantee long-term stable measurement precision.

Calorific value is a core fire hazard classification metric for building materials. Materials with high combustion heat release accelerate fire spread, so national and international building codes enforce strict limits on maximum calorific output per square metre of wall and ceiling linings. However, traditional test standards lacked clear guidance for heterogeneous composites, PVC and low-calorific inorganic boards, leading to inconsistent lab results. The NORDTEST guide standardises every testing stage from sample grinding to post-test titration correction, and BRT’s JRZ10 calorimeter is the first domestic fully automatic model that 100% aligns with the guide’s rigorous technical specifications.

Two Core Calorimeter Types Standardised in the NORDTEST Guide & Implemented on BRT JRZ10

Isoperibol (Isothermal Jacket) Bomb Calorimeter

Constant-temperature water bath design requires mathematical offset for heat loss; BRT software auto-executes both Regnault-Pfaundler and Dickinson extrapolation algorithms to compute corrected temperature rise (Θ) without manual spreadsheet work.
Adiabatic Bomb Calorimeter

Zero temperature difference thermal balance design; the JRZ10 system automatically tracks pre-test, main combustion and post-test temperature drift to complete simplified correction calculations as specified in the technical paper.

Standardised End-to-End Test Workflow Built Into BRT JRZ10

All procedural rules defined in the SP guide are embedded into the device’s touchscreen operation system:

1. Intelligent Sample Preparation Guidance

The software outputs tailored preparation schemes based on material types:

Homogeneous wood/plastics: Grind to 250μm powder and support automatic pelletisation
Gypsum, mineral wool and low-combustion materials: Recommend benzoic acid combustion aid with controlled mixing ratio (max 80% total heat contribution)
PVC and halogenated composites: Prompt hydrogen-rich auxiliary fuel addition to convert chlorine into aqueous HCl to match real-world fire chemistry
Auto 20h conditioning parameter reminder (20°C ±2°C, RH 65% ±5%) for hygroscopic specimens

2. Automatic Bomb Assembly & Oxygen Control

The JRZ10 system locks standard oxygen charging parameters (2.452 MPa ±0.1 MPa) and reminds operators to inject 5mL distilled water inside the bomb, consistent with ISO 1716 and the NORDTEST document’s uniform reference state requirements.

3. Auto Side Reaction Correction Calculation (Core Technical Advantage)

The biggest pain point of traditional calorimeters — complex correction for nitric acid, sulphuric acid, chlorine and soot residues — is fully solved by BRT’s pre-programmed formula library:

Nitric acid decomposition correction via titration input
Sulphur element conversion adjustment (SO₂ ↔ H₂SO₄)
PVC chlorine combustion state compensation
Unburned carbon soot heat loss offset (33 J/mg carbon)

The instrument instantly outputs gross calorific value (qᵥ,gr) and net calorific value via the standard formula: qᵥ,net = qᵥ,gr − 206 × [H] after users input sample hydrogen content.

4. Standardised Benzoic Acid Calibration Module

Fully follows the guide’s calibration requirements: minimum 5 groups of benzoic acid pellet combustion tests, auto calculates the calorimeter constant ε and flags results if standard deviation exceeds 0.2% to ensure instrument accuracy before formal testing.

Wide Applicable Material Range Supported by BRT JRZ10

Fully compatible with all construction substrates covered in the NORDTEST guidance:

Timber, plywood, OSB, PVC/ABS plastic panels, gypsum wallboard, mineral wool insulation, composite façade claddings, flooring materials, flame-retardant modified building compounds.

Key Benefits of BRT’s NORDTEST-Aligned Calorimeter

Zero manual calculation: All complex thermodynamic formulas preloaded, eliminating human error in correction computation
Global standard compatibility: Test reports satisfy ISO 1716, GB/T 14402 and Nordic building code audit requirements
Difficult sample adaptive logic: Optimised combustion aid matching for non-self-burning inorganic materials
Long-term data storage: Automatically archives full test curves, titration records and calibration files for third-party audit traceability
Customised service: BRT provides free technical training covering the full SP NORDTEST testing workflow for all equipment purchasers

Target End Users for BRT JRZ10 Bomb Calorimeter

ISO 1716 accredited third-party fire safety testing laboratories
Wood, plastic, insulation and façade material manufacturers’ R&D & QC labs
University fire engineering and material science research institutes
National construction product certification authorities
Flame retardant chemical development enterprises