Standard Fire Tests Research Articles

Comparison of an industrial- and a laboratory-scale furnace for analysis of hydrocarbon intumescent coating performance

Due to increasing demands for fire protection in high-risk environments, such as petrochemical processes and offshore platforms, so-called hydrocarbon intumescent coatings are increasingly used to protect structural steel in the event of a hydrocarbon fire. For these coatings, the fire-resistance performance is typically evaluated in a series of costly experiments with industrial-scale (i.e. 1–10 m3) furnaces, programmed to follow a standard hydrocarbon fire test curve. In this work, we propose a laboratory-scale furnace for coating evaluation, which can simulate the conditions of a typical hydrocarbon fire curve, that is, the standard UL 1709. In a case study with five hydrocarbon intumescent coating formulations, the correlation between the laboratory- and the industrial-scale furnace was investigated and a good agreement was found for the temperature progression of the coated steel plates. The physical and chemical properties of the intumescent coating chars were also similar for the two furnaces. In summary, the low-cost, time-efficient laboratory-scale furnace can provide reliable screening of hydrocarbon intumescent coatings and is recommended as a complementary tool for industrial fire tests.

Fire behaviour of CFRP strengthened short SHS steel columns with and without insulation

Carbon Fibre Reinforced Polymers (CFRP) have been used as a potential strengthening material due to the many advantages they possess over conventional strengthening materials in recent times. Their successful applications in strengthening concrete columns have also led to CFRP being used as an external strengthening material in steel columns. However, the lack of knowledge of the fire performance characteristics of CFRP has hindered the CFRP usage in steel columns, which require structural fire ratings. Therefore, this two phase experimental investigation was aimed at investigating the effect of fire on the structural performance of CFRP strengthened short Square Hollow Section (SHS) steel columns. In the first phase, CFRP strengthened short SHS columns were exposed to steady state fire conditions and tested under axial compression until failure. The test results exhibited a severe degradation of the ultimate axial compression capacity beyond the glass transition temperature of the adhesive (66 °C) and showed that the effect of CFRP has diminished completely at 225 °C. In the second phase, CFRP strengthened short SHS columns were insulated with a spray applied insulation material and exposed to standard fire under three load conditions. The standard fire test results showed that the CFRP strengthened and insulated columns were able to achieve more than 60 min of fire rating under 0.2 load ratio suggesting satisfactory fire resistance level. This paper presents the details of the investigation and its results.

Классификация строительных материалов по пожарной опасности

Рассмотрены системы классификации, используемые в отечественной и европейской практике оценки пожарной опасности строительных материалов, при этом применяются как идентичные, так и отличающиеся методы испытаний. Представлен критический анализ подходов к классификации строительных материалов по пожарной опасности и показана возможность использования результатов стандартных испытаний для прогнозирования их поведения при реальном пожаре. Отмечено, что действующая в России система противопожарного нормирования строительных материалов положительно зарекомендовала себя с точки зрения влияния на безопасность людей.The main differences of the fire hazard classification systems for building materials accepted in Russia and the EU countries are considered. It is shown that these classification systems are based on test results following both almost identical and significantly different methods. The analysis of the possibility of predicting the behaviour of building material in a real fire is carried out based on the results of standard fire hazard tests. It is concluded that the data obtained from the results of standard tests cannot be fully used to describe the thermal-oxidative decomposition and burning of building material in a real fire. The analysis of criticism of the domestic classification system described in the scientific literature for classifying building materials as different fire hazard classes is presented. The specified criticism is based on the assertion that the methods used in the framework of the Russian fire hazard classification system for building materials do not regulate the definition of so-called “dynamic” indicators during testing that characterizes a change in a given measured value during testing. It is shown that, firstly, the use of dynamic indicators does not lead to a more complete and adequate assessment of the fire hazard of building materials, and, secondly, the methods used in the framework of the European classification system for building materials by fire hazard have significant uncertainty, including parts of the definition of the above mentioned “dynamic” indicators. Criticism of the Russian fire hazard classification system of building materials is examined regarding the fact that within the framework of one fire hazard class, indicators are collected that by their physical nature are in no way correlated and interrelated. To this, an answer is given that, firstly, the concept of “fire hazard of building material” implies a comprehensive assessment of all indicators that can affect the behaviour of the material in case of fire, with a subsequent contribution to the formation of its dangerous factors and, secondly, such an approach to classification meets international best practices, and in particular European ones. It is noted that the long-standing practice of fire-rated building materials in Russia, based on the current classification, has shown its adequacy and correctness.

Fire resistance of non-load bearing LSF walls with varying cavity depth

Abstract Fire resistance of Light Gauge Steel Frame (LSF) wall systems is important in the emerging mid-rise cold-formed steel construction. Many studies have been conducted in recent times to improve the acoustic, thermal (energy) and fire performance of non-load bearing LSF walls. Increasing the wall cavity depth provides superior acoustic and thermal performance characteristics of LSF walls. LSF walls with increased cavity depth are constructed using different stud arrangements such as single, double and staggered rows of studs. Past research studies have been limited to non-load bearing LSF walls made of single row of steel studs with the same cavity depth of 90 mm. This paper investigates the fire resistance of single, double and staggered stud LSF walls with varying cavity depths under non-load bearing conditions. Four full-scale standard fire tests were conducted to investigate the effects of cavity depth for non-load bearing LSF walls and the results are presented in detail. Fire test results show that the temperatures across the wall depth decrease with increasing cavity depth. LSF walls with two layers of plasterboard lining and wider cavity resulted in increased fire resistance. This study also highlights the detrimental effects of staggered stud LSF wall arrangement causing structural failure of thin-walled steel studs.

Structural fire resistance of partially restrained, partially composite floor beams, II: Modeling

This paper is Part 2 of a two-part investigation of the structural fire resistance of a partially composite, one-way spanning steel floor beam assembly with partial translational and rotational end restraint provided by shear tab connections to a supporting frame. A preceding paper (Part 1) described a pair of experimental tests on structurally identical composite floor specimens (one protected and the other unprotected) that are subjected to fire via a large modular furnace. In this paper, those experimental results are used to validate numerical models that conservatively capture the thermo-mechanical response of the specimen assemblies to fire. Models are developed to maximize simplicity toward implementing performance-based design of these assemblies in practice. Thermal analysis of the steel is performed using a multiple lumped mass approach, which can be implemented via spreadsheet or a simple, non-iterative programmed solution. Thermal analysis of the slab via a simple one-dimensional heat flow model is compared against a more detailed computational solution. Two types of structural finite element analyses were performed: one composed of shell elements (more complex) and another composed of fiber-beam elements (simpler). The results of all models show conservative agreement with the experimental data. These models are used to analyze the tested assemblies for variations in applied load and fire protection thickness to demonstrate the utility of the ASTM E119 standard fire test as a validation baseline for performance-based structural fire engineering evaluation.

Flexural Stiffness of Normal and Sandwich Reinforced Concrete Beam Exposed to Fire Under Fixed Loading

This study focuses on the experimental investigation of normal and sandwich reinforced concrete beam exposed to fire in order to evaluate their flexural stiffness. Two beams specimen of 200×300×4000 mm have been cast and tested under flexural loading. The first one has been a normal concrete beam (N) and the second one has been a sandwich concrete beam (SW) with 50 mm skin thickness and 200 mm core thickness. The skin compressive strength of 25 MPa and the core compressive strength of 15 MPa have been considered. The skin strength has been also applied to the N beam. The beams have been reinforced with a plain bar of 3ϕ12 as a tensile reinforcement and 2ϕ10 as compression reinforcement. Both the tensile and the compression reinforcement have yield strength of 300 MPa. The beams have been tested in a full-size furnace under standard fire testing. Nine thermocouples for measuring temperature have been mounted. An LVDT, which has been protected by fire-resistant material, has been placed at the center of the beam to measure the deflection. The 8.63 kN load has been employed at 1/3 span of the beam. Test results have showed that the flexural stiffness of the beam strongly affected by the accumulative temperature representing temperature and firing time. The strength of the N beam drops significantly after 15 minutes of firing and the beam strength has been totally lost. The firing of 45 minutes has needed to decrease the strength of the SW beam then has decreased gradually until 120 minutes of firing.

Performance of Combustible Facade Systems with Glass, ACP and Firestops in Full-Scale, Real Fire Experiments

Combustible facade systems used in modern buildings envelops have received much attention in recent times due to their involvement in propagation of accidental fires in such buildings. This study presents findings from four full-scale real fire experiments performed on a three-story structure (each room being of plan dimensions $$10'\times 20'$$ and story height $$10'$$) with combustible facade systems involving firestops, aluminum composite panels and glass. Two experiments simulated external fire-spread mechanism through the leap-frog effect (one with external fire source and one with internal fire source). The other two experiments were designed to study internal fire spread mechanism due to failure of firestops, a crucial design component of facade systems which is overlooked by most standardized facade fire tests. The experiments indicated that a facade fire can reach from one story to the next in about 3 min and hence, can severely limit the response and egress time for higher floors of a building. Further, the experiments showed that the facade system was exposed to heat flux levels in excess of $$100\,\mathrm{kW}/\mathrm{m}^{2}$$ with maximum temperatures reaching $$1000^{\circ }\mathrm{C}$$. The existing testing standards consider lower incident flux levels and the gas burners used in most existing test methods can reach maximum temperatures of around $$700^{\circ }\mathrm{C}$$ only. These findings indicate a significant gap between current testing standards and real fire performance of facade systems. A study of failure mechanisms of individual components during the experiments showed the need of considering the system in its entirety rather than performing component level testing. The importance of firestops also became evident through these experiments. Properly designed firestop system ensured good compartmentation and prevented spread of fire to the upper floors, whereas improper firestop allowed fire to spread easily to upper floors. It is expected that the insights presented in this study will be useful to improve facade designs as well as to develop more robust testing procedures.

Improved pyrolysis behavior of ammonium polyphosphate-melamine-expandable (APP-MEL-EG) intumescent fire retardant coating system using ceria and dolomite as additives for I-beam steel application

This study describes the effects of ceria (CeO2) and dolomite [CaMg(CO3)2] additives on the pyrolysis behavior and fire resistive property of conventional intumescent flame retardant (IFR) coating system for I-beam steel substrate called ammonium polyphosphate-melamine-expandable graphite (APP-MEL-EG) system. The fire resistance of various formulations was evaluated using the standard vertical Bunsen burner fire test. Thermogravimetric analysis (TGA) was used to understand the degradation of coating formulations. Observations by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) demonstrated that significant amounts of additives favored the formation of homogeneous compacted char structures, which were predominantly composed of carbon (C), phosphorus (P) and oxygen (O). These three main components of the char were also found to be in various binding combinations with other lighter elements like nitrogen (N) and hydrogen (H) as illustrated by the attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy results. X-ray photoelectron spectroscopy (XPS) further suggest that polyethylene([(CH2–C2H2–CH2)n−]) free radicals were abundant on the char surface for the two best formulations and the binding energy of this radical promoted the formation of aromatic carbon chains that enhanced the char's thermal stability. This means that the selection of appropriate additives and combinations of flame-retardant ingredients could significantly change the morphology of the char layer and improve its thermal stability during fire exposure.

Highly sensitive reflection based colorimetric gas sensor to detect CO in realistic fire scenarios

For early fire detection, the measurement of low and small rising concentrations of the fire typical gas carbon monoxide (CO) is essential. The approach presented herein integrates a highly sensitive colorimetric material into a low cost gas sensor system. The gas sensitive color dye is hosted by silica nanoparticle based supraparticles and then processed to a so-called gas sensor stripe. Changes in the CO concentration enable a change of the sensor stripes color, which is easily detectable as a change of the light that is reflected by the stripe. A diffusion chamber protects the gas sensitive film against harmful environmental influences and interfering light. The capability of the gas sensor system is demonstrated in lab as well as real fire tests. In case of the latter, standardized real fire tests are conducted, as well as realistic mixtures of plastics and wood are smoldered. The developed sensors react in real time to the slowly rising CO concentration during the test fires. Even small amounts of CO (<20 ppm) are reliably detectable.

Comparative energy analysis from fire resistance tests on combustible versus noncombustible slabs

SummaryStandard fire resistance tests have been used in the design of structural building elements for more than a century. Originally developed to provide comparative measures of the level of fire safety of noncombustible products and elements, the recent resurgence in engineered timber construction raises important questions regarding the suitability of standard fire resistance tests for combustible structural elements. Three standard fire resistance floor tests (5.9 m × 3.9 m in plan), one on a concrete slab and two on cross‐laminated timber (CLT) slabs, were undertaken to explore some of the relevant issues. The fuel consumption rate within the furnace was recorded during these tests, and the energy supplied from this was determined. An external fuel supply (from natural gas supplied to the furnace) equating to approximately 3 MW was recorded throughout the concrete test, whereas this was about 1.25 MW throughout the CLT tests. The total heat release rate was calculated using carbon dioxide generation calorimetry; this yielded values of approximately 1.75 MW during the CLT tests (ie, an additional energy contribution of approximately 0.5 MW from the timber). This demonstrates that considerably more energy input (by about 1.25 MW) was needed to heat the system when the test sample was noncombustible. A further series of six large‐scale compartment fire experiments (6 m × 4 m × 2.52 m) was undertaken to further explore comparative performance of combustible versus noncombustible construction when the external fuel load is kept constant and is governed by more realistic compartment fire dynamics. For a fuel‐controlled case, the peak temperatures in the compartment with an unprotected CLT ceiling were approximately 200°C higher than in the compartments with a concrete ceiling, whereas for a ventilation‐controlled case, the compartment with a CLT slab ceiling displayed a burning duration that increased by approximately 15 minutes. Potential implications for standard fire resistance testing of combustible specimens are discussed.

Development and application of a simulation approach for fire and structure interaction of concrete members subject to spalling

SummaryThis paper describes the development and illustrates the use of an approach to model the mechanical performance of a concrete bridge and its structural components exposed to fire and subject to spalling. The work is motivated by some recent fire incidents that involved concrete bridges, the poor state of an increasing number of bridges throughout the United States (which makes them more vulnerable to fire damage), and the lack of design codes and standards that adequately protect bridges against fire. An important objective of the work is to develop a method to predict spalling that captures the principal physical and chemical phenomena but is simple enough so that it can be implemented in a 3‐D structural simulation. The first step in the approach involves using a hydrothermal model to determine if and at what temperature spalling occurs for a specified concrete mix (defined by its composition, type of aggregate, water‐cement ratio, porosity, permeability, etc), free moisture content, and heating rate. The second step uses the resulting “critical spalling temperature” in a coupled thermal and mechanical analysis to determine how spalling affects the performance of the concrete member. The approach is illustrated for two standard fire resistance tests conducted on posttensioned concrete slab systems reported in the literature. The paper concludes with a list of recommendations for additional work to improve the predictive capability of the heat and mass transfer and structural models and to address several challenges with the implementation of the spalling criteria in the structural model.

Design of an ASTM E119 Fire Environment in a Large Compartment

Structural fire protection design in the United States is based on prescriptive fire-resistance ratings of individual load-bearing elements which are derived from standard fire testing, e.g. ASTM E119. In standard fire testing, a custom-built gas furnace is traditionally used to heat a test specimen by following the gas temperature-time curve prescribed in the ASTM E119 standard. The span length of the test specimen seldom exceeds 6 m due to the size limitations of available furnaces. Further, the test specimen does not incorporate realistic structural continuity. This paper presents a basis for designing an ASTM E119 fire environment in a large compartment of about 10 m wide, 7 m deep and 3.8 m high constructed in the National Fire Research Laboratory of the National Institute of Standards and Technology. Using the designed fire parameters, a full-scale experiment was carried out on December 20, 2018. The measured average upper layer gas temperature curve was consistent with the E119 fire curve. The maximum difference between the measured curve and the E119 fire curve towards the end of the test was about 70 °C (7%). The study indicates that by proper design and control, the time-temperature curve for the standard fire testing may be approximated in a real compartment. The experimental method suggested in this paper would allow to extend the application of the standard fire testing to large-scale structures not limited by the size of furnaces, to experimentally evaluate the thermally-induced failure mechanism of structural systems including connections and frames, and to advance fire protection design methods.

Fire technical properties of intumescent and ablative fire resistant glass

Conventional glass materials are weak spots in building fires, and fire codes requires installing fire-resistant glass in specified places. Apart from assessing fire resistance of glass panels by standard tests, there are no universal standards in fire-resistant glass specifications. In standard fire resistance tests, the most relevant performance criteria of fire-resistant glass are integrity, insulation, and radiation. The chemical compositions of the glass products, which depend on the manufacturing method and the required fire resistance standards, are not listed in glass specifications. This article provides an attempt to use calculation method for calculation fire resistance of some types of insulated fire-resistant glass, and describe some specific defects of alkali-silicate gel filled glass. It is shown that recently developed ablative fire resistant glass has some advantage.

Finite Element Modelling of Post-tensioned Timber Beams at Ambient and Fire Conditions

An increased environmental conscientiousness in society and the abundance of timber in Canada has inevitably led to the desire for more timber construction. In order to increase the opportunity for timber products in construction, novel building systems such as post-tensioned (PT) timber have been developed. Limited development on numerical modelling has been done on PT timber systems for the optimization of design for fire performance. In industry, there is need for a modelling software capable of approximating complex timber system behaviours that is accessible to practitioners. This research program serves to evaluate the current capabilities or shortcomings of modelling PT timber in both ambient and fire conditions, and to develop a methodology for analyzing the performance of the system. Several numerical models of PT timber beam tests are developed and validated using general purpose FEM software ABAQUS. This software is a good research tool and the lessons learned may be used to refine an accessible model for practitioners. Various material definitions are compared including isotropic and orthotropic models. The numerical models show highly promising results for demonstrating the loading and failure behaviour of PT timber beams. Material property directionality is paramount, captured best with the use of Hill’s Potential Function for non-elastic behaviour. Ambient beam tests are modelled with accurately demonstrated load–deflection behaviour and peak loads are computed to within 5% of experimentally recorded values. For PT timber beam standard fire furnace tests, beam failure times are modelled within 3 min of experimental beam failure times for various fire exposure durations (about 5%), and load–deflection behaviour and failure mechanisms are accurately demonstrated. Thermal gradients align with the recorded thermocouple readings and char depths are computed within 4 mm of the observed layers.

The discrepancies in energy balance in furnace testing, a bug or a feature?

SummaryThe paper aims to explain the differences found in the heat release rate measurements in a large sample of standard fire tests (EN 1363‐1). A total of 379 tests of vertical assemblies was investigated, all performed in furnace SPARK of the ITB Fire Testing Laboratory, in 2015‐2018. The assemblies were subdivided into two groups—wall assemblies and fire‐rated doors. These assemblies were also compared with the results of the test of a wall built with aerated autoclaved concrete blocks that was considered as the benchmark test. It was observed that walls built with highly insulated sandwich panels require less heat to maintain standard thermal exposure conditions (20%‐30% less) than their counterparts built from gypsum plasterboard or aluminium and fire‐rated glass. In case of doors, it was observed that combustible samples required significantly less heat than the benchmark case (40%‐70% less), which indicates that the combustion of the sample inside of the furnace was an additional, significant source of heat release, that may skew the qualitative assessment of their performance in fire. A more in‐depth discussion of the results is provided, with some ideas on the direction of further developments in fire testing.

Experimental study on insulative properties of intumescent coating exposed to standard and nonstandard furnace curves

SummaryThis paper reports the results of an experimental study on two types of intumescent coating exposed to the ISO834 standard fire and three nonstandard fire curves. The nonstandard fires were all less severe than the standard fire. A total of 72 intumescent coating protected steel specimens were tested. The expanded thickness of intumescent char was measured, and the pore feature was observed. Constant thermal conductivity for each specimen was calculated based on the measured steel plate temperature. Thermogravimetric analysis (TGA) test was carried out, and the results show that more gas is trapped within the coating due to better matching of thermal behaviour between gas evolution and polymer viscosity as the rate of heating increases. The constant effective thermal conductivities for the intumescent coating under the nonstandard fires were 65% (type‐W) and 35% (type‐S) higher than that under the standard fire, which resulted in an overestimation of the coating failure time up to 15 and 11 minutes, respectively. Therefore, it is sometimes insecure to use results from standard fire tests guiding the design of coating thickness for steel elements under nonstandard fire conditions.

Fire resistance of light gauge steel framed wall systems lined with PCM-plasterboards

Phase Change Material incorporated plasterboards (PCM-plasterboards) are used in buildings due to their high thermal storage capacity. However, their fire resistance has not been investigated yet. Hence, this research has investigated their fire resistance through thermal characterisation studies of wallboards and small-scale fire tests of wallboards and Light gauge steel-framed (LSF) walls. This paper presents the results on PCM-plasterboards in comparison with commonly used, fire-rated gypsum plasterboards. The elevated temperature thermal characteristics of PCM-plasterboard and gypsum plasterboard were determined first using thermal property tests whereas small-scale standard fire tests of both types of boards and non-load bearing LSF walls lined with both PCM-plasterboard and gypsum plasterboard were conducted to evaluate the fire resistance. Fire test results showed that the fire resistance levels (FRL) were reduced for PCM-plasterboards compared to gypsum plasterboards while importantly, PCM-plasterboards provided additional fuel to the fire. The LSF walls lined with a combination of PCM-plasterboard and gypsum plasterboard gave a lower FRL with higher stud hot flange temperatures, compared to those lined with gypsum plasterboards only. Fire resistance was greatly affected by the PCM-plasterboard after the fall-off of the first fire side plasterboard layer. Higher stud hot flange temperatures would reduce the FRL of load-bearing walls.

A novel unsupervised corpus-based stemming technique using lexicon and corpus statistics

Word Stemming is a widely used mechanism in the fields of Natural Language Processing, Information Retrieval, and Language Modeling. Language-independent stemmers discover classes of morphologically related words from the ambient corpus without using any language related rules. In this article, we proposed a fully unsupervised language-independent text stemming technique that clusters morphologically related words from the corpus of the language using both lexical and co-occurrence features such as lexical similarity, suffix knowledge, and co-occurrence similarity. The method applies to a wide range of inflectional languages as it identifies morphological variants formed through different linguistic processes such as affixation, compounding, conversion, etc.The proposed approach has been tested in Information Retrieval application for four languages (English, Marathi, Hungarian, and Bengali) using standard TREC, CLEF, and FIRE test collections. A significant improvement over word-based retrieval, five other corpus-based stemmers, and rule-based stemmers has been achieved in all the languages. Besides, information retrieval, the proposed approach has also been tested in text classification and inflection removal tasks. Our algorithm excelled over other baseline methods in all the test scenarios. Thus, we successfully achieved the objective of developing a multipurpose stemming algorithm that cannot only be used for information retrieval task but also for non-traditional tasks such as text classification, sentiment analysis, inflection removal, etc.

Two-way coupled CFD fire and thermomechanical FE analyses of a self-supporting sandwich panel façade system

A self-supporting sandwich panel façade system under fire is studied. First, a thermomechanical FE model, which comprises the complete façade system, and incorporates material degradation and geometrical nonlinear behaviour except for the insulation material and connections, is loaded by a fire temperature curve. Eurocode design rules then predict the screw connections of a sandwich panel will fail in shear. Secondly, an existing programme, FDS-2-Abaqus, is extended to allow its two-way coupled analyses, in which CFD fire simulations are updated for changes in the thermomechanical FE model, to be applicable to the façade system. Again, these simulations show the shear failure of the screws. Parameter studies show differences in system behaviour for improved screw properties; a fuel-controlled vs. ventilation-controlled fire; and different panel thicknesses. Interestingly, as thermal bowing of the panel retards screw failure, and thicker sandwich panels bow less than thinner panels, thicker façade panels will decrease failure time. This and other insights obtained, and the predicted failure of two tiny but critical screws within 80 s, as compared to 150 min lasting sandwich panels in standard fire tests, stresses the need to study complete systems under realistic fires, rather than to study individual components in standard fire tests. Future research will focus on detailed FE models of the connections; full-scale fire experiments; CFD temperature measurement points at the façade outside; detailed modelling of the insulation; and the effects of high temperature creep.

Mechanical integrity of gas turbine enclosure doors under fire test conditions for A0 fire rating

PurposeAs fire doors are passive fire protection parts, the doors have to be certified through standard fire tests. It is usual practice to perform the standard fire testing on the components which require the fire certification. However, some gas turbine enclosure doors are too large to test at the test facility and hence the fire resistance test is practically not possible. The purpose of this paper is to develop a reliable finite element model, validate the model using the specimen door test results and extend the method to actual gas turbine enclosure doors to support the fire certification.Design/methodology/approachFirst, the standard fire testing on enclosure door test specimen was carried out. Second, the finite element analysis model was built and tuned to match the standard fire test deflections, and finally, the same modelling technique was extended to model the actual gas turbine enclosure door to verify the results for fire certification process.FindingsGap analysis, a method of post processing is suggested for result analysis. It was found suitable to verify the gap openings which are required for A0 rated fire certification according to fire test procedure code and also to check the mechanical integrity of the enclosure door frame assembly.Originality/valueThe method presented in this work could be used as support information along with the test specimen results for A0 class fire rating certification of the doors according to International Maritime Organization Resolution MSC.307 (88) Annexure 1: Part 3.