Full scale fire tests

The German Federal Institute for Material Testing (BAM) carried out full-scale fire tests on commercial liquefied-propane storage tanks. Tank volume was 4.85 m in each test (Schoen et al. 1989 Droste and Schoen 1988 Schulz-Forberg et al. 1984). Unprotected and protected tanks filled with propane (50% filled) were exposed to a fire. In some tests, the propane was preheated. 

Droste, B., and W. Schoen. 1988. Full-scale fire tests with unprotected and thermal insulated LPG storage tanks. J. Haz. Mat. 20 41-53. 

Note that this index only produces a relative number. Two products with widely different values of the index might be equally safe if, in fact, neither impedes escape. Conversely, two products with apparently similar values may produce different hazard levels if both products are close to the margin of safety. Thus, the scale for any index must be "calibrated", and it may well be different for each building or type of occupant. Generally, this will require a more complete hazard analysis and/or full-scale fire tests. Protocols for doing this are currently under consideration. 

This presentation covers some of the basic data and derived results are discussed. The gases species of oxygen, carbon monoxide and carbon dioxide and nitrous oxide have been measured for all the tests. In the full scale fire tests hydrogen chloride and hydrogen cyanides were measured. Hydrocarbons and their relative abundance were determined by collecting gas samples on absorbent tubes for later analysis on a gas chromatograph and a mass spectrometer. 

In a joint research project in Sweden under the main title "Fire hazard - Fire growth in compartments in the early stage of development (pre-flashover)" (1, 2) a number of different factors have been studied. In the process of developing a full-scale fire test method - "room-corner" configuration - for surface lining materials, Nordtest NT-FIRE 025, the emission of smoke and gas was studied. That study covers data from thirteen different single and... 

In the full scale fire tests some additional gaseous species were studied specifically, i.e. formaldehyde. Not all gas species were studied in every test. Hydrogen cyanide and hydrogen chloride have only been studied in situations where evolution of these species were suspected. HCN and HC1 have only been studied as collective (2, 5 or 10 minutes) samples for each fire test. It is most preferable to follow the concentrations with direct reading instruments. This has been the case for carbon monoxide, carbon dioxide, oxygen and in three out of four cases for nitrous oxide. Drager tubes were used for measurements of nitrous oxides in the DIN 53436 test. 

For the small scale fire test methods it was possible to determine the mass of the sample burnt. In the full scale fire test this could not be done. To make gas emissions comparable between the fire models, the emissions of gases in the small scale fire tests have been reduced by the amount of material burnt in each case. 

Results full scale fire tests. The analytical results from six of the thirteen materials investigated in the full scale fire test art presented in Table II. The integrated amount of each gas from the start of the experiment until flash over in the room has occured i ... 

A qualitative comparison of the results from the gas chromatography - mass spectrometer study of the different hydrocarbons from the wood materials, did not show significant differences between results from one method to the other. As far as can be judged it is mainly the amount of each component that differs between the small scale test methods and full scale fire tests. 

In the DIN 53436 experiments the oxygen concentration is fairly stable over each experiment and varies between 13 to 18 % for the different materials. For the full scale fire test the oxygen concentrations stays close to the ambient almost all the way up to point of flashover. 

Sundstrom, B. Full Scale Fire Testing of Surface Materials Technical Report SP-RAPP 1986 45, Boras, Sweden, 1986 p 117. 

A large number of procedures are now available for measuring fire properties, but many of them are of little interest since they represent outdated technologies. Thus, in order to obtain a realistic estimate of fire hazard for a scenario it is essential to measure relevant fire properties. Furthermore, the appropriate instruments have to be used, viz. those yielding results known to correlate with full scale fire test results. 

This secondary effect of materials is illustrated by the difficulties encountered, in a recent study [54], when attempts were made to correlate CO concentrations measured in small scale and full scale fire tests. The same small scale equipment (typically the cone calorimeter rate of heat release test) could predict adequately a number of very important full scale fire properties, including ignitability, rate of heat release, amount of heat release and smoke obscuration. It could not, however, be used to... 

Hill, R. G., Eklund, T. I., Sarkos, C. P., Aircraft Interior Panel Test Criteria Derived from Full-Scale Fire Tests. DOT/FAA/CT-85/23, September 1985. 

This work does not give definitive proof, however, that the results from the OSU calorimeter correlate well with those from full scale fire tests. It is likely that this will happen, but the product of two good correlations cannot be guaranteed to give another good correlation. Thus, correlation between OSU calorimeter and full scale fires still remains to be firmly established. 

Using full-scale fire test facilities of the Illinois Institute of Technology-Research Institute (IITRI), Christian and Waterman (69) studied fire and smoke behavior of interior finish materials including fire-retardant-treated wood products. The authors found that the materials performed according to a... 

The NBS (currently the National Institute of Standards and Technology, or NIST) conducted a series of full-scale fire tests in the 1970s to investigate the fire hazard of floor coverings.63 The main concern was flame spread from a fire room to a connected corridor. This work resulted in the development of the radiant flooring panel test. This test is described in ASTM E 648. 

Figure 19.9a-d shows that both the phosphinate FR and the nanoparticles change the structure of char compared with pure PBT. In contrast to the pure polymer, which leaves a char consisting of oligomeric components of PBT, the fire-retarded polymer (by phosphinate or nanoparticles) leaves a char consisting of polycyclic aromatic hydrocarbons (PAHs). The PAH structure of the char is expected to make the char stronger and capable to withstand erosion in full-scale fire tests. This observation is verified from the strength analysis of the char residue in intermediate scale... 

A number of modern full-scale fire test methods have been developed for products, relying on heat release rate measurements, such as those involving testing of upholstered furniture (ASTM E 153792 and CA TB 13391), mattresses (ASTM E 1590,85 CA TB 129,82 CA TB 603,88 16 CFR 1633,19 and ASTM F 1085 [Annexes A1 and A3]171), stacking chairs (ASTM E 1822172), electrical cables (ASTM D 5424,173 ASTM D 5537,174 and UL 1685123), plastic display stands (UL 1975),175 other decorative items (NFPA 289,176 a generic furniture calorimeter test), electrical equipment (UL 2043),120 or wall-lining products (NFPA 265,116 NFPA 286,115 ASTM E 2257,177 and ISO 9705178). In fact, room-corner tests are now being used in the codes, as alternatives to replace the... 

This section provides some additional information about a few of the field scale experiments introduced in Section 8.5.1 under Modeling Methodologies Full Scale Fire Tests. 

As discussed in Section 2.4, there are four basic methods for assessing the fire hazard of commodities for warehouse storage. This includes small-scale fire tests, subjective physical comparison, intermediate or full-scale fire tests, and fire tests based upon calorimetry. The most accurate assessment of the fire hazard of a commodity will be obtained with intermediate or full-scale fire tests and with some commodities, fire tests based upon calorimetry. 

Flammability tests of plastics can be classified in various ways (such as characteristics of the igniting source, size or shape of the test specimen, etc.). In the present discussion, test methods are divided into the following groups testing of materials, testing of products, and full-scale fire tests. 

Full-scale fire tests are not standardized. They are conducted in order to judge the suitability of a product in a certain application or situation. The products or systems to be tested are built into a real arrangement and then ignited to produce a genuine fire. The behaviour of the incorporated materials, products, or constructions can thus be observed under quasi-realistic conditions. 

It has been experimentally demonstrated that the results from the Mini Comer Test are in good agreement with those from full-scale fire tests ... 

The Factory Mutual 25-ft Corner Tesf is used in the United States for examination of the fire spread on wall and ceiling coverings in a 15mxl2m room with height of 7.5 m after exposure to the fire of a 350 kg pile of wood. This kind of test is not very different from the full-scale fire tests to be discussed in Section 3.3. 

Full-scale fire tests are often also necessary with plastics built into cars. ... 

Ships have also been subjected to full-scale fire tests. ... 

Applicability of a material is sometimes decided by full-scale fire tests. For this purpose, test pits have been opened up in several countries with lengths up to some tens of metres. 

Laboratory tests often fail to give a true picture of the behaviour of plastics in a natural fire. This is the reason for conducting full-scale fire tests or so-called model tests for full-scale fires. 

These large-scale experiments are mostly very expensive and can go wrong even when designed most carefully. However, they are sometimes indispensable since the final declaration for applicability of a plastics product may require such tests. Full-scale fire tests are also necessary for correlating laboratory tests with real life situations. 

Most full-scale fire tests have been carried out in the building industry but they are now not infrequent in vehicle production, the furniture industry and other industries. 

Several modelled full-scale fire tests and their conclusions are now discussed, arranged according to the structures tested. 

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