Fire test methods measurement types

Small-scale standard test methods these types of test methods have been developed based on qualitative experiences as well as on the understanding of fire stages and associated hazards. Relatively simple types of measurements are made for various fire properties of the polymeric materials for each fire stage. These types of standard test methods are useful for the performance-based fires codes which are being considered to augment or replace the prescriptive-based fire codes [33-35]. 

Because of this, in most countries the fire regulations specify periods of fire resistance, as measured in a standard fire-test for load-bearing elements, depending upon the size and function of the building. They tend to concentrate on passive rather than active methods of protection, and the required periods of fire resistance are frequently listed in a tabular format relating periods of fire resistance to maximum compartment dimensions and building height for various types of occupancy. 

The main features of real fire performance are the target for simulation or description in classification tests that usually are small or intermediate scale in size. Even smaller scale and very simple methods can be used in product development for cases where classifications tests have been performed that are representative of the product family and type of concern. These tests may be very helpful if the parameter(s) measured are relevant to the larger scale classification test and if a proper correlation can or has been established between the two scales. 

The other group of methods includes those that are based on the registration of the state originated after the shock wave reflection from a barrier. For instance, the detonation pressure m be determined on the basis of the measurement of a thin metal plate firee-surface velocity. The plate free-surface velocity can be determined using optical methods or the electrocontact type of probes and oscilloscope technique. The methods based on the determination of the shock wave velocity through an inert material, e.g., the Aquarium test, are also included in this group. The time resolution of these methods may be on a nanoseconds scale, and even less than a nanosecond, e.g., w en laser interferometry technique is used. Since the processes in the shock fi-ont occur on a nanosecond scale, the present-day techniques are still inadequate to study the detonation wave shock front. 

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