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The purpose of this paper is to establish the influence of oil concentration in oil-in-water emulsions on their flammability on hot surfaces and on their viscosity. The interest in fire test systematization is obviously developing due to many grades and applications of fluids and new design solutions asking for higher parameters in exploitation, including pressure and temperature. Higher temperature and pressure have a synergic effect on fire risk; thus, a special attention has to be given to selecting fluids based on fire tests.

This test simulates a hazardous event when a fluid drops on a hot surface: 10 ml of fluid is dropped during 40-60 seconds on a manifold kept at a constant temperature, from a distance of 300 ± 5 mm above the surface. Tests were done under the procedure of SR EN ISO 20823:2004, with an original equipment. The apparent viscosity of the tested fluids was determined using a rheometer Rheotest 2. The tests were done for the fully mineral oil (Prista MHE-40) and for emulsions with different oil volume in water: 5, 10, 20, 30, 40, 50, 60, 70, 80 and 90 per cent, respectively.

The mineral oil MHE 40 Prista does not burn repeatedly for manifold temperature lower than 440°C, but it burns at 450°C on the clean surface and at 425°C on dirty surface, as obtained after testing the same oil, but at a temperature for which the oil burns. The emulsions do not burn even at 90 per cent oil in water, but the apparent viscosity of the emulsion is too high and unstable, above 20-30 per cent (volume) oil in water. No evident relationship was found between the apparent viscosity of the emulsions and their behavior on hot surface.

The hydraulic fluids were ranked, taking into account the flammability characteristics determined with the help of this test.

This paper aims to reduce the risk of fire in hazardous environments using fire-resistant fluids.

Testing hydraulic fluids under the procedure of SR EN ISO 20823:2004 is required by European and national regulations to avoid large-scale accidents produced by the ignition of hydraulic fluids.

As far as the authors have known, the test procedure was only used for establishing whether a certain fluid passes or does not pass this test. The authors did not find any references for establishing the influence of oil concentration on the flammability characteristics. Also, the equipment has an original design, allowing for a good repeatability and a high protection of the operator.

The purpose of this study is to review and summarise the existing available literature on lightweight cladding systems to provide detailed information on fire behaviour (ignitibility, heat release rate and smoke toxicity) and various test method protocols. Additionally, the paper discusses the challenges and provides updated knowledge and recommendation on selective-fire mechanisms such as rapid-fire spread, air cavity and fire re-entry behaviours due to dripping and melting of lightweight composite claddings.

A comprehensive literature review on fire behaviour, fire hazard and testing methods of lightweight composite claddings has been conducted in this research. In summarising all possible fire hazards, particular attention is given to the potential impact of toxicity of lightweight cladding fires. In addition, various criteria for fire performance evaluation of lightweight composite claddings are also highlighted. These evaluations are generally categorised as small-, intermediate- and large-scale test methods.

The major challenges of lightweight claddings are rapid fire spread, smoke production and toxicity and inconsistency in fire testing.

The review highlights the current challenges in cladding fire, smoke toxicity, testing system and regulation to provide some research recommendations to address the identified challenges.

Despite the April sunshine, the landscape in southern Sweden remained devoid of fresh Spring colours—the result of a prolonged and severe Winter—when Circuit World made the visit to Perstorp earlier this year. The journey to this tranquil inland village crosses fairly flat arable land interrupted here and there by belts of forestation.

In order to meet international standards, PCB base materials have to be flame‐retardant according to the UL 94V specification. Up to now this has been achieved with FR‐4 materials by using brominated aromatic components. Unfortunately, in the case of fire or smouldering, these materials evolve highly corrosive and, under unfavourable conditions, even highly toxic decomposition products. In the search for flame retardancy without the use of bromine, the effect of different structural elements on the burning behaviour of cured resins has been investigated. As a result of these investigations an epoxy resin was developed which contains tailor‐made N‐ and P‐ containing constituents that form flame‐retardant structures during processing and curing of the material. The new material meets all requirements for printed circuit boards and can be processed without any need to modify established technologies. Analytical and ecotoxicological investigations of the combustion products of the new material show that they are comparable with those of wood from the beech tree. The project has already produced first samples of a PCB assembly that successfully passed all functional tests.

Fire retardant materials made of unsaturated polyester resin containing different halides and antimony trioxide were studied. In the present work the addition of a substance rich in halogen such as polyvinylchloride (PVC) and antimony trioxide Sb₂O₃ to the composite made of unsaturated polyester and fiberglass as a reinforced material has been studied. The addition of fire retardant material (PVC) and (Sb₂O₃) enhanced the fire retardancy of the product with remarkable low effect on the mechanical properties of the products. The electrical properties of the products are studied.

The assessment of fuel tank flammability exposure time for transport aircraft is one of the indispensable links in the airworthiness certification process. According to published literature, many factors can affect the flammability exposure time, while systematic analysis and calculations addressing these factors are in shortage.

Based on the requirements for airworthiness certification of domestic large aircraft, the fuel tank flammability exposure time of transport aircraft is calculated with the Monte Carlo evaluation model specified by Federal Aviation Administration. Meanwhile, the influence of each input parameter on the flammability exposure time is obtained by taking user input parameters in the model as independent variables and freezing other factors at the same time. The significance degree of the influence of each factor is discussed by the orthogonal test method. Subsequently, the interaction between the input parameters is studied by response surface method, and a multiple linear regression method is used to establish the functional relationship between the flammability exposure time and the influence parameters.

Research studies show that among the many factors that affect the flammability exposure time, the cruising Mach number, the equilibrium temperature difference and the maximum range are more significant and much attention should be paid to in the airworthiness certification; although there are interactions among various factors, they have different influence on the flammability exposure time, among which the interactions between maximum range and equilibrium temperature difference are the most significant compared with others; established by applying multiple linear regression equation and based on the test data of response surface method, the functional relationship between flammability exposure time and influence parameters is of sufficient reliability and can be used for preliminary prediction of fuel tank flammability exposure time for transport aircraft.

The research achievements of this paper can provide much useful reference for the certification of domestic large aircraft.

In this issue of the Journal we continue with our series on National and International Committees by examining the work carried out by Panel J of the Radio and Electronic Components Manufacturers Federation (RECMF). Note: Readers who are associated with, or are members of committees dealing with printed circuits or applied techniques are invited to contact the Editor with a view to preparing an article on their behalf for publication in this series. This invitation is extended to readers on a world wide basis.

Silicone softeners are widely used in the textile industry to improve the performance of textile products. The thermal characteristics and flammability of polyester fabrics can be influenced by these compounds, which need to be considered, as important issues of human safety. The purpose of this paper is to investigate the changes induced on the polyester fibre by silicone softener treatment using a pad/dry/cure method.

The fibres were first treated with nano‐ and microemulsion silicone softeners. The influence of the silicone emulsion type on thermal properties and flammability of the resultant samples were investigated by various analytical techniques, namely, the differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), dynamical mechanical thermal analysis (DMTA) and horizontal flammability test (HFT).

Results showed that the silicone softeners increase the thermal degradation and flammability of the polyethylene terephthalate (PET) substrate.

The paper's study of thermal and flammability of the silicone‐treated sample is novel and can be used to optimize the properties of silicone polymers during production and consumption.

This study is to investigate the fire safety of textile and clothing materials. It also assesses the flammability for textiles in general.

With the increase in big fires, accidental or non-accidental, people are worrying about the fire behaviour of combustibles. The flammability of textile and clothing materials is a great concern. Appropriate tests should be developed to assess textile and clothing materials to ensure they are safe in a fire. In fact, textile products should satisfy some fire safety criteria depending on their uses. There are specified flammability requirements on selected products, though whether these are good enough for assessing modern textile materials should be watched.

Typical textile materials with and without fire retardants protection were selected for assessing the fire behaviour with a cone calorimeter. High radiative heat flux up to 70 kWm^‒2 was applied to assess those selected textile materials. A cone calorimeter is suggested to be the minimum requirement, though some full-scale burning tests are necessary for some purposes. Heat release rate and flame spreading measures are proposed in ranking the fire safety of textile materials.

Polymer flammability is a subject of growing importance Most of the “things” we use are made of polymers: paper, cotton, wood, fabrics (whether natural or synthetic), and plastics. How these materials will behave when exposed to fire is a question of considerable significance in the current direction of polymer research.