1 (SA, 1984) and the ‘early fire hazard’ test. 3 C. Liquids with lower flash points ignite easier. WARNING: If the sample material is explosive or extremely flammable, do not conduct this test. Flammability components included: combustibility (a, b); ignition temperature (c, d); time to ignition (e, f), and, fire sustainability (g, h). QAI performs fire and flammability testing for materials and large scale building products, surface burning characteristics (Steiner tunnel), small-scale flammability, and flammability testing of furniture for both residential and commercial markets. R. Yes, flammability is a chemical property. The test evaluates both the burning and afterglow times and dripping of the burning test specimen. 461. All three of these parameters are generated from the explosion severity test. Trex "Escapes" decking is rated Class A, and "Accents" and "Transcend" are rated Class B. We are equipped to test a wide range of fabrics and textiles, consumer and industrial garments and other apparel, as well as furniture products. the flammability limits of the fuel [7] with $ ranging from approximately 0. The ignitibility of live foliage was lower and the combustibility was higher in Cupressaceae. The DOT defines Hazard Class 3, flammable liquid as a liquid with a flash point at or below 60°C (140°F). ) and Aleppo pine (Pinus halepensis L. However, the difference in flammability between different vodka brands is generally negligible. The words come from Latin. If a material has a flashpoint higher than the usual temperatures in the climate zone or work environment where the material will be used or stored, it is combustible rather than flammable. : ignitability, sustainability, combustibility and consumability. If the draft label has no claim of non-flammability, skip this section. A clear distinction emerges between the properties ‘flammability’ and ‘ignitability’ by defining them in terms of temperature. The safety can used for flammable liquids is an excellent example of fuel management. 8378. People sometimes get confused and think that. V-2. There are numerous resources containing large amounts of gas flammability data (e. Effcct of initial temperature on limits of flammability of a combustible vapor-inert-air system at atmos-The program is described in UL 94, the Standard for Tests for Flammability of Plastic Materials for Parts in Devices and Appliances , which is now harmonized with IEC 60707, 60695-11-10 and 60695-11-20 and ISO 9772 and 9773. 2 Estimation of the dilution level to reduce the flammability of a liquid mixture Predictive mixing rule can also help to define the level of dilution needed to lower the flammability of aExample Sentences: (1) "Monasteries and convents face greater risks than other buildings in terms of fire safety," the article said, adding that many are built with flammable materials and located far away from professional fire brigades. Sometimes,. <iframe src="height="0" width="0" style="display:none;visibility. DOT’s 49 CFR Rules for Class 3 and 4 Materials. The Flammable Range (also called Explosive Range) is the concentration range of a gas or vapor that will burn (or explode) if an ignition source is introduced. Experimental results are presented for the flash point, fire point and sustained combustibility. 1% to 6. So, let’s take a look at the differences between physical and. 1 – Combustibility Tests for Materials; and. Flammability classification of materials due to flame spread rate Flooring material Flame spread rate [mm. The often inevitable hazards of fire make wood a very desirable material for further investigation. All oil-based paints are flammable. The BCA requires flexible membranes, referenced as sarking type material, to have a flammability index less than 5 and thickness less than. Type I problems cover flexible oxygen levels in a closed domain, while type II problems deal with fuel streams in a fixed background. It shows that (x_{LU}) is almost unchanged by the dilution ratio, so MOC is almost constant, independent of the dilution of fuel. They can be solid as well as liquid. Flammability diagram for the system mcthane-oxygen-nitrogen at atmospheric pressure and 26" C- - - - 1 I. Answer #1: The terms "combustible liquids" and "flammable liquids" are defined in the construction standard at 29 CFR 1926 and in the general industry standard at 29 CFR 1910 as follows: The definitions in the two standards are different because the definitions were adopted from different sources. Non-combustibility test (EN ISO 1182): This test determines the non-combustibility of homogeneous building materials. next lesson > Powered by Create your own unique. Combustible. 1 standard combustibility test. This is an important property to consider when a substance is used for construction or is being stored. To definitively prove that aluminum does not burn, the Aluminum Association commissioned the testing of various aluminum alloys in 2011 and 2020 according to ASTM E 136 “Standard Test method for Assessing Combustibility of Materials Using a Vertical Tube Furnace at 750°C. ) and Aleppo pine (Pinus. 5. The Science Behind Vodka's Combustibility. In English, we think of in- as a prefix that means "not": inactive means "not active," inconclusive means "not. acetone . ilex. 42 flammable gas is classified in in Category 1A, 1B or 2 according to the following Table 1. In this case, A2L has lower flammability and toxicity compared to other classifications—making it the second safest refrigerant category. 3 kPa: (a) are ignitable when in a mixture of 13% or less by volume in air; or (b) have a flammable range with air of at least 12 percentage points regardless of the lower flammability limit. The effects of plant traits on the flammability of 276 species were investigated ( Table 1 ). In order for a hydrogen fire to occur, an adequate concentration of hydrogen, the presence of anBy Perrine Juillion / July 23, 2019. 94 ºF. Chemical. Most hardware stores sell a cheap red metal can with a screw-on lid for gasoline. )”. Paper-faced gypsum wallboard does not pass the non-combustible faming criteria (Canadian Wood (Canadian Wood Council 1991)). Class F – Easily flammable. 4. Flammable liquids have a flash point of less than 100°F. HORROCKS, in Fabric Testing, 2008 Upholstered seating furniture. p. theory that everything is made of tiny particles in constant motion. On the other hand, combustible substances need a higher temperature to catch fire. This test measures the self-extinguishing time of the vertically oriented polymer specimen. The answer is yes; acrylic is made of combustible materials and hence flammable. [1] [2] [3] The same information can be depicted in a normal. , storage room, flammable liquidLet me explain. studies are continuing to test the combustibility of A2L refrigerants. But while it can withstand some heat, it can also easily catch fire when exposed to an open flame. Just a spark is sufficient enough. combustibility — what's the difference. This test is typically performed on materials in passenger cars, trucks, and buses. These limits specifically apply to the concentration of chemical vapors in air. 8 toThe first two mean the same thing, but one is preferred. 2 sustained combustibility test. Flammable and combustible liquids should be segregated and stored separately from incompatible materials such as acids, bases, corrosives and oxidizers. NFPA 101 and NFPA 5000: Noncombustible Material. Generally, a material can be rated as extremely flammable, flammable, and non-flammable. Following Anderson (and further discussed by Gill & Zylstra 2005), flammability can be said to include ignitibility (how well the fuel ignites), combustibility (how well it burns) and sustainability (how long it burns). The formation of P,N-doped cellulose fibril and its influence on thermal degradation, flammability properties, and mechanism of the resultant composites are systematically examined in this study. doc Page 1 of 2 . DOT’s 49 CFR Rules for Class 3 and 4 Materials. This page titled 1. Physical properties of polymers handbook flammability. represented by a single value, a s several parameters are. Learn all about WHMIS and Flammability vs. 540. If you’re still a little confused, that’s okay. Once these issues have been addressed, the article can be renominated. Determination of Combustibility • UN Test N. Flammability limits are given in terms of fuel concentration (by volume) at a specified pressure and temperature. Now, let’s take a look at some common paints and their flammability vs combustibility (or lack thereof). MOC is higher using CO 2 for inertion, since CO 2 has a larger. Some examples of flammable liquids include common solvents like acetone, many paints, and alcohols such as methanol or the kind you might use to toast your love with in a few days. Once there is a thorough understanding of the pertinent flammability/ combustibility characteristics of materials processed, their extent, and duration – and once their hazardous Classes, Divisions, and Groups are established, then it becomes possible to select suitable electrical equipment TYPES. Stroup A ny material capable of burning with a flame is considered flammable. Examples of nonflammable materials include helium, glass, and steel. 1 Terminology: Fire Versus Flammability 42 5. Combustibility (which is what the question seems to be asking about rather than the the more technical "flammability") has little relationship to volatility. This is an important property to consider when a substance is used for construction or is being stored. This means that if the paint thinner comes into contact with a small spark, it will not explode or catch fire. Internationally, a variety of test protocols exist to quantify flammability. The good news is that once you know the rules of physical vs chemical, it becomes much more obvious. combustibility test L. 8°C (100°F) and below 93. Combustibility definition: The quality or state of being combustible. If a material melts, its phase changes, but not its identity. 2. Non-additive effects were observed in some flammability components of live foliage and litter, especially in the mixtures of C. 302)Detailed discussion concerning effects of fabric structure on FR, comfort and mechanical properties of cotton fabrics would be provided in this study. Part 4 of the BS 5803 standard details the insulation flammability test procedure that should be followed. Generally, any substance that is classified as flammable has a much lower ignition temperature, or flashpoint, compared to one that is classified as combustible. With such a high flash point, and even though it will burn, acrylic is not considered flammable by either the OSHA or WHMIS standards. As noted by Carpenter and Janssens (2005), one of the biggest obstacles to the use of the cone calorimeter for combustibility is the implementation of a classification system that does not disrupt the status quo. It will burn easily. This page titled 1. Flammability and combustibility are frequently used interchangeably but they are different chemical properties. Plastics, like all organic materials, will burn. A flammable or combustible material must normally reach its flash point before an. TTI increases from 34 s of the M0 to 60 s of M4, and from 40 s of the A0 to 52 s of A3, and TSR decreases from 203. Examples of non-combustible materials include steel, masonry, ceramics and certain insulating materials. According to the U. . a colourless flammable liquid that turns into vapour at 150-200ºC. gardless of amount . Texture. Z:COSE DOCSIIPPWritten ProgramsChemical Hygien e PlanFlammable and Combustible Liquids_CHP. One of the largest causes for loss in process industries for both equipment and life is fire. In general, a flammable liquid burns easier than a combustible. Air contains approximately 21% oxygen and therefore any material with an LOI of less than 21 will probably support burning in an open-air situation. Combustibility and Characteristics of Wood-Fiber Insulation Boards Prepared with Four Different Adhesives. In most of the aqueous solutions, these are poor conductors of heat and electricity. 5. 7 psia (101 kPa) with air of not less than 12 percent, regardless of the lower limit. com, 630-323-8750. 7 psi (101 kPa) of pressure and a temperature of 68°F (20°C) in accordance with ASTM E 681. Combustible liquids have a flashpoint at or above 100°F. The flammability of the live crown of plants of C. A good way to remember to use flammable over inflammable is that it is a simpler word, as is it’s opposite. Though PVC (polyvinyl chloride) is naturally fire-resistant. Flammable liquids have a flash point of less than 100°F. 2, Part III, section 32 of the UN RTDG, Manual of Tests and Criteria. The. Since the smoke generation of an air filter unit, as well as its combustibility, depends upon the nature and quantity of. Flammability is an innate idea of any material. TÜV SÜD’s state-of-the-art, ISO 17025 accredited flame-retardant testing labs can evaluate products and materials according to US and EU flammability requirements. Much depends on what the base of the paint is and. It is toxic by ingestion and inhalation and has a threshold limit value (TLV) of 50 parts per million (ppm) in. Lower Flammability (Explosive) Limits (LEL or LFL): The lowest percentage concentration at which a flash or flame can develop and propagate from the source of ignition when in contact with a source of ignition in a combustible material. GB/T 8626 Test method of flammability for building materials. Our Flammability Testing Services. boiling points c. Density and temperature are intensive, when you combine 2 gallons of water the temperature stays at 20 deg (it does not become 40) and the density stays at approximately 1g/ml. It should be kept away from open flames and heat sources such as burning cigarettes, lighters, matches, space heaters or any other potential ignition source, because if ignited, FPF can burn rapidly. Specifically, flammables will ignite at lower temperatures than combustibles when exposed to an ignition source. Here's a simple demonstration that illustrates the difference between a flammable liquid and a combustible liquid. Iron, for example, combines with oxygen in the presence of water to form rust; chromium does not oxidize (Figure 2). information on the combustibility of the material is the Safety Data Sheet (SDS). It is also important in processes that produce combustible substances as a by-product. 1. Flammability or inflammability means that something can be set on fire easily. know concerning all of that is that different agencies and organizations have different standards for determining what flammability is and what combustibility is. Flammability refers to a substance’s ability to catch fire and sustain a flame, while combustibility goes a step further, indicating the potential for a substance to undergo rapid combustion or explode. Much depends on what the base of the paint is and. The vaporization rate increases as the temperature increases. Flammability tests were also conducted on bark samples to estimate the resistance of the tree species to fire. 1% in air. Flash point provides valuable information to those who handle, transport, and store chemicals. Different dusts of the same chemical material will have different ignitability and explosibility characteristics, depend-ing on particle size, particle shape and moisture content. A material that has a flash point ABOVE 61ºC. The rich flammability limit is about 4. The UL 94 Standard provides a method for rating the ignition characteristics of plastic materials. Testing Methods. Flammable materials, whether solid, liquid or gas, can burn with a flame at ambient temperatures. That said, all workers have the potential to come across situations where flammable or explosive limits must be acknowledged. Combustibility has almost noting to do with volatility (other than in the trivial sense that things that are hard to vaporise are hard to set alight even if they are inherently flammable–like bitumen). As it was suggested earlier, the flammability can be minimized by spent. dichloroethane . UL94 flammability test includes the following 4 methods: 1. E136-22 Standard. Leather vs. Flammability of Kerosene. Decomposability showed no signs of coupling with any measure of flammability, except for a marginally statistically non-significant correlation with fire sustainability of fresh leaves (h). Read more. 2 Combustibility Non- combustible is a defined term in the BCA. There are four grades of flammability, where a liquid has to have a “flash point” of different degrees celsius or below. 10. There may be suggestions below for improving the article. Vertical burning test for UL94 V-0, V-1, and V-2 rated materials; 3. Choosing the Best Respirator for Wildfire Smoke. A clear distinction emerges between the properties ‘flammability’ and ‘ignitability’ by defining them in terms of temperature. Flammability vs. To explain the subtle difference between these substances: Flammable liquids will ignite and burn easily at normal working temperature, whereas combustible liquids are less volatile substances. Organic compounds are non polar that's why they are soluble in non polar solvent while inorganic are mostly polar so they are soluble in polar solvent. Liquids with high Combustibility and low flashpoint are those liquids that can be smelled. No new substances are formed. combustibility was performed in Carson City, Nev. 2. Combustibility : combustible: non-combustible: Boiling/Melting point: lower: higher: In general, the guidelines of this table hold true when comparing organic and inorganic compounds against each. Wood is organic, carbon-rich material that catches fire easily when exposed to a heat source. This satisfied the building industry where concrete, glass and steel were the main construction materials and flammability was an important factor in the fire. These fire and flammability standards are instrumental in the establishment of building codes, insurance requirements, and other fire regulations that govern the use of building. Table 1A. Under the Transportation of Dangerous Goods Regulations, liquids that have a flash point greater than 35°C are not included in Class 3 Flammable Liquids if they do not sustain combustion as determined in accordance with the sustained combustibility test referred to in section 2. 2 Interior finish flammabilityIf you’ve been using flammable and inflammable interchangeably, you’re probably wondering if you’ve even been using them right. There is no set definition of the word “paint”. Consider a pool of diesel fuel; if you were to. 1 A flame is a stream of the gaseous fuel and oxidizing agent involved in the combustion process that produces heat (including radiant energy and usually visible light, according to NFPA 921, Guide for Fire. These fire and flammability standards are instrumental in the establishment of building codes, insurance requirements, and other fire regulations that govern the use of building materials, as well as in defining the appropriate criteria for the storage, handling, and transport of highly flammable substances. 10. Examples of chemical properties include flammability, toxicity, acidity, reactivity (many types), and heat of combustion. Anderson [] proposed that flammability includes three components: “ignitability,” the delay on ignition; “sustainability,” the duration of combustion; and. plant-scale combustion rate; P = 0. displaces hydrogen from water. Burning stops within 10 seconds on a. Tack on the – able suffix and you get flammable. Class E – Small flame test duration of 15 seconds with less than 15 cm flame spread. Key Takeaways: Flammable materials are substances with flashpoints under 100°F, and combustible materials are substances with flashpoints over 100°F. 1 In addition, bamboo contains very few volatile oils. It can also burn the skin in high concentrations. 回答を翻訳 0 likesFlammability is a catch-all term to describe the reaction. 1 (4. They also have. Internationally, a variety of test protocols exist to quantify flammability. 1. The vapor burns, not the liquid itself. Since diesel fuel is both flammable and combustible liquid, then it also means that it is a fire hazard. 3 kPa. 7. In other words, they burn easily. Paper or wood can be ideal examples of combustible materials. While carbon monoxide can be a fire hazard in some situations, there are some other issues that you also need to know regarding its safety. The lower and upper flammability limits (LFL and UFL) for common compounds are shown in Table 1. Of the two terms, the older word for something capable of burning is. As safety is an important factor in making laboratory. 3b. Whereas uPVC cladding would ignite most of the directly exposed combustible material in an enclosed area in around 10 minutes or even less, Sentinel. Remember that we mentioned that sugars are a combination of hydrocarbons and some oxygen. It seems counterintuitive that a highly flammable substance like Styrofoam can go in the microwave. The ratings achieved are used in building codes. There may be suggestions below for improving the article. Liquids with lower flash points ignite easier. The use of the cone calorimeter as a test for combustibility has also been investigated (Carpenter and Janssens, 2005). Fire Safety. Combustion heat or calorific value is calculated on the basis of the measured. 2. 3°C (200°F). However, if the proposed draft label has such a claim, the reviewer must check to see that the terms “Extremely Flammable” or “Flammable” do not appear in the Physical or Chemical Hazards section of the proposed label. To receive the classification needed to get insulation products to market, they also need to undergo testing for combustibility, heat levels, flame spread and smoke release. the science of measuring the HEAT of chemical reactions or physical changes. The lack of independence between the four components adds to the complexity of quantifying flammability and of developing a standardized method for doing so. This. 54, 179–184, (1973). Though similar, there are differences in how these two Federal agencies define and describe this term. Photo: Govmark. (2) The authors consider that this device increases safety during this potentially hazardous procedure by. An example of this might be a substance such as propane. A horizontal burning test, where burning stops before 100mm. Learn with flashcards, games, and more — for free. English term or phrase: flammability vs. The testing gas is determined to be ignited, if the maximum flame propagation included angle from the point of ignition to flame propagation along the wall of the bottle (defined as α) is larger than 90°, which was shown in Fig. 8°C) or higher, also when tested by closed‐cup methods. Organic compounds form covalent bonds. 1:1994 (R2016) Valid from 21/03/1994. To understand what combustible materials are, you first need to understand combustion. It keeps the gasoline clean and, under normal conditions, keeps vapors within the can. Petroleum ether autoignition temperature is from the SDS. Environ. 2 While the GHS. Assess risk exposure for flammability potential of combustible gas, vapor or solids with common tests for flammability testing and standards. Labelling should either use the word “flammable” or an easily recognisable flame symbol. ASTM's fire and flammability standards are involved in the testing and evaluation of the ignition, burning, or combustion characteristics of certain materials. Vodka's combustibility can be explained by the science of alcohol and its flammability. to determine if that material is explosive or extremely flammable (see WARNING below). 1. As such, those plastic materials used in. ACRYLITE® Resist 45 acrylic sheet has a self ignition temperature of 950 degrees Fahrenheit, a smoke density rating of 3. 68 combustibility test L. The light hydrocarbon fuels, for example, are seen to produce flammable mixtures at near ambient temperatures and thus, for fire safety, require protection from sparks, flames and. 3 This method could involve the combustion of highly flammable materials and theThe aims of this study are to ascertain the flammability and combustibility of holm oak (Quercus ilex L. Flammability tests for external cladding on buildings. , a small spark will ignite it), as. A formula to estimate forest fuel flammability index (FI) is proposed, integrating three species flammability parameters: time to ignition, time of combustion, and flame height. If a material burns in air, it is combustible. A chemical property describes the ability of a substance to undergo a specific chemical change. 9. 4. It is also known as combustibility or flammability, which describes a substance's ability to react with oxygen and release energy in the form of heat and light. As a result, it becomes combustible. A different test logic is suggested to address these impediments: one toSuch feedbacks can occur when a flammable weed invades a less fire-prone ecosystem. combustibility: 1 n the quality of being capable of igniting and burning Synonyms: burnability , combustibleness Types: flammability , inflammability the quality of being easily ignited and burning rapidly Type of: quality an essential and distinguishing attribute of something or someoneFlash Point is a term used by the US EPA when characterizing an Ignitable Hazardous Waste and the US DOT when classifying a Flammable or Combustible Liquid. Flammable is a substance which under normal conditions has the ability to catch fire with a minimal ignition source (such as a spark). It can easily ignite or catch fire if it is near or comes. 4A: Methods and Flammability is shared under a CC BY-NC-ND 4. It refers to the ability of the respective substance to burn or ignite, causing combustion or fire. When heated, it will give off fumes that can be ignited. 04 ºF, while it is termed as a combustible material if it has a flashpoint higher than 100. Flammability codes: the basics. 10. 26 m 2 m −2 of the A0 to 125. Part 1 is a screening test in which an unbroken, 250mm long powder train, is ignited at one end with a gas burner and observed. 1: For non-combustibility AS 1530. Leather, in its natural state, is not easily flammable. These flammability tests occur in a burn room which contributes to the measurement of heat release, smoke release and opacity, combustive gas release and total mass loss. Sample Holder for DIN4102 Flammability Class B1 Vertical Shaft Furnace. 10. 265 11. The NFPA. The main difference between flammable and combustible liquids is the flashpoint, which refers to the lowest temperature at which the vapors generated by a liquid turn into a flammable gas and can ignite. Add a comment. Numeric values for Class B are between 25 and 75. 71 8. Let us understand the meaning of combustible and flammable in simple language. The flammability and sustained combustion of ethanol/water mixtures and commercially available alcoholic beverages are examined in detail in this study. In general, a substance is considered flammable if its flash point is less than 100°F (37. Unalloyed aluminum. IS YOUR DUST COMBUSTIBLE? When looking to protect against a dust explosion, it is critical to know the Kst value of your material. 44°C) (source). Let’s take a closer look. Section 12. 3 of the UN Recommendations – the L. 3 of Chapter 2. Add a widget to your website or intranet so your workers can quickly find answers to their health and safety questions. Inflammable and flammable are used to mean the same thing. Decomposability showed no signs of coupling with any measure of flammability, except for a marginally statistically non-significant correlation with fire sustainability of fresh leaves (h). Combustible material means a material that, in the form in which it is used and under the conditions anticipated, will ignite, burn, support combustion or release flammable vapors when subjected to fire or heat. Further fire class Cfl corresponds to the previous national building materials fire classes for “fire-retardant” floor coverings. Combustibility- ignites with some effort (wood/paper) Reactivity- 2 or more substances combine to make new. Since the 1960s, PFA members have been researching and. The main difference between flammability and combustibility is the flashpoint. NFPA has six classes of flammable liquids. Vertical burning test for UL94 5V rated materials; 4. However, this definition is ambiguous because both combustibility and fire hazard are complex and depend on many parameters related to the material, its end. Organic compounds catch fire when heat is given but inorganic compounds are inflammable. Familiar examples of physical properties include density, color, hardness, melting and boiling points, and electrical conductivity. Synthetic Materials When it comes to flammability, leather generally outperforms many synthetic materials. 5"(filling/course) is suspended vertically in a holder and subjected to an igniting gas flame along the bottom edge for three seconds. Flammability diagrams show the control of flammability in mixtures of fuel, oxygen and an inert gas, typically nitrogen. Some are commonly found in the outside world, in the home, or even in the classroom. ”. 8 C and below 93. at 130 °F; or any liquid flammable material having a vapor pressure exceeding 40 p. . Label the axes in the diagram. These cellulose fibrils are subsequently introduced to high-density polyethylene (HDPE) to improve flame retardancy. If the draft label has no claim of non-flammability, skip this section. s. 118". The use of plastic building materials in commercial and residential construction has dramatically increased due to improved plastic material performance, efficient use of technologies in new applications, and the need for lightweight, durable materials for insulating and construction purposes. It is typically used to describe the behavior of materials. Class 1 Liquids are separated into the following three categories: Class 1A - Liquids that have flashpoints below 738 F (22. - the higher the LOI the lower the flammability. the flammability of a polymer is an interaction of pyrolysis, ignition, combustion, . Necessary combustible dust testing, liquid flammability testing and other flammability hazard testing are defined by the unique setting of each work environment. Class IB Flash point below 73 F, boiling point at or above 100 F . A combustible dust is any material (finely divided solid particles) that has the ability disperse in air and catch fire and explode when exposed to an ignition source. Combustibility and flammability was a Natural sciences good articles nominee, but did not meet the good article criteria at the time. The upper and lower flammability limits can be reported as either a percentage (%) or as a mass per unit volume (g m −3). The difference between flammable and combustible is that they are more dangerous than combustible substances as they can catch fire and burn easily at normal room temperature. 5 to 2. Combustible liquids have a flashpoint above at or above 37. flammability ____ physical change – does not alter the chemical identity of a substance. Flammability and ignitability. It contains a large number of chlorine ions in the molecular structure and these are particularly difficult to break off when exposed to heat. as a test for combustibility has also been investigated (Carpenter and Janssens, 2005). 3. "Liquids" excluded by NFPA from the definition of "flammable liquid" are those which have a vapor pressure:. The chemistry of polyurethane foams and. Flammability labelling should be indelible, easily legible and visible, on the inner (primary) and outer (secondary) packaging.