For more information about a comparison between the flash point and the LTL, please see the article “Evaluating the flammability hazard of liquid vapors” in our Winter 2012 Process Safety newsletter.

Inflammabilitymeaning

Data acquired from testing can be used to implement proper safety procedures and designs to help minimize the chance of an explosive event in your process.

Pressure relief sizing is just the first step and it is critical to safely handle the effluent discharge from an overpressure event

Flammabilityin a sentence

Closed cup flash point testing is conducted inside a sealed vessel where the ignition source is introduced periodically into the vapor space of the vessel. As a result, the substance is minimally exposed to the elements outside of the vessel, which can have an interfering effect on the results of the test. This, in turn, also leads to lower flash points compared to open cup flash point methods, because the heat and flammable vapors are trapped inside. Because it is lower, the flash point is also safer for widespread use, and as such is more generally accepted.

Depending on material properties, testing can be performed to determine the autoignition temperature using one of these listed standards:

Flammabilityexample

Other Testing - At FAI, we have an extensive knowledge regarding the design and development of specialized tests and test apparatuses. We continue to expand our testing capabilities and push the limits for testing conditions.  As a result, we are able to offer solutions for scenarios not typically quantified by standard test methods.

Facility modeling software mechanistically tracks transport of heat, gasses, vapors, and aerosols for safety analysis of multi-room facilities

Low thermal inertial adiabatic calorimeters specially designed to provide directly scalable data that are critical to safe process design

To help assess your risk exposure by characterizing the flammability potential of your combustible gas, vapor or solids, the following is a list of the most common tests, in addition to flash point and AIT, that are performed for flammability hazard characterization. Specialized testing can be also performed to more closely match your process conditions and thereby better gauge your risk.

Flammabilitysynonym

A good flammability testing regime will take into consideration the many different variables that affect the flammability of a specific chemical: oxidizing environment, temperature, pressure, ignition energy, size and geometry of the vessel, gas composition, etc. There are a variety of pressure vessels varying in size and geometry to use for flammability testing purposes dependent on the particular need.  The choice (spherical, cylindrical, large, small, glass, steel, etc.) depends on the particular test design. A well-defined ignition source is also necessary, as is a robust data acquisition system for monitoring pressure and temperature.

The all too frequent occurrence of fires and explosions in the process industries that use flammable materials is typically the result of a variety of factors including a flammable or explosive mixture being present in the vapor space, lack of knowledge of the properties of the chemical’s inherent safety implications, and/or inadequate safety procedures.

In order to minimize the risk of fire or explosion, it is important to evaluate the flammability characteristics of the material to understand key characteristics such as the lower flammability limit, upper flammability limit, limiting oxygen concentration and deflagration index.  Simply put, these are defined as:

Flammabilitypronunciation

FATE™ (Facility Flow, Aerosol, Thermal, and Explosion) is a flexible, fast-running code developed and maintained by Fauske and Associates under an ASME NQA-1 compliant QA program.

Flammabilityfacts

The flash point is the minimum temperature at which vapors given off by a liquid pool or solid layer form an ignitable mixture with air.  Flash point testing is used to assess the relative flash-fire hazards of handling and processing liquid and solid materials. Results from this test, in conjunction with vapor pressure or boiling point tests, will help characterize a liquid as either being flammable or combustible based on the criteria of organizations such as the NFPA, EPA, OSHA, or UN.  Characterization of liquids using the flash point test will provide information on the proper packaging and shipping group for transportation purposes, in addition to storage and handling requirements.

A certain concentration of vapor in the air is necessary to sustain combustion, and that concentration is different for each flammable liquid. The flash point of a flammable liquid is the lowest temperature at which there will be enough flammable vapor to ignite when an ignition source such as a flame is applied into the vapor space. Unlike flash points, the autoignition temperature does not use an ignition source. In other words, the autoignition temperature is the lowest temperature at which a volatile material will be vaporized into a gas which ignites without the help of any external flame or ignition source, but instead, uses heat to commence the combustion reaction. As a result, the autoignition temperature is higher than the flash point temperature.

Safe storage or processing requires an understanding of the possible hazards associated with sensitivity to variations in temperature

For more information regarding your specific testing needs and our industrial safety management services, please contact:  info@fauske.com, 630-323-8750

Software for emergency relief system design to ensure safe processing of reactive chemicals, including consideration of two-phase flow and runaway chemical reactions

Accounting for these variables can result in test data that are much more applicable to your specific process than information taken from literature.  Experts are happy to have a discussion with you about your flammable hazard concerns and work with you on designing tests that get you the information you need.  The goal is to provide you with specific data that corresponds to your process - not just meaningless data.

Flammabilityphysical or chemical

Depending on material properties, testing can be performed to determine the closed or open cup flash point using one of these listed standards:

The autoignition temperature (AIT) is a flammable property defined as the lowest temperature environment at which a gas or vapor will spontaneously ignite without a distinct/localized ignition source such as a spark or flame. It is helpful to know the autoignition temperature if chemicals are being handled or processed under elevated temperature and/or pressure conditions.  This flammability property is dependent on numerous factors including pressure, temperature, oxidizing atmosphere, vessel volume, and fuel/air concentration among others.  Therefore, it is important to characterize the autoignition hazard at as close to your process conditions as possible.

A variety of different flammability tests can be performed to allow for determination of these characteristics, and the understanding of these conditions is essential when implementing proper safety practices.

Autoignition temperature tests are performed by placing the substance in a half-liter vessel inside a temperature-controlled oven. The temperature of the vessel is then adjusted until the lowest temperature at which the material spontaneously ignites in air is determined.

It is imperative to fully characterize the flammability hazards of chemicals because the use of the flash point by itself may not always be sufficient in providing proper safety precautions to avoid flammable temperatures when assessing the hazards of flammable liquids.  Even the use of a safety margin with the flash point value may not always be adequate to protect a given system.  LTFL testing allows for accurate assessment of the temperature at which there is sufficient vapor for flame propagation, and enables design of the correct safety margin.

When conducting flammability testing, it is important that clients communicate what data is being sought so that testing can be properly designed in order to determine the necessary flammability property of a chemical mixture.

Flammability meaningin chemistry

There are a variety of pressure vessels varying in size and geometry to use for flammability testing purposes dependent on the particular need.  The choice (spherical, cylindrical, large, small, glass, steel, etc.) depends on the particular test design. A well-defined ignition source is also necessary, as is a good data acquisition system for monitoring pressure and temperature.