Below is a list of the some of the key terms used in the flame-resistant industry.
Flame Resistant (FR) – A fabric or product that resists ignition and self extinguishes after removal of the ignition source.
Flame Retardant – A chemical treatment applied to a flammable base fabric that gives it FR properties.
Inherent – An FR fabric that is made of fibers that are flame resistant due to the chemical structure of the fiber and which has not been chemically treated.
Treated – An FR fabric that takes a flammable fabric and treats it with a flame retardant chemical.
Vertical Flame Test – A basic test that determines whether or not a fabric is FR by measuring how much of the fabric is consumed after 12 seconds of flame exposure.
Char Length – A measurement of the damaged fabric after the Vertical Flame test.
General Fabric Terms
Aramid – The chemical family of FR fibers like Nomex® (meta-aramid) and Kevlar (para-aramid).
Nomex – The brand name for the meta-aramid produced by DuPont™.
Kevlar – The brand name for the para-aramid produced by DuPont™.
Modacrylic – A generic name for a type of inherently FR fiber (e.g., used in Protera® and Tecasafe® plus).
Lyocell – A cellulose fiber made from dissolving wood pulp (a type of rayon).
PBI – Short for the polymer Polybenzimidizole. It is an inherently FR fiber made by Celanese, Inc.
FRC – Flame-resistant clothing.
OSHA – The Occupational Safety and Health Administration
NFPA – The National Fire Protection Association
ASTM International – The American Society for Testing and Materials
NESC – The National Electrical Safety Code (safety standards for electric utilities)
ANSI – American National Standards Institute.
CSA – Canadian Standards Association.
CGSB – Canadian General Standards Board.
NFPA 70E – The Standard for Electrical Safety in the Workplace.
NFPA 2112 – The Standard on Flame-Resistant Garments for Protection of Industrial Personnel Against Flash Fire.
ANSI 107 – The Standard for High Visibility Safety Apparel.
CSA Z462 – Workplace Electrical Safety (the NFPA 70E of Canada)
CGSB 155.20 – Workwear for Protection Against Hydrocarbon Flash Fire (the NFPA 2112 of Canada)
CSA Z96 – High Visibility Safety Standard (the ANSI 107 of Canada)
Electrical Hazard Terms
Arc Rating – The value for fabrics that describes their performance under exposure to an electrical arc discharge. Testing determines when the amount of exposure results in a 50% probability of causing the onset of second-degree skin burn. The arc rating is expressed in cal/cm². It can be either an ATPV or an EBT.
ATPV – The Arc Thermal Performance Value of a fabric shown in cal/cm².
EBT – The Energy of Breakopen Threshold. The cal/cm² at which the fabric breaks open before it reaches its ATPV.
HRC – Hazard Risk Category. A term used specifically in NFPA 70E. If the 70E table is used, each specific task listed establishes one of five HRC category requirements for the protective clothing and PPE to be worn while performing that task. Each category outlines the minimum arc rating (cal/cm²) for the FR clothing and other PPE required.
Flash Fire Terms
TPP – The Thermal Protective Performance of a fabric. It is the amount of heat it takes to pass through the fabric and cause a second-degree burn. CGSB 155.20 requires a fabric to have a minimum of 6 cal/cm² when tested with a spacer.
Manikin Test/Body Burn– A simulated flash fire test using an instrumented manikin to calculate the estimated percentage of second and third degree body burn after three seconds of exposure. NFPA 2112 requires the percentage to be below 50%.
HTP – The Heat Transfer Performance of a fabric, or the amount of heat it takes to pass through the fabric to cause second-degree burns based on the skin burn curve. NFPA 2112 requires a fabric to have a minimum of 6 cal/cm² when tested with a spacer and 3 cal/cm² in contact.