2024-10-25 12:36:48
What are the grading standards for flame-retardant workwear
Flame retardant workwear is divided into three grades, namely Grade A, Grade B, and Grade C. The classification of these levels is mainly based on their different requirements for thermal protection coefficient and flame retardant performance standards. For example: GB8965-98, GA10-91, EN531, EN497, NFPA2112, GB/T17591-2006, and so on.
A-level: For A-level flame-retardant workwear, the requirements for flame-retardant A-level fabric are that the duration of continuous combustion and smoldering should be less than 2 seconds, the length of damage should not exceed 5 centimeters, and there should be no melting or dripping phenomenon.
The definition and requirements of flame-retardant A-level fabrics are mainly based on China's flame-retardant fabric standard GB/T 17591-2006 and protective clothing (flame-retardant clothing) standard GB8965.1-2009. These standards have clear regulations on the performance of flame-retardant fabrics, aimed at ensuring that the fabrics can quickly extinguish when exposed to a fire source, reducing harm to the human body.
① Continuation and smoldering time: The continuation and smoldering time of flame-retardant A-level fabrics should be less than 2 seconds, which means that the fabric can extinguish itself in a short time after coming into contact with a flame, reducing the duration of flame combustion.
② Damage length: The damage length should not exceed 5 centimeters. This requirement ensures that the degree of damage to the fabric during combustion is controlled within a small range, avoiding safety hazards caused by large-scale damage. No molten dripping phenomenon is allowed: This requirement further strengthens the safety of the fabric, preventing the dripping of molten substances during the combustion process, which can cause secondary damage.
B-level: Requires less than or equal to 75SDR. This standard is used to evaluate the amount of smoke generated by materials during combustion and is another important indicator for measuring material safety.
① It needs to be greater than or equal to 32.0%. This standard measures the minimum oxygen concentration required for a material to maintain combustion under specific conditions, and is an important indicator for measuring the flame retardant performance of materials.
② The combustion time should be less than or equal to 30 seconds, and the combustion height should be less than or equal to 250mm. This standard evaluates the flame retardancy of materials by simulating their combustion behavior when ignited vertically.
③ It needs to be less than or equal to 75SDR. This standard is used to evaluate the amount of smoke generated by materials during combustion and is another important indicator for measuring material safety.
C-level: The strictness of the indicators such as ignition time, smoldering time, and damage length of C-level flame-retardant workwear is relatively low, such as ignition time ≤ 5s, smoldering time ≤ 5s, and damage length ≤ 150mm.
The classification of these levels aims to ensure that different types of flame-retardant workwear can meet the safety requirements of different work environments, thereby effectively protecting workers from the harm of flames and high temperatures.