Worker safety is of the utmost importance and there can be no compromise in equipping workers with the proper personal protective equipment.
Independent international organizations and regulations have developed guidelines and standards that health and safety officials must follow to ensure the quality of personal protective clothing, leading to better levels of safety for workers.
risk assessment
It is important to understand the level of risk involved and which type of FR clothing will be the best for the workforce.
One way to do this, firstly do a thorough risk assessment. And then based on the assessment, select the types of fabrics that will be best suited for employees.
FG clothing selection
Different countries follow different norms and standards for tests and certifications
The second step to selecting the right type of FG clothing is to ensure that it meets all the safety standards and has the required certifications after clearing the tests. The question is – What tests do FR garments need to pass for certification?
Different countries follow different norms and standards for tests and certifications. Following are a few most commonly adopted tests for FG garment certifications.
Tests Required For FR Garment Certifications
The following segments provide a brief overview of commonly cited standards and test methods for testing personal protective clothing (PPC) against thermal hazards associated with flames, heat, arcs, lightning, molten splash, chemicals, etc. The most tests are:
- Flame resistance test
- Flash fire exposure
- Exposure to an electric arc
- Exposure to electric arc and flash fire (protective clothing against rain)
- Protection against heat, flames, and thermal risks (European standards)
- European standards (EN)
However, ISO 11611: 2015 specifies two tests with performance requirements for FR garments certification: Radiant Heat and Flame Spread Test.
Radiant heat:
Radiant heat tests can be of different levels depending on the fabric used and the safety provided by the FR clothes.
- Class 1 is protection against less dangerous welds, techniques, and situations, resulting in lower levels of projections and radiant heat.
- Class 2 is protection against more dangerous welds, techniques, and situations, resulting in higher levels of projections and radiant heat.
Flame Spread heat:
Similar to radiant heat, the flame spread test is also of different levels depending on the safety and fabric used. It tests the time taken by the fabric to catch flame under different conditions.
- A1 – When exposed to flame, the fabric should resist surface ignition for 10 seconds.
- Electrical Resistance (EN 1149):
This test ensures that if the fabric is exposed to voltage or electrical current the fabric should have an electric resistance capacity of higher than.
EN ISO 11612: 2015 – Requirements For Protection Against Heat And Flame
Limited Flame Spread Test:
This test also has different standards to check the resistance capacity of the FR garments when exposed to limited flame.
- The garment should not allow part of the lower limit of a flame to reach the top or vertical edges.
- No specimen should produce hot or molten debris.
- The average value of the time after the flame must be less than 2 seconds for A2 and less than 10 seconds for A1.
- The average value of the persistence time must be less than 2 seconds for A2 and less than 10 seconds for A1.
Convective Heat Test (Level 1 to 3):
When exposed to heat via a convective medium the time taken to reach a temperature rise of 24 ° based on different levels should be:
- 4 to 10 seconds for B1 level
- 10 to 20 seconds for B2 level
- 20 seconds and more for the B3 level
Radiant Heat Test (Level 1 to 4):
When exposed to direct heat the resistance capacity of the fabric based on different levels should be:
- Less than 20 seconds for C1 level
- 20 – 50 seconds for C2 level
- 50 – 95 seconds for C3 level
- 95 seconds and more for the C4 level.
Molten Aluminum Splash Test (Levels 1 to 3):
When exposed to molten aluminum splash, the membrane underneath the fabric should not distort until the following amount of splash does not surface the fabric:
- 100 g <200 grams, for D1 level
- 200 <350 grams, for D2 level
- 350 grams and more for the D3 level
Molten Iron Splash Test (Levels 1 to 3):
When pouring molten iron metal on the fabric, the membrane underneath the fabric should not distort until the following amount of iron splash does not surface the fabric:
- 60 <120 grams, for E1 level
- 120 <200 grams, for E2 level
- 200 grams and more for E3 level
Contact Heat Test (Level 1 to 3):
When exposed to direct contact heat, the fabric should not ignite until:
- 5 <10 seconds, for F1 level
- 10 <15 seconds, for F2 level
- 15 seconds and more for the F3 level
EN ISO 11416: 2015 – Requirements For Protection Against Heat And Flame
Protective clothing according to EN ISO 14116 may consist of several separate garments or a single garment with one or more layers. All assemblies that require compliance with this standard must achieve a limited flame spread index of 1, 2, or 3.
- Index 1: No flames on the top or side edge, no burning debris, and no transfer should propagate from the charred area to the intact area. The formation of holes is possible under this index.
- Index 2: No flames on the top or side edge, no burning debris, and no transfer should propagate from the charred area to the intact area. Hole formation is not possible with this index.
- Index 3: the requirements are the same as for index 2, but the flame time of each sample must not exceed 2 seconds.
ASTM D7138 Requirements For Protection Against Heat And Flame
- Thread Melting Resistance Test: a thread or the yarn used in clothing must be of flame-retardant fiber and not melt at 500 DF.
- Vertical Flame Resistance Test: When exposed to flame for 12 seconds, the fabrics of the garment should be able to:
- Self-extinguishing (after flame) in 2 seconds or less
- Exhibit damage (char length) of 4 inches or less
- Should not melt or sink
- The fabric must meet these standards after 100 industrial wash cycles.
Tests are to be carried out on each material of the garment including all layers (for insulating clothing).
Heat and fire-resistant protective clothing
Heat and fire-resistant protective clothing is intended to protect the user from risks that may cause skin burns or any serious burn injuries. The elements can be made of one or more materials. Generally, there are two steps to assess the materials that can be used in these types of clothing. Fabrics are first tested to assess their ability to limit the spread of flames.
They are then tested to determine the rate of energy transferred through them when exposed to a particular hazard. The above-mentioned test methods are used in these two steps. The test methods are chosen depending on the nature of the potential hazards and the intended end use of the FR garment.
