Khas Industries

Heat Resistance In Protective Gloves

TESTING GLOVE SAFETY: (THERMAL SAFETY)

Many people are worried about whether their gloves will be able to provide safety against thermal hazards. One way to answer this is by looking at whether or not these gloves have been tested for heat resistance by comparing the scores on the EN 407 standard which is an international standard measuring a glove’s ability against thermal risks. There are six tests conducted to determine this and are explained in more detail below:

1) RESISTANCE TO FLAMMABILITY:

WHY IT MATTERS:

This measures the inherent fire resistance of the material with which the glove is made.
This matters because fire can spread quickly and have fatal consequences if the material is easily flammable.

TEST DETAILS:

This test is conducted by exposing the glove material to a flame for 3 seconds and measuring the time it takes for both the fire and the glow to fade away. The lesser time it takes for this to happen the better the fire resistance properties of the material. The table below demonstrates how this is qualified. If the glove seams come apart after 15 seconds it will be given a rating of 0 which means the glove has failed the test.

After Burn Time (seconds) After Glow Time (seconds) Rating
Under 20 Seconds Infinity 1
Under 10 Seconds Under 120 Seconds 2
Under 3 Seconds Under 25 Seconds 3
Under 2 Seconds Under 5 Seconds 4

 

2) CONTACT HEAT TEST:

WHY IT MATTERS:

This test is important as it determines how quickly your hands will feel the heat when you are holding a hot object.

TEST DETAILS:

It is conducted by exposing the outside of the glove material to a level between 100C and 500 C and measuring the temperature increase inside the glove. The increase must not be more than 10 degrees in 15 seconds for the glove to pass each level. For example, if the temperature inside the glove does not increase by more than 10C in 15 seconds when the outside is exposed to 100C the glove achieves level 1. The below table gives a guideline on the rating for each temperature level the glove is exposed to:

Plate temperature

 (Outside part of glove)

Duration

(Glove resists 10 C increase inside)

Rating

 

100 >15 seconds 1
250 >15 seconds 2
350 >15 seconds 3
500 >15 seconds 4

An important thing to note is that the glove will only be given a level 3 rating on this test if it has also achieved a level 3 rating on Test 1 (Flammability Test). Otherwise it will only achieve a maximum rating of Level 2.

3) CONVECTIVE HEAT TEST:

WHY IT MATTERS:

Similar to contact heat, this test also measures how quickly the inside of the glove achieves a certain heat level but instead of putting the glove in direct contact with the heat source, this test measures the temperature rise from convective heat.

TEST DETAILS:

A gas flame is exposed to the outside of the glove and the time taken for the inside of the glove to rise by 24C is then measured. Level 3 on the Flammability test must be achieved in order for this test to be conducted.

Seconds to Raise Temperature by 24 C Rating
Less than 4 1
Less than 7 2
Less than 10 3
Less than 18 4

4) RADIANT HEAT TEST:

WHY IT MATTERS:

Similar to test 3, the radiant heat test determines how long the glove can prevent an increase in temperature on the inside part of the glove from electromagnetic radiation.

TEST DETAILS:

The outside of the glove is exposed to a radiant heat source and the increase in temperature on the inside is measured.

Seconds to Raise Temperature by 24 C Rating
Less than 7 1
Less than 20 2
Less than 50 3
Less than 95 4

5) SMALL SPLASHES OF MOLTEN METAL:

WHY IT MATTERS:

This test is important because it measures how resistant your gloves are to small pieces of fiery hot metal. If gloves are not worn, these splashes can easily burn your skin.

TEST DETAILS:

Small drops of a molten metal like copper are poured on the outer layer of the glove on both the palm and back of the glove and the number of drops needed to cause an increase in 40C on the inside of the glove is measured. The higher the number of drops the greater the resistance as indicated below.

# of Drops to Raise Temperature by 40 C  

Rating

Less than 10 1
Less than 15 2
Less than 25 3
Less than 35 4

6) LARGE SPLASHES OF MOLTEN METAL:

WHY IT MATTERS:

Similar to test 5, this test measures resistance to large drops of molten metal.

TEST DETAILS:

Instead of the number of drops to cause a 40C rise, this test measures the amount of molten metal needed to damage or puncture the glove. A PVC film is under the glove to simulate skin and the amount of molten metal needed to damage it gives the protective rating to the glove. The table below provides an illustration of the different levels.

Amount of Molten Metal needed Rating
30g 1
60g 2
120g 3
200g 4

 

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