The Beginner’s Guide to Heat Resistance: 6 Things to Consider
You know the feeling.
It’s a few seconds after the initial pain of yanking your hand back from touching something hot.
You start shaking your hand, trying to flick the pain off your skin.
As the pain starts subsiding, it’s replaced by a pulsation under the skin like the burn has a tiny heartbeat.
That type of burn could be minor, leading to some redness and inflammation of the skin. But burns can be much more severe, resulting in infection or nerve damage.
It’s an awful feeling that you could have prevented with the right heat-resistant protection.
How Do You Select the Right Protection?
By knowing what questions you need to ask. That’s the aim of the Beginner’s Guide to Heat Resistance.
1. How are Heat Ratings Measured?
Let’s start with some background information by looking at how we measure heat ratings.
North American Standard (ASTM F1060):
As we covered in our heat resistance infographic, this test measures the conductive heat resistance of a material to determine its thermal insulation properties for contact with hot surfaces.
The glove’s rating is determined by the highest contact temperature where time to second degree burn is over 15 seconds and time to pain is over 4 seconds.
The standard rates the material between level 1 (under 176°F) and level 5 (608°F). Note: While the test stops at 608°F, the glove may have higher thermal protection.
The European Standard (EN 407:2004):
This standard includes six thermal tests: burning behavior, contact heat, convective heat, radiant heat and the small and large splashes of molten metal.
We are focusing on the North American standard, but Hannah Althorpe’s article Handling Extreme Temperature is an excellent resource on the European standard.
2. How Hot is It?
Now you know how heat-resistant gloves are measured, but what about the thermal temperature of the items you’re touching?
It’s important to be accurate with the reading (don’t try to estimate).
The easiest way to do this is with an Infrared Thermometer.
This step is critical for two reasons:
- If you overestimate the heat of an object to “play is safe,” you may get a glove has too much insulation. This makes the glove bulky and will limit dexterity.
- By underestimating the heat of the object, you’re putting yourself at risk for burns. You may also have to spend more money due to lost-time injuries.
3. What is the Most Heat-Resistant Material?
There are two main options for heat-resistant gloves:
Terry knit and synthetic material.
Selecting the right material depends on the heat of the thermal temperature.
The best option for heat resistance below 450°F is natural materials like terry cloth.
The terry is “looped” when knitted which traps air to create an excellent insulator.
The protection terry cloth offers may not seem like much, but who hasn’t used a dish cloth to take something out of the oven after misplacing an oven mitt?
The dish cloth and a terry-knit glove use the same material. As long as there aren’t risk of cut or puncture this inexpensive style of glove is a great option.
Synthetic materials like Kevlar® are the best option for heat-resistance for temperatures over 450°F .
Terry fabric begins charring at these higher temperatures, so synthetic materials work well as a shell over top of the terry lining.
A neoprene glove is the best bet for protecting against steam or hot liquids. This synthetic rubber resists degradation and has a burning point of 500°F.
4. What are Your Work Conditions?
There is not a single perfect heat-resistant work glove. Every industries have conditions to consider when choosing the right glove for your workplace.
The Type of Heat:
- Dry vs. Moist: The difference between a string-knit or a neoprene-dipped glove.
- Thermal vs. Ambient: Is it through direct contact or the temperature in the room?
- Is there open flame or spark?: If so, you’ll need a glove treated with a fire-retardant chemical.
- Are there other hazards? Heat may be the primary concern but in industries like metal stamping there may be risk for cut or puncture. Synthetic fibers like Kevlar® provide good cut protection. Silicone palm coating like Temperbloc™ can increase puncture resistance and provide grip.
5. Are There Other Factors to Consider?
We’ve covered the importance of knowing the temperature, identifying working conditions and selecting materials. But there are a few more things to consider:
- How heavy is the item? A fifty pound piece of steel needs a lot more contact to move than a five pound piece.
- Is there cool down time? The glove will trap heat. If there isn’t time for it to cool down between uses, the user will begin to feel heat through the glove. If the application occurs on a regular basis, a glove with more insulation is required.
- How long will you be holding onto the item? The longer you handle an item, the more heat will transfer from the object to your PPE.
- How important is dexterity? The more insulation a glove has, the less movement your hand will have. Try on a few gloves in the required heat protection range to find the one that allows for the most movability.
6. Find a Balance:
By thinking about the above factors you can select the correct type of PPE for your industry.
Finding the best protection is a balancing act, but it doesn’t have to be an inconvenient trade-off between comfort and protection.
Now that your hands are safe, what about your arms?