What is Flame Retardant Plastic?
Breathe in, do you smell it? The smell of burning plastic? Many of our everyday products need plastic that is resistant to burning. Whether it is an electrical part, automotive part, or another part that might experience extreme heat, reactive chemicals, or an open flame, the durability of your plastic and its flame retardant properties are important to identify before you end up with the smell of burning plastic.
Some types of plastic are organically more flame retardant than others. While others that are more flammable, can still incorporate additives to increase its flame resistance. Of course, it is necessary to consider that at a certain point additives that increase flame retardance begin to change other properties of the plastic that might not be the desired outcome for your product. Consulting your plastics engineering expert personally, is the best way to end up with the most functional and efficient plastics choice for your specific product.
What are the Different Flame Retardant Ratings?
Naturally occurring, some plastics are flame retardant (score V-0 or above – see below explanation). Some of these include, PVC, ABS, PBT, PP, TPE, PEEK, etc.
Internationally recognized as the standard test for flame resistance in plastics is the UL94. Depending on how the plastic tests it will be categorized into one of the following categories starting with the least flame retardant and continuing to the most flame retardant. Plastics that score V-0 and above are considered flame retardant:
HB Horizontal Burn; Slow burning on a horizontal part. These plastics burn a lot.
V-2 Vertical Burn; Burning stops within 60 seconds, Flaming drips ARE allowed.
V-1 Vertical Burn; Burning stops within 60 seconds, NO flaming drips are allowed
V-0 Vertical Burn; Burning stops within 10 seconds, NO flaming drips are allowed
5VA Surface Burn; Burning stop within 60 seconds, test specimens MAY HAVE a burn-through (A hole may be present)
5VB Surface Burn; Burning stops within 60 seconds, test specimens MAY NOT have a burn-through (no hole).
Understanding plastics and their flame retardant properties can help the plastics engineer choose the right plastic for your projects function.