All Charged Up
What does ESD stand for?
Electrostatic discharge
What does it mean if a material has a FR package?
Material has a flame retardant package and the material will be self-extinguishing to meet a certain flame performance like UL 94
What does LOI stand for?
Limiting Oxygen Index
Why would parts need ESD protection?
Charges build on unmodified plastics and can discharge onto other parts or people
What fiber options can I add to increase conductivity of a plastic?
Carbon fiber or stainless steel commonly
Explain LOI
The minimum concentration of oxygen that will support flaming combustion
What application space tends to need the most protection from a discharge event?
Electronics/Semicon devices/circuit boards
What non-fiber option can be added to a plastic material to increase conductivity?
Anti-stat additive or lots of carbon black
What are some inherently self-extinguishing materials?
PEEK, PPS, PEI, PPSU, PESU
Resistivity (surface or volume) is the means for measuring conductivity of the material or how readily it will move a charge - a low resistivity means it is more conductive like metal, a high value would be insulative and more like plastic
What is a large reason FR packaging containing materials cannot be used in mass transit applications with FST requirements?
The FR packages tend to smoke when burning and results in a smoke density failure (FST)
What is the difference between V-0 and V-2?
V-0 is a 10 second extinguishing time vs 30 and cannot have a flame drip/cotton igniting like V-2
What are the three ESD categories and they resistivity ranges?
Anti-stat: 10^9 to 10^12
Static dissipative: 10^6 to 10^9
Conductive: ≤ 10^6
What does non-hal mean for a FR package? What are some of the hals?
Means it does not contain a halogen in the package. Halogens would be elements like chlorine or bromine
What is 5V testing? What is the difference between the two results? When is one needed?
5V testing is a plaque tested with flame directly in the center of the plaque. 5VA allows no burn through though 5VB does. 5VA is a min requirement for a permanent mount unattended piece of equipment