Q: What is the difference between anti-static and static dissipative floors? Which floor will be better to use if I’m going to have an electronic assembly line?
A: Anti-static is not the proper term to use for ESD flooring.
Anti-Static refers to the ability to suppress charge generation or the prevention of static build up. Anti-static materials will not safely attract or decay a static charge before it randomly discharges. Anti-static material is usually indicated by an electrical resistance range, measured in ohms, of a minimum of 1E10, (10 giga ohms), to a maximum of 1E12, (1 trillion ohms).
ESD flooring systems are referred to as static conductive (more conductive) or static dissipative (not as conductive, but will dissipate charges in an orderly fashion).
Static dissipative floors: 1E06 Ω or 1 Meg Ω to 1E09 Ω. I would consider SD material to be the minimum requirement per ANSI/ESD S7.1-2005 via ANSI/ESD S20.20-2007. If you choose this flooring system, the RTG readings may be at the low end of the scale and be in the E06 to E07 range or it may be at the high end and be in the E08 range. You want to keep you flooring system clean and always below a gig ohm.
Static conductive floors: 2.5E04 Ω to 1E06 Ω. These floors are the superior choice for an assembly environment and offer the lowest charge generation and quickest charge dissipation. These floors require proper cleaning and maintenance, but will likely exceed the requirements for 20.20 throughout its lifetime.
I’d recommend a static conductive flooring system for your application. You are dealing with ESD sensitive components, raw boards, and/or sub-assemblies that have a low threshold voltage tolerance. With a static conductive flooring system and proper ESD footwear, you will have an optimal ESDS area.