Questions And Answers

Alligator Clipped to Mat Not Recommended per ESD TR20.20-2008

“The groundable end of the cord is most often equipped with a banana plug and a mating alligator clip. Any electrical connector that could be attached to ground would be acceptable as long as it was mechanically durable. The preferred grounding point for the groundable end of the cord would be a common point ground as defined in ANSI/ESD S6.1. Also see the Grounding Section of this Handbook for further information.

NOTE: Many wrist strap users clip the wrist cord to the edge of an ESD protective mat. This process is not recommended as it can increase the total system resistance to ground to over the 35-megohm limit recommended in ANSI/ESD S20.20.” [ESD Handbook ESD TR20.20-2008 section 5.3.2.2.2 Wrist Strap Ground Cord]

However, the conductive layer would give you an argument since:

“Wrist strap ground cords must be connected to a groundable point or an equipotential bonding point. Do not connect to a snap on a dissipative mat unless it is the groundable point for the mat. Do not clip a wrist strap to the edge of a dissipative mat.” [ESD Handbook ESD TR20.20-2008 section 5.3.2.7 Wrist Strap Summary]

Due to it lower retention force than installed in a banana jack, attaching a wrist strap cord to a mat with an alligator clip is not best practice.

Grounding Mechanical Requirements per ANSI/ESD S6.1

“Wires used as the conductor for electrical bonding between ESD technical elements and the common point ground or a common connection point, and from the common point ground to the ESD grounding/bonding reference point, shall be of sufficient strength not to be inadvertently broken or disconnected. The wire shall be electrically insulated and, whenever possible, mechanically supported to physical structures to limit mechanical damage.” [Grounding ANSI ESD S6.1 section 5.3.5 Mechanical Requirements]

“Firm fitting connecting devices such as metallic crimps, snaps and banana plugs shall be connected to designated ground points. Wire splices should be crimped or soldered. Use of alligator clips is not recommended.” [JESD625-A section 7.6 ESD ground connections]