A smock is a grounded conductor, not a uniform
What an ESD garment actually does
An ESD smock is made with a conductive fibre woven into the fabric, so the garment forms a continuous path from the body to the ground reference rather than letting charge build on synthetic clothing underneath.
That path only works if the garment is worn closed and grounded. A smock left open, or worn over a nylon jacket, is a partial solution at best.
Sleeve length is the specification
Most garment failures in practice are fit failures. A sleeve that stops above the wrist leaves the forearm exposed, and the wrist strap covers only the wrist, so the gap between cuff and strap is where charge accumulates.
The usual requirement is a cuff that reaches the wrist bone with a snug elastic or conductive knit cuff, so that the fabric and the strap overlap. Ordering by chest size alone is how sites end up with sleeves that are too short on taller operators.
Fabric, laundering and lifetime
Conductive garments lose performance with washing cycles and with fabric softener, which coats the fibres. Laundry should follow the garment supplier instruction, avoid softener, and be recorded so that garments can be retired on a cycle count rather than on appearance.
Grounding is tested, not assumed: a sleeve-to-sleeve or sleeve-to-ground resistance check on a sample of garments at a defined interval is the only way to know the fleet is still working.
FAQ
Do ESD smocks replace wrist straps?
No. A smock controls charge on clothing and the body; a wrist strap provides a direct, low-resistance path from the operator. Most plans require the strap for seated work and treat the smock as complementary.
How long does an ESD garment last?
It depends on fabric, wash cycles and care. Retire garments on a recorded wash count or on failing a resistance check, not on visible wear.
Can ESD garments be washed at home?
Not normally. Home detergents and softeners leave residue on the conductive fibres. Use the supplier approved laundry process and record the cycles.
What matters most when ordering?
Fit at the cuff. Specify sleeve length against the wearer wrist position and confirm the cuff design, then check chest size.
All figures above refer to standard product data sheets; final confirmation is subject to written quotation.