Guide · ESD and bench safety
How to set up an ESD-safe bench
Set up a home ESD workstation the way the ESD Association describes it: a dissipative mat, a wrist strap with a resistor, and one common ground point.
Short answer
Put a static-dissipative mat on the bench, wear a wrist strap whose cord has a built-in resistor (most commonly 1 megohm), and connect both to one common ground point that ties into the outlet's equipment ground, the third wire.[1] Plug your soldering station into a grounded outlet. And take the strap off before you work near circuits of 250 V or more: the ESD Association says wrist straps must not be used there.[1]
Why bother at home
The ESD Association (ESDA) defines ESD, electrostatic discharge, as the rapid, spontaneous transfer of electrostatic charge induced by a high electrostatic field. It can destroy a component outright or leave a latent defect, and many components are susceptible to discharges below 100 V.[2]
A latent defect is the awkward one. The part may pass your checks after the repair and fail later, with nothing to point at the cause. If you handle bare boards, loose chips or memory modules, an ESD setup is simple insurance.
The parts of an ESD workstation
ESDA lists the key elements of an ESD workstation as a static-dissipative worksurface, personnel grounding (usually a wrist strap), a common point ground and signage.[1]
| Element | What it does | What to look for |
|---|---|---|
| Dissipative mat | Drains charge from whatever sits on it, in a controlled way | A stated resistance to ground in ESDA's range for worksurfaces: 1.0 x 10^6 to 1.0 x 10^9 ohms[1] |
| Wrist strap | Keeps you at ground potential while you work | A cord resistor, most commonly 1 megohm, rated at least 1/4 W with a 250 V working voltage[1] |
| Common point ground | Ties the mat, the strap and your tools to one ground | A connection to the equipment grounding conductor, the third wire, which ESDA prefers[1] |
| Grounded tools | Keeps the iron tip from carrying charge or stray voltage to the board | A three-prong plug and published tip-to-ground figures |
| Signage | Marks the protected area | Optional at a home bench |
ESDA calls its ANSI/ESD S20.20 standard the cornerstone for ESD control programs. It requires all conductors in the work area, including people, to be bonded or electrically connected and attached to a known ground or a contrived ground. The standard was last updated in 2021.[3] A home bench does not need a formal program, but the principle is the one to copy: everything at the bench sits at the same potential.
Set it up step by step
- Pick the outlet. Use one you know is properly grounded. If you are not sure the ground is connected, have an electrician check it before you rely on it.
- Fit a common point ground. Use a ground cord or ground plug made for ESD mats, connected to the outlet's equipment ground, the third wire, which is ESDA's preferred connection.[1] Do not improvise a connection to any other mains conductor.
- Lay the mat and snap its ground cord to the common point.
- Put on the wrist strap. Wear the band snug against bare skin and clip its cord, with its resistor, to the common point. Never replace the coiled cord with a plain wire.
- Ground the soldering station. Plug it into a grounded outlet. Prefer stations that publish tip-to-ground figures: Hakko and JBC state under 2 ohms of tip-to-ground resistance and under 2 mV of tip-to-ground potential for their irons.[4][5] Few AliExpress listings publish these figures, so treat a missing figure as unknown, not as a failure.
- Keep sensitive parts bagged in their antistatic packaging until you are ready to fit them.
Grounded tools and two-prong plugs
Grounding a tool is a design choice, not a given. Hakko sells its FR-301 desoldering tool in Japan with either a three-conductor grounded plug, grounded to prevent electrostatic damage to components on the board, or a two-conductor plug.[6] Do not assume a two-prong tool is ESD-safe unless its maker says so in a specification. JBC states that its CDB station meets ANSI/ESD S20.20, which is the kind of explicit claim to look for.[5]
Common mistakes
- Treating a silicone repair mat as an ESD mat. Unless its maker states a resistance to ground in the dissipative range, it is just a heat-resistant mat. Heat resistance and ESD control are different properties.
- Clipping the strap to whatever metal is nearby. Connect only to the common point ground.
- Wearing a strap near mains. ESDA says wrist straps must not be used if you will be exposed to circuits of 250 V or more.[1]
- Trusting an "ESD safe" label with no specification. Look for resistance figures or a stated standard.
Next
Questions
How do I ground an ESD mat at home?
Connect the mat's ground cord to a common point ground that ties into the outlet's equipment ground (the third wire), which the ESD Association describes as the preferred connection. Use a ground cord or plug made for ESD mats rather than an improvised wire.[1]
What resistor should an ESD wrist strap have?
The ESD Association says the cord resistor is most commonly one megohm, rated at least 1/4 watt with a 250-volt working voltage.[1]
Is a silicone soldering mat ESD-safe?
Not unless its maker states a resistance to ground in the ESD range. The ESD Association puts ESD worksurfaces at 1.0 x 10^6 to 1.0 x 10^9 ohms to ground; heat resistance is a different property.[1]
Should I wear a wrist strap when working on mains?
No. The ESD Association says wrist straps must not be used if you will be exposed to circuits of 250 volts or higher.[1]
Do I really need ESD protection for hobby repair?
If you handle bare boards and chips, it is simple insurance. The ESD Association notes that many components are susceptible to discharges below 100 V and that damage can be latent, showing up only later.[2]