What it is for
MIL-STD-1686 sets out how a contractor should run an ESD control programme for electrical and electronic parts, assemblies and equipment. It is called up in defence contracts. S20.20 covers the same ground for industry in general, and adds a minimum set of technical requirements.
B and C compared with S20.20
| Topic | MIL-STD-1686B | MIL-STD-1686C | ANSI/ESD S20.20 |
|---|---|---|---|
| Written for | Government acquisition and contractors | Government acquisition and contractors | Any organisation |
| Minimum technical requirements | No fixed minimum | No fixed minimum | Yes: grounding, personnel grounding, insulator limits, isolated conductors |
| Data deliverables | Data item descriptions required | Dropped | Documented plan and technical basis |
| Tailoring | Allowed | Expected, and documented | Plan is built around the site |
| Design hardening tests | Required (2,000 V assemblies, 4,000 V equipment) | Left to the programme | Not covered |
| Sensitivity data | Human body model classes | Human body model plus charged device and machine model tables | Human body model classes (JS-001), and a 200 V charged device figure |
Sensitivity classes (human body model)
Both MIL-STD versions sort parts by the voltage that damages them.
- S20.20 uses the finer classes from JS-001, from 0Z (below 50 V) to 3B (8,000 V and above).
- 1686C adds charged device model (C1 to C7) and machine model (M1 to M5) tables. These do not map neatly onto the human body classes.
| Class | Voltage range |
|---|---|
| Class 1 | Up to 1,999 V |
| Class 2 | 2,000 V to 3,999 V |
| Class 3 | 4,000 V to 15,999 V |
| Non-sensitive | 16,000 V and above |
Why it matters when you buy
- If your contract names MIL-STD-1686, say so when you ask for a quote. It tells us which datasheets and test evidence you need.
- Wrist straps, mats, bags and garments are normally tested to the ESD Association or IEC methods whichever standard your contract names.
- Many defence customers also ask for S20.20 certification. Confirm with your customer before you buy.
Summarised from the ESD Association comparison of MIL-STD-1686B, 1686C and ANSI/ESD S20.20-2014. Test standards named in older documents have since been revised or replaced, so check the current editions. This is not legal or contractual advice.
Keep reading
Talk to Sucatec
Questions about your area?
Ask a specialist about products, standards or supply. We reply within one business day.
- Reply within one business day
- We supply worldwide, from Singapore
- No obligation, no spam
Prefer to chat? WhatsApp +65 8839 1637 or email [email protected].