Benchmarking ESD best practice across industries

I work across a range of industries and topics covering ESD in electronics manufacture, electrostatic ignition hazards in industrial processes and occasionally explosives handling. I think that static control has developed further in the electronics industry than in the other areas, partly because the sensitivity of components to ESD is often much greater than the sensitivity of (for example) flammable gases or dusts to ignition by ESD. The 100pF capacitor in a 100V HBM test contains only 0.5 uJ of energy, and most of that energy is not delivered to the device under test. In contrast 20uJ is required to ignite hydrogen-air mixture (which is quite sensitive) and 200uJ to ignite most hydrocarbon-air mixtures. So, for handling modern electronic components we have to control static electricity in some ways more carefully than in industrial processes.

One similarity that runs between the 3 areas is that human body ESD (from charged personnel) is very important in manual processes. So, grounding of personnel is a key ESD prevention measure.

One big difference is in the degree of standardisation of ESD control. In the electronics industry we have the option of compliance with one of the ESD control standards such as ESD S20:20 or IEC 61340-5-1. Standards like this do not exist for static control in industrial flammable atmosphere areas. This is deliberate on the part of the experts who write standards as industrial processes can be very different and what is a high risk in one process can be acceptable in another depending on the exact circumstances. It would be very difficult to write standards that do not burdon industry with inappropriate control measures. In contrast, in explosives handling there are well defined key control measures that are enshrined in documents such as the UK Manufacturing and storage of explosives regulations. These requirements depend on the sensitivity of the explosives handled.

In the electronics industry, we have highly automated manufacture of systems in which charged device ESD is a significant source of ESD damage. This occurs when a device itself charges to a high voltage and is the source of ESD. This type of risk is absent from industrial flammable atmosphere areas and explosives handling. However isolated conductors such as metal parts can become charged and be a significant risk in all three fields.

 The basis of static control is similar in all three fields. In manual operations, the voltage built up on personnel is controlled by grounding them. In all 3 industry areas footwear and flooring are used extensively for this. Wrist straps are used especially for grounding seated personnel in the electronics industry.

 The use of insulating materials is carefully controlled in all three industry areas. In electronics this is mainly due to their ability to build up charge and give high electrostatic fields which can induce high voltages on nearby conductors. In the flammable atmosphere areas, and in explosives handling, it is also because brush discharges from insulators can ignite sensitive materials.

 In all three industry areas it is very important to avoid having isolated conductors which can charge to high voltages and provide a source of damaging or incendive ESD. So, all conductors (especially metal items) are normally grounded where possible unless risk evaluation shows this to be unnecessary.

 Modern electronics ESD standards have a requirement that the user write an ESD Control Program Plan, and ESD Training Plan and a Compliance Verification Plan documenting what the organisation is doing for ESD control. This documentation imposes a rigour on the ESD Control Program which is very beneficial. Sadly this approach is often  lacking in the other industry areas, although less so in explosives handling. 

 So in conclusion, I believe the electronics industry leads the way in ESD control compared to other industries. This is partly through necessity due to the particular sensitivity of the devices handled, and partly because the industry lends itself to standardised ESD control measures  and approaches.