It has been over six years since IEEE 1584 introduced electrode configurations in the 2018 edition.
This survey question is about electrode configurations. Specifically, if you conduct arc flash studies, review them or contract them out, what is the most common electrode configuration that is used? Each configuration affects both the incident energy and the arcing current.

What is the most common electrode configuration that you use or see?

VCB - vertical conductors/electrodes inside a metal box/enclosure
VCBB - vertical conductors/electrodes terminated in an insulating barrier inside a metal box/
enclosure -
HCB - horizontal conductors/electrodes inside a metal box/enclosure
VOA - vertical conductors/electrodes in open air
HOA - horizontal conductors/electrodes inside a metal box/enclosure

SKM defaults to VCB for most busses. I go back through my model and change anything with a main breaker, a molded case switch or disconnect switch to VCBB and anything else that is not "standard". I then check the box in SKM to also run VCB and HCB for all VCBB buse and report worst case.

It can be challenging to appreciate the need to calculate and report the worst-case configuration scenario for at least two reasons:

Accuracy of Information – You either know the system configuration or you don’t. In the field, we’ve seen AF study companies that simply ask for a single-line diagram and then send back a report and labels, often without verifying accuracy or settings. When we suspect this, we note it in our assessments and recognize which companies to be cautious of when reviewing labels. Similarly, if every label on a commercial site relies solely on the PPE category method ("table method") without an accompanying report, we assume the fault current may not have been correctly applied. In all of these cases, we assume due diligence was lacking and take precautions accordingly.

Overestimation Concerns – Automatically assuming the worst-case scenario can lead to unnecessary costs and operational burdens. Employers may end up purchasing PPE with excessive ratings or implementing restrictive safety measures beyond what’s actually needed. Since arc flash calculations, when preformed accurately, already tend to be conservative. Additionally, most employers won’t permit workers to wear a 40-cal suit if the incident energy (IE) is calculated at 39 or 40 cal/cm²—they typically require "headroom" or some sort of margin. Therefore, adding additional buffers in the report is often less important than ensuring accuracy.

That said, if a facility has a history of poor equipment maintenance, I would lean toward selecting the more conservative IE result through rounding up or "fishing for the bottom" but not by changing the electrode configuration. I also note in the report that it relies the equipment owners proper maintenance per the standard, while recommending our EPM program.