Well... a few standards (probably the less important ones, but probably the more esoteric and numerous ones too) will have come directly from whole companies, sort of as a means of specifying their product. And in turn, limiting their competitors.
(One of the prime economic goals of regulation is to insert barriers to entry: if it's more expensive for you, it's more expensive for your competitor; but if you get to set the rules, you have a leg up on them. And barriers in terms of direct costs, capital, and development time, limit the rise of new competitors, which is better for both you and your competitors.)
For example, the PDF standard obviously was invented by Adobe, and now it's ISO. (Nevermind that Adobe's relentlessly buggy design made it into the standard, so that it is not possible to implement a truly standards-compliant viewer, let alone one which is secure in any meaningful way.)
I think I heard that some of CISPR came straight out of Philips, but I don't know to what extent, nor how true, that is.
As for practicalities:
EMC itself is based on radiators and susceptibility.
Radiators need to be below a certain level, with unintended radiators being low across the range, and intended radiators being allowed a certain amount more, only at limited frequency ranges.
Meanwhile, susceptibility needs to be tolerant up to some level, which is above the level of most intentional radiators, and many decades above the level of unintentional radiators.
This ensures that:
- Unintentional radiators do not cause malfunction of other devices
- Nor cause impaired reception for radio services and communication devices
- Intentional radiators do not [usually] cause malfunction of other devices
- Devices are capable of failing gracefully under disruptive conditions from strong radiators and environmental events (such as ESD and surge).
The customary levels are (ballpark) < 1mV (e.g. conducted via AC line) for an unintentional radiator, versus 3V (conducted, or 3V/m radiated) tolerance for susceptibility.
Intentional radiators are usually under a watt (e.g., free/ISM band devices like CB, FRS and Wifi), so not too much induced voltage at a modest distance. And of course, registered radiators going up to whatever they're licensed for, but there are fewer of those, and only licensed for allowed locations (fixed or mobile), so if you're in the area of one and your otherwise-compliant devices start to malfunction, well that's just kind of what happens.
Now, the matter of testing, at a nationally accredited lab, performing tests in line with every possible country's versions of these rules, is rather expensive. But that's not an anticompetitive measure undertaken by greedy lobbyists -- it's an anticompetitive measure which arose as an emergent property of individual greed. Everyone wants to sue for the littlest thing, so if you have the fancy notarized papers saying you did your due diligence, it ultimately saves more money in the long run.
TLDR: Afraid I don't have any history, sorry.
Tim
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