As someone that has worked at Workplace Safety organization. [...] Safety design, ratings and certifications are the only thing that matters. Accuracy and resolution important? No. Great display and black light important? No. Cheap price with lots of functionality? No.
Well, that's a perspective. For a commercial electrician who rarely sees anything under 100 Vac or circuits smaller than 15 A, it's applicable.
For someone that works on digital logic where 5Vdc is considered a high voltage and sub-watt power is the norm, it is not applicable, and accuracy and resolution are much more important than safety. I'm not sure what an unsafe multimeter would look like at 3.3V; maybe one with sharp edges?
You have to assume that any existing DMM will someday be hooked up to mains power at some point of time.
Being safety focused is a laudable goal and I am not trying to discourage an active consideration of safety where electricity is concerned, but I think a lot of people go too far and make residential CAT II 120-240Vac out to be some sort of boogeyman. I think it is great that modern multimeters have all this built in protection, but in a non-commercial hobbyist setting, even a somewhat inexpensive multimeter is most likely the safest device in the room compared to all the cheap USB chargers, questionably "double insulated" DVD players, toaster ovens with "value engineered" cords, etc. Most consumer devices have little to no concept of input protection beyond a (usually non-HRC, in North America) fuse, and from design to assembly a lot of the decisions made are not exactly safety centric. According to the multimeter-universe rules people should be dying left and right.
Treated respectfully, residential mains isn't too bad; certainly not the monster people make it out to be. With AFCIs and "tamper resistant" outlets now being mandated in code, you even have to go through some effort to scorch things.
On the other hand, commercial electric work with CAT III sources and up is a completely different story. 480Vac arc flash is an incredible force, and I've seen the results in person. Not something to play around with. ElectroBOOM wouldn't be able to get away with what he does at 480V; if someone did that sort of thing at 480V or above I think about the best they could hope for would be to lose an arm. But is that really what we are talking about here? I can't see an entry level hobbyist buying their first multimeter and finding some 3 phase bus bar to go probe or trying to grappling hook an overhead power line.
I think we're at the level of safety now, more or less across the board, where danger comes from bad decision making rather than unexpected equipment failures. That's the point at which I would call equipment "safe," for my own purposes. Companies can and do make multimeters that protect people from bad decision making (e.g. sweeping across the dial while still connected), which I think is an amazing feat of design. But the only way that would make
people safe is if all they ever did was probe things with a multimeter. I have to expect that people interested in electronics (or working in an electrical profession) do more than just probe things all day. You aren't going to make a wire that protects itself from becoming a short, or a capacitor that stops someone from soldering it in backwards. If people can't be trusted not to try and measure across two 480Vac bus bars on the 10A range, even if it's just because they're tired and having a bad day, I think something is going to get them sooner or later even if it isn't their meter.
In the case of 480Vac arc flash I saw, someone just wired a short into a piece of switchgear because they misunderstood the diagram. It blew the 5' front panel off of the switch, and if they had been standing a foot closer it would have taken them with it. They had a perfectly safe modern multimeter, but neither the terminals nor the wire said "sorry Dave, I can't do that" when they were being torqued down.
In my opinion, equipment free from unexpected failures and a working mind are what are necessary for safety, and I think many analog meters are capable of serving in that role. If I were doing commercial electric work professionally, of course I would use something explicitly CAT rated for the purpose from a reputable manufacturer. But low voltage hobbyists are in the position of reasonably being able to use whatever they want or can afford.
Oddly enough I do have a safety rated analog multimeter, the
Simpson 260-9SP, CAT III 600V rated. Orange meter in the orange case below:
I would comfortably use anything in that photo to measure up to 240Vac mains, including the small Triplett pocket meter, although it's probably not one I would recommend to someone else for the purpose. I would only use the 87V or the orange Simpson for CAT III work above 240V. The yellow banana in front of the meters is a Fluke C9970 (formerly known as the Western Electric 188A) for checking whether something is live (up to 20kVAC) which is something I prefer not to use a meter for if I can avoid it.