Distance is quite hard to judge but then your audience is people whose job/life generally depends on quantities. Technicians, Engineers and scientists are your

Distance is quite hard to judge but then your audience is people whose job/life generally depends on quantities. Technicians, Engineers and scientists are your general target and these are people who are more in tune with quantities than the general population as a whole. That said, there are three popular classes of units in use just in the "west": Metric, Imperial/American and rule of thumb. Then there are the other ones and the really odd other ones. For example a German pfund is not the same as a pound (lb) and looks plain weird in grammes. It is however, a small cauliflower with the stalk cut off (rule of thumb). A cm is roughly 2.54 times too small for normal use and a metre is too big to fit in your tool box. I'm a Brit BTW so I actually love metric unless I'm drinking, in which case I'll have a pint unless its wine (125 or 250ml). I seem to recall that Henry VIII (the one with six wives) ordered a standard King's English to be developed which is why we have the word church and not kirk or kerke or whatever etc. That was in C16th. So, your job has a long and illustrious history. It also has the same challenges. I can imagine that it would be tempting to try and end up with something like an Anglicised Esperanto but I think you should accept that your goal will never be perfect, nor ever finally achieved. It will save lives though and you must concentrate on that and not perfection. Good luck!