I understand there is a lot of misuse in terminology, and we have become accustomed to making assumptions and reading between the lines. But here is a simple scenario to illustrate the importance of being accurate:
We both receive a set of drawings to bid on, and the load list has a bunch of loads on it that requires say 20 - xfmrs to be purchased that are 480-120/240V. So, we both send it to the estimators to bid it, you say to the estimator, oh BTW I think those transformers are 3-phase; I on the other hand, bid it as written. Your price is too high and I am awarded the job.
The day after the award, I send in an RFI and ask for confirmation that the loads are single phase, and the response comes back saying they are all three phase. So, I issue a change order to the Owner and he says no way am I paying for that. My response is that according to ANSI/IEEE C84.1 the information provided clearly says single phase (480- 120/240V) but the RFI confirms three phase is required. I get my change order and ironically my bid with CO is actually higher than your original price. But I got the work and made more money. Why? Because I did not read between the lines, or assume I new what they were talking about. I simply used the industry recognized standards to go by to win my case.
If it's 220V it's 220V, not 220 or 221 whatever it takes!
Cheers!