When I joined the API 682 1st Edition Taskforce in 1991, one of the fine points of writing that I had to learn was to use “shall” instead of “should” when writing standards. “Shall” just was not, and still is not, a word in my day-to-day vocabulary. My tendency was to think, say and write “(something or other) should be designed (made of, tested – whatever)” instead of “… shall be …”.
Using “shall” instead of “should” was stressed to the point that I came to believe that API did not allow the use of “should” at all. Actually, API does allow the use of “should” and explains its use in its “API Document Format and Style Manual”. Correct usage is also explained in the Foreword to API 682 4th Edition:
“As used in a standard, “shall” denotes a minimum requirement in order to conform to the specification. “
whereas
“… “should” denotes a recommendation or that which is advised but not required in order
to conform to the specification.”
API 682 4th Edition uses the word “should” a total of 183 times! “Shall” is used 822 times. When an API standard says you shall do something, it means that you are required to do so. Seems clear, doesn’t it?
As it turns out, “shall” is not a word of obligation. The Supreme Court of the United States ruled that “shall” really means “may” – quite a surprise to attorneys who were taught in law school that “shall” means “must”. In fact, “must” is the only word that imposes a legal obligation that something is mandatory. Also, “must not” are the only words that say something is prohibited.
Here are some references that say to use the word “must” instead of “shall”:
- Black’s Law Dictionary
- Federal Rules of Civil Procedure
- The Federal Register Document Drafting Handbook (Section 3)
- Federal Plain Writing Act
- The Federal Plain Language Guidelines (page 25)
- FAA Plain Language Writing Order 1000.36, (page 4)
Frankly, the above references are so long and complex that they were of little help to me but perhaps someone with legal experience can decipher them. Interestingly, many of the references themselves use “shall” a lot.
It seems that many federal documents are being revised by replacing “shall” with “must” to indicate a requirement. I wonder if API will soon be doing the same?