"Not Less Than"

[bwat]

Anybody have a good answer for why the NEC uses the wording "shall be not less than"? It's similar to a double negative for me and I always mentally translate it to "shall be at least". In the scenario of "Not Less Than", equal to is permissible, and so is greater than. So "at least" would be a much more common way to say it, especially if following a "shall be".

The phrase "Conductors shall be sized to carry not less than..." would be a lot easier to read and grasp upon first read if it said "Conductors shall be sized to carry at least..."

It drives me nuts a little bit, and perhaps it wouldn't if I understand why they are doing it that way.

 

[Joe.B]

Complete guess, but I think "at least" doesn't translate as well as "not less than". The code is used in so many places and needs to be interpreted by a variety of users and jurisdictions, I think they are trying to be as clear as possible. Language is a funny thing, and English in particular can be tricky. "English" is spoken in many places but I swear sometimes it sounds like a foreign language.

 

[bwat]

Complete guess, but I think "at least" doesn't translate as well as "not less than". The code is used in so many places and needs to be interpreted by a variety of users and jurisdictions, I think they are trying to be as clear as possible. Language is a funny thing, and English in particular can be tricky. "English" is spoken in many places but I swear sometimes it sounds like a foreign language.

Interesting guess. Although if you happen to have PDF version of the NEC and do a search for "at least", it shows up all of over the place in the same type of usage that "not less than" could have also been used.

110.9 Interrupting Rating. Equipment intended to interrupt
current at fault levels shall have an interrupting rating at nominal
circuit voltage at least equal to the current that is available
at the line terminals of the equipment.

 

[Dennis Alwon]

I have heard similar complants about the wording in some section on that issue

 

[jim dungar]

Some code wording is over 100 years old. There have definitely been changes in common usage during that time period

 

[zbang]

I'll go down the route that "at least" doesn't always mean "equal to or greater" ("At least, we didn't have to go to the hospital.") and that "not less than" makes the reader immediately think of a quantity or measurement. Also that N-L-T is slighter shorter than "equal to or greater".

In the 110.9 quote, "at least" is used with "equal" to clarify the intent. So we could have-
...at least the current...available...
...at least equal to the current...available...
...not less than the current...available...
I find the first a little vague. Might be understandable, but clear language makes for a better code and we spend a lot of time discussing things that just aren't clear.

 

[don_resqcapt19]

The NEC Style Manual specifies the use of many terms. This information is from the 2020 edition of the style manual which is being used for the 2023 code.

3.2.2 Expressing Maximum and Minimum Limits.
Maximum and minimum limits shall be expressed with the types of wording shown in the following examples:
Examples:
Shall not exceed 300 volts to ground . . .
Shall have a clearance of not less than 5 cm (2 in). . .
Shall be supported at intervals not exceeding 1.5 m (5 ft.). . .

3.2.4 Standard Terms.
Standard terms have been established through accepted use or by definition and are to be used in preference to similar terms that do not have such recognition. Annex A provides guidance for syntax, spelling, punctuation, and usage of many standard technical terms

This is from the Annex A list of standard terms.

at least (avoid; use not less than to indicate minimum

 

[synchro]

"At least" seems to have the connotation that more is better and additional margin beyond the given value may be appropriate. In contrast, "not less than" makes clear what is not allowed and therefore can be identified as a violation. If otherwise, it will be allowable.

I'm in agreement that the wording "at least" is much easier to understand than "not less than", especially if it's in a long sentence. But I think "not less than" is more definitive wording for code enforcement purposes and less subject to debate.

 

[LarryFine]

It bothers me to hear phrases like "ten times bigger" or "ten times smaller."

What is "one time bigger" or "one time smaller"?

 

[acin]

430 .32 A1 Rated at no more A2 Shall not exceed

 

[wwhitney]

It bothers me to hear phrases like "ten times bigger" or "ten times smaller."

Those are perfectly good phrases, just in reference to a multiplicative scale, rather than an additive scale. Same as "a factor of 10 larger" or a "a factor of 10 smaller."

What is "one time bigger" or "one time smaller"?

Equality. The same as "zero more" or "zero less."

Cheers, Wayne

 

[LarryFine]

Those are perfectly good phrases, just in reference to a multiplicative scale, rather than an additive scale. Same as "a factor of 10 larger" or a "a factor of 10 smaller."

So, if something is five times bigger, what does that mean? Does one time bigger mean twice as big? What about two times bigger? Does that mean doubled twice?

Equality. The same as "zero more" or "zero less."

Huh?

 

[wwhitney]

So, if something is five times bigger, what does that mean? Does one time bigger mean twice as big? What about two times bigger? Does that mean doubled twice?

X is 5 times bigger than Y means X = 5 * Y.

X is 5 more than Y means X = Y + 5.

So X is 1 times bigger than Y means X = Y. Just like saying X is 0 more than Y.

Edit: to mix it up, X is 100% more than Y means X = Y + 100% * Y = 2 * Y. As opposed to saying that X is larger than Y by a factor of 200%, that would mean that X = 200% * Y = 2 * Y.

Cheers, Wayne

 

[bwat]

Wow. Fantastic information. Thank you. Glad to see it is rather intentional. It might bother me less now.

The NEC Style Manual specifies the use of many terms. This information is from the 2020 edition of the style manual which is being used for the 2023 code.



This is from the Annex A list of standard terms.

Seems like they agree with you based on the style manual that Don posted. Thanks.

"At least" seems to have the connotation that more is better and additional margin beyond the given value may be appropriate. In contrast, "not less than" makes clear what is not allowed and therefore can be identified as a violation. If otherwise, it will be allowable.

I'm in agreement that the wording "at least" is much easier to understand than "not less than", especially if it's in a long sentence. But I think "not less than" is more definitive wording for code enforcement purposes and less subject to debate.

 

[jimport]

Reminds me of the requirements for correct colors of conductors. Instead of saying larger than 6 it would make more sense to me to say 4 and larger are allowed to be reidentified.