Again, I prefer the brevity and concision of these examples.

It was a 2hr 3min 4sec marathon. (Is this correct if we opted to abbreviate?) The Guardian and the BBC use this so I'm assuming it's okay.

They also use both versions below: 1. The marathon lasted 2hrs 3mins 4secs. 2. The marathon lasted 2hr 3min 4sec. (Which would you pick, 1 or 2?)

  • Probably the second.
    – WS2
    Commented Feb 24, 2014 at 17:09

1 Answer 1


That's maybe a bit too far down the road, but the brochure on the International System of Units (SI) states that:

Unit symbols are mathematical entities and not abbreviations. Therefore, they are not followed by a period except at the end of a sentence, and one must neither use the plural nor mix unit symbols and unit names within one expression, since names are not mathematical entities.

And further

In any one expression, only one unit is used. An exception to this rule is in expressing the values of time and of plane angles using non-SI units.

Thus, regarding the rules of SI The marathon lasted 2hr 3min 4sec. is correct.

The brochure

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