I recently submitted a paper that includes formulas related to building physics, such as

Q = K (t_b - t)

where Q is the daily heating load, K is the building's heat loss coefficient, and so on. All the quantities should be familiar to the reader.

A reviewer asks that I provide units for the quantities in this (and other) formulas. But this formula will remain true no matter which system of units I use.

Should formulas include units? If not, how can I tactfully rebut the reviewer's request?

  • You're right, they shouldn't. You can referer them to quantity calculus. I can give you a few references, but now I don't have the time to write a proper answer. Jun 2, 2017 at 17:12
  • 2
    @MassimoOrtolano is talking about Buckingham's \pi calculus. The unit system may need to be specified generally, because physical equations have different constants depending on the unit system (e.g. Maxwell's equation have different factors in SI and Gaussian systems), or cosmological equations set c=h/2\pi=1. So, it might be good practice to mention the unit system used for the particular set of equations. However, if you use SI units overall (or some other common unit system in your branch of engineering), it should not cost a lot to add a sentence. Jun 2, 2017 at 17:19

1 Answer 1


There are two possible issues. If the reviewer simply thinks that units should be provided for stylistic purposes, then you should look through a couple of past articles and see if they provide units. If they do, follow the model. If they don't you can respond with it appears that units are not typically included in << The Journal Name >>, but if there has been a change in style the units can be included.

The bigger issue is if the reviewer is confused (or believes the reader will be confused) and that providing units will clarify the confusion. If this is the case, then not providing units is a big deal. In this case I would provide units in terms of fundamental dimensions (e.g., length instead of meter and time instead of second).

  • 1
    I agree and disagree with the second paragraph. I agree - if reader will be confused, providing units is big deal. I disagree in providing them in fundamental dimensions. (At least in this case- this equation is in applied heat transfer and thus I assume 1) a lot of the other calculations are heat-transfer related; 2) somewhere there are some numerical results). Heat transfer coefficient K - which would normally be Watts/m^2 degK) has some weird things going on in some engineering subfields. I assume the point the referee is trying to make is to make sure that everything is unambiguous.
    – Carol
    Jun 3, 2017 at 17:27

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .