Equating emissions to mass loading
Given the context of your question, I assume you must mean "the associated volume", not "the associated area".  

Other than that, you are exactly correct.  For example, given the following parameters:  


  aerosol emissions rate = 0.010 mg $\mathrm{hr^{-1}}$
  duration of aerosol emissions = 1 $\mathrm{hr}$
  container volume = 1 $\mathrm{m{^3}}$


Then the aerosol mass loading would be given as:  


  total aerosol mass = 0.010 mg $\mathrm{hr^{-1}}$ $\mathrm{x}$ 1
  $\mathrm{hr}$ = 0.010 mg
  
  aerosol mass loading = 0.010 mg / 1 $\mathrm{m{^3}}$ = 0.010 mg
  $\mathrm{m{^{-3}}}$  


If you really meant area and not volume, as in surface area of the aerosols, then your statement would be over-simplified and you would need to include other assumptions made concerning particle size and density etc. in order to determine whether the way your statement is correct as written.