What is it called when an hourly worker is paid at a different rate for doing different things?
Solution 1:
That's actually a very uncommon thing in the U.S. because of employment law. Calculating overtime in those situations is difficult and having a policy like that can put employers into bad legal situations.
To further complicate things, each state has different rules, there is no common terminology, and in fact sometimes it's addressed by case-law rather than actually being addressed by written employment law.
Terms that you might try looking up are "scaled", "blended", "differential", "weighted" associated with "pay", "payscale", "rate", or "wage".
This isn't a topic that's easily googled. You'll want to go directly to accounting or HR online communities.
Solution 2:
Your link suggests that you are interested in legalese; if that’s the case, I cannot help you much.
But since you’re asking for terms...
I presume that you are familiar with overtime. Since you mention “doing different things during their shift”, I doubt that this is what you’re looking for.
differential pay seems to be a generic / umbrella term for a pay rate other than the standard rate. I believe that it is most commonly used to refer to different rates for different shifts (e.g., night shift typically gets paid more than day shift), so, again, I believe that this isn’t what you want.
- incentive pay is usually associated with performance (i.e., results); e.g., “You’ll get an extra forty-two zorkmids in your paycheck this week if you finish this report today.” I would expect this to be offered as a lump sum rather than a higher pay rate.
- bonus pay is similar to differential pay. While “a bonus” is almost always paid as a lump sum, I wouldn’t be surprised to hear a higher rate of pay (e.g., for especially difficult, unpleasant, or even dangerous assignments) referred to as “bonus pay”. (But see also hazard pay or “hazardous duty pay”.)
And of course I’d be making an error of omission if I didn’t mention commission. :)