What is the limit on reimbursement of indirect expenses due to attending conferences (e.g., baby sitting, winter coat, etc.)? Going to conferences induces some costs on a researcher's personal budget. In all places I know, expenses directly related to travel and accommodation are usually covered (travel, hotels, food), but there are also some indirect expenses that aren't typically covered.

I'll only give one example, that is directly applicable to me: when I'm away I have to get a baby sitter for the kids (for the days where my wife can't pick them up, say). However, I'm sure there must be other examples.

Are there institutions that cover these “hidden” (or indirect) expenses? What rules do they follow? It must be difficult to know where to put the limit… (“hey, I'm going on a conference in Sweden in December, which means I have to buy myself a new coat! can I get it reimbursed?”)
The usual solution is very simple: you will get a daily allowance ("per diem"), which is a lump sum of money that covers all small costs related to travelling.



A concrete example: a researcher at a Finnish university, travelling to a conference in Germany. You will get a daily allowance of 61 euros per day, tax free. This should cover food and all other small expenses related to travelling.

Direct costs related to travelling (conference fees, hotel, transportation, etc.) are covered based on the receipts. However, lunch &amp; dinner is not covered, as they are included in the daily allowance. Corner cases have special rules (e.g., what if lunch &amp; dinner is included in the conference fee).