halacha - What b'rachot do you say (and when) if you drink intermittently all day?

I know people who drink water, tea, or coffee intermittently all day long, not just as part of a meal. In that situation, when would you say what b'rachot? Assume you made shehakol before the first cup of coffee; does it "expire" after a certain amount of time so you'd need another for the second cup? Or does one suffice until you interrupt with a meal?

This site talks about time limits and minimum amounts for drinks that are sipped over time, like coffee, but it seems to be talking about an extended single sitting. I'm talking about someone who gets to work in the morning, grabs a cup of coffee and takes it to his desk, refills it on his way to a meeting, refills it on his way back to his desk, and so on, all day.

Answer

Monica, I believe your link is accurate when it says that a fore-blessing can potentially last all day-unless you decided mentally that you were done or showed so physically by making an after-blessing.

The page brings 2 other examples which end a fore-blessing:

Going to sleep: Even in this scenario, it is only if you lied down in bed, showing that you are done with eating/drinking. If sleep overtakes him in the middle of eating or drinking and he wakes up an hour later, this does not constitute an end to his bracha (SA OC 178:7 +MB sk-48).

Changing your "place": If one planned to enter different rooms of the same building at the time the fore-blessing was said, no further blessing is required within the building. (Rema OC 178:1) The Biur Halacha there says that the custom is to not make a blessing even without intent to change rooms. Though he defers to those who do call changing rooms without intent an interruption, if one does so, s/he does not make a new blessing -since there is a legal doubt.

(Note: There is an assumption of general behavior that defines intent (stam daas). So if people normally carry their coffee from room to room, that is the assumed intent even without specific intent. If food is normally only eaten in a cafeteria, then assumed intent may be to not eat in a different room.)