Keep milk (or milk alternative) for a day without a fridge
I would invest in a small thermos bottle, about the size of what you need for one day. They are not only designed to keep hot food hot, they can also keep cold food cold. Choose a size that will be as full as possible when you start, it will keep better.

This is what the small B&amp;B we‘re currently staying at supplies to their guests. If it’s good for an early morning tea, it’ll be good for afternoon coffee as well:



If you want to go all the way, you can pre-chill the container, then fill it with well-chilled milk from your home fridge. You could even freeze some milk as ice cubes, if you find that it doesn’t stay cold enough until the end of your work day or your last coffee break. Store the thermos away from heat sources and not in warm sunlight, of course.

Note that you also have the “two-hours in the danger zone” buffer and that “unsafe” doesn’t automatically mean “spoiled”. Especially when the milk is still quite cold and only shortly after the two-hour window the risk for a healthy adult should be small. No recommendation, just a thought.

Switching to milk alternatives won’t change anything where food safety is concerned.