Hi Andrea We do actually say 一路平安 to any acquaintances that we know who is going to have a trip or journey, it is like bon voyage or safe trip. 一路 means the trip, normally should be a long road, 平安 means safe and sound. So when you are heading home from your company, people will say 路上小心, as it is considered to be a short trip.

Take the answer above. She's well answered it. Beside, I can give you more options and examples that is equivalent to English Bye/See U/Take Care. When your friend's leaving, say, going home on feet or by car, use 路上小心, which literally means take care on road. When the person is going on a trip by train, flight, ship, and such that he can not control, use 一路平安, which mean "may god bless you a safe journey". Don't use it unless your friend's going farrrrrrrrrrrrr away. In normal days, use “走好啊” = "take care bud", "不送啊" = "literally means I wont see you off (so take care of yourself)"

In my living area, we say 一路走好 to the dead, first, they will never come back, and also it doesn't matter is the journey is safe or not, but we hope they can leave in a peace way.

because die is a journey for people

some people die both we says this