Do you break the glass in case of emergency or in the event of emergency? The phrases in case of and in the event of are both prepositions. The first one means if it should occur. The second means if or when something happens.
A preposition is a word or phrase that shows a relationship between two elements in a clause. Some common prepositions are on, after, before, and if. For example, in the sentence “The man sat on the chair,” the word on tells you the spatial relationship between the man and the chair.
Difference in Meaning
In most cases, you can use in case of and in the event of interchangeably. Grammatically, either really correct. For instance, it’s acceptable to say “I brought my umbrella in case of sudden rain.” It’s equally acceptable to say “I brought my umbrella to be prepared in the event of rain.”
There’s a slight difference how these two terms are usually used. Many times, in case of implies that you’re taking some action as a precaution against an unexpected event. For example, you might bring seasickness pills on a cruise in case of stormy seas. You don’t necessarily expect stormy seas to happen for certain, but you’re prepared if they do.
On the other hand, in the event of usually refers to what one should do if something happens unexpectedly. For instance, “In the event of an earthquake, stand in a doorway away from the windows.” This means that if or when an earthquake happens, this is what you’re supposed to do.
The term in case is often used without the preposition of to mean if. So if you were to say “Here’s my phone number in case we get separated,” you’d mean the other person should use it if the two of you get separated.
People also use just in case in this way. For instance, a mother might warn her child, “Bring an extra pair of socks, just in case your feet get wet.” Just in case can also mean in the event something happens. For instance, “He took along his extra socks, just in case.”
In the same way, people sometimes use the phrase in the event that instead of in the event of. For example, one might say “Call me in the event that you need a ride.” In this case, you could just as easily say “Call me if you need a ride.”
The phrases in case of and in the event of have very similar meanings. People often use them interchangeably, but they do have some slight differences. In case of usually implies that a person is preparing for an unexpected event. In the event of refers to actions one should take if an unexpected event occurs.