If you send a text at work and don't get a response how long do you wait before trying again?

Sending text messages at my work is forbidden, so I wouldn't even do that, because that's (usually) private related than work related. People can be a the toilet, have a meeting, be too busy with an assignment,.. What I do when I want to contact a co-worker, I first call them, and if they don't pick up (because of the named up examples) I send an email and just wait until I get a reply, and continue with my work. And only if I haven't heard back from this person the next three days, I'll contact them again after I asked around if that specific person is present at work at all or absent. Have respect for other people at work, always show patience and never impose yourself to anyone.