Realize what causes hearing loss and use common sense. If you're exposed to loud sounds, use ear protection.
They're fine to use. Just be sensible about the volume and amount of time you listen. If the person next to you can hear your music, it's too loud.
We're moving sound closer and closer. It's really increasing pressure on the ear.
If the volume is up to over 100 decibels, even one and a half or two hours of use can cause damage.