Max: I should go to bed. I have to wake wake up early to get to the airport by eight tomorrow morning.
Naomi: Don't worry, Max. I'll drive you.
Naomi: Don't listen to her, Max. I am a safety driver.
Max: Okay...but I hope you are a safe driver.
Lots of Japanese people say they're safety drivers. I am sure they are but actually, they mean they are safe drivers. Drivers is a noun so you need an adjective -- safe.
When can you use safety? Well, this familiar sign uses "safety":
Can you translate it? Right, it says "Safety first."
Of course, I always think in terms of movies. Here is the scariest use of the word "safe" you will ever hear. "Is it safe?" You tell me.