Workers Suing iPhone Manufacturing Partner Over Chemical Poisoning

You would think they would have masks to prevent something like this, or it would be in their contracts for required safety equipment.

Who's contract? Apple's contract with Wintek or the employee's contract with Wintek? I would guess that Apple's contract with Wintek would include all of the required verbage stating what environmental and occupations safety standards are required. In this case, my guess is that Wintek was falling behind on schedule or they weren't meeting quality standards, so the manager switched to the n-hexane. As for the employee's having a contract, I highly doubt it. I don't think there are Unions over in China ... but I could be wrong.

If Apple did ask them to use n-hexane, they'll probably just say "We asked them to use it, but it's their responsibility to take the safety precautions."

Where you see Hell, I see a spellbinding sense of purpose. I see the value of keeping your eye on the ball. When a bride slips the ring on her finger, when a businessman lays his hands on a Rolex, when a rapper gets a shiny new tooth, this is that cost, Mr. Beck, my horror for their beauty, my Hell for their little slice of Heaven. Somebody's gotta keep his eye on the ball. That somebody is me, Mr. Beck. I am down here every day, keeping my eye on the ball. That's just a simple fact of life. And if you're bold enough to face that cold hard fact... you can make a lot of money.

Or Apple said gave a mandate like "There are streaks all over the glass. Do something about that". And that was the manufacturers cheap answer.

However, the fact that it was a manager that was fired makes me think it was a relatively low level implementation of either safety precautions or choice of cleaner that brought this about. If it really was a mandate by Apple and the company couldn't have been any safer, they would be pointing their fingers loud and clear at Apple, not firing managers.