Question

some types of head protection: hard hat or safety helmet offers protection against falling objects or impact. protective cap protects against small impacts, but not against falling objects. service life a hard hat has a service life of 5 years, on average. this depends on its material. the service life can also be shortened by: chemicals direct sunlight climate the user manual states the maximum service life. extra features a hard hat often offers the possibility to fit a face visor and/or ear defenders. these can protect you against noise and splashed liquids. note:never use a hard hat that has been deformed by a falling object. when should a safety hard hat no longer be used? after the expiry of its maximum service life. if the hard hat is deformed by a fallen object. if the hard hat is uncomfortable on the head.

Explanation:

The text states that a hard hat's maximum service life is stated in the user - manual and should not be used after it expires. Also, it clearly mentions not to use a hard hat that has been deformed by a falling object. Discomfort is not mentioned as a reason to stop using it.

Answer:

After the expiry of its maximum service life.
If the hard hat is deformed by a fallen object.