Whether you decide to provide safety equipment, or it is the responsibility of your staff, you need to make sure that it is one of your top priorities and main considerations. You should have strict codes and procedures in place when it comes to safety equipment, ensuring that nobody can work on your sites unless they are properly equipped to do so.
You may decide that it is easiest for you to provide safety equipment, especially if people are employed directly by you and are not sub contractors. This means that you are responsible for all the equipment, however, so you must take ultimate responsibility in making sure it is well maintained, and making sure that each person is using appropriate safety equipment for the task they are carrying out. Much of this will be in the remit of your site supervisors and managers, who should complete regular health and safety assessments.