There is a great deal of health and safety legislation in the U.K and much of it is not relevant to the typical office based business.
However, it is often hard for the employer to decide what does apply to their business. You are likely to be a low risk environment but you still want your employees to be safe.
If the worst happens and there is an accident resulting in injury (or even death) to any of your staff or visitors, you want to be able to show that you have complied with your legal responsibilities but you don’t want to spend money on unnecessary documentation and solutions that aren’t relevant to you.