Hi,
In my opinion, the staff must be constantly trained on compliance with the safety rules in the workplace, it may seem trivial but in any activity where we may find ourselves physically manipulating something, such as an object with a non-negligible weight, it can lead to accidents especially when the work becomes too repetitive the resulting confidence leads to underestimate the circumstances.
Having said that, again in my opinion, this is a very generic discussion because the set of rules you can meet applied in large or very large datacenters are often different from those you can find in much more modest datacenters also because they are often conceived in a "physically" different way.
Regards,
Ferdinando