Posted By Chris Knagg It is always good practice to refresh the training given to staff on any emergency procedure or formal training. As a business you can decide the frequency of that refresher training. As a guide and in general most vocational training given is refreshed every three years however if the spillage procedure is safety critical you may wish to shorten that period. Its down to risk assessment, how often are there spills, what is the substance that is spilt, what is the potential for damage, loss and injury etc and who might be affected. And finally does the procedure work and do your staff follow procedure when they have been trained, how long before they forget to do what they have been trained to do?