Posted By lewes A lot of it depends on the work enviornment and the number of people. Have a look at http://www.hse.gov.uk/pubns/indg214.pdf it should answer your question.

Posted By Brian Hagyard Jon. You are quite right that the requirement for first-aid personnel is all down to risk assessment. Remember L74 (which I think is the document you are quoting from) is an ACOP and Guidance document, and unless the document has been reprinted since 1997 (I am unable to find a second addition on HSE books) I understand it to say the following. The ACOP part (paragraph) 44 states that where 50 or more people are employed at least one person should be available to provide first-aid. The Guidance is for 50 to 100 employees in office type locations you need one first aider and an additional first aider for every additional 100 persons employed. As I read the document and from your posting you currently comply with the ACOP and could comply with the Guidance with 1 additional person. As you obviously know the ACOP has special legal status and Guidance is just that guidance. If you think you can justify 1 first-aider to 150 staff then fine, I would personally wonder what happens when that person is on holiday/sick or away from the office for any other reason?. Also how easy are they to contact and how quickly would they be able to administer help? Again these are all issues you should take into account of in your risk assessment, which without knowing all the details of your situation it is difficult to comment on, but I would echo the words of caution already offered. Hope that helps. Brian.