To protect the workers, the 'book' need not conform to anything elsewhere.
All that is required is that - whatever 'it' is - it's 'in the book' as written by the employer for the employee to carry out as instructed.
Then, as long as the employee carries out the written instructions of the employer, as far as I understand it, they are protected.
Vicarious Liability - a Legal delegation of Responsibility.
A 'Legal Eagle' may be able to elaborate if required.
