The request must be made in writing and the employer has a statutory duty to consider the request seriously and to refuse it only if there are clear business grounds for doing so.
Rhaid i’r cais gael ei gyflwyno’n ysgrifenedig ac mae dyletswydd statudol ar y cyflogwr i ystyried y cais o ddifrif ac i'w wrthod dim ond os bydd rhesymau busnes clir dros wneud hynny.