Mandatory Safety Signs from BiGDUG. This safety sign should be used to instruct and advise individuals of actions that must be carried out. This cost effective and durable Mandatory sign is available in self-adhesive vinyl and 1mm rigid plastic. All BiGDUG safety signs are fully compliant with current UK & European health and safety sign legislation. With our competition-beating prices unbeatable customer care and fast delivery on all orders; why would you want to buy your safety signs and warning signs from anyone else!