is signature of employee compulsory on each and every circular sent by HR

please help me to understand if i am sharing any circular to the employee by placing it on a notice board is this ok or should i be taking signatures of all employee as this is time consuming job .
what should be the ideal way of passing the circular if employees are not using mails and also is it ok if i inform the HOD of all departments through mail and file a hard copy of that circular with me .
Thanks
Sampada

Purpose of any communication is to make the people concerned aware of the subject matter.
Placing on notice boards is good enough to inform people, provided that the company has been doing this as a rule and everyone is aware that important notices are always displayed on boards.
but I would suggest that very important and vital communications can be made available to all persons(if strength is not large) thorough the HoD of departments concerned.