To control Employees Sleeping during Work, Using Mobile phones, Talking to each other, Distracting and Disturbing other colleagues?

Can you please help me with some ideas to control - Employees Sleeping during Work, Using Mobile phones, Talking to each other, Distracting and Disturbing other colleagues?

Make a disiplinary process are add those to the rules and regulations of company and communicate them
what will be the action can be taken if they doesn't follow the rules.

Can sleep during work hours be included in Standing Orders?

Yes, please. Also refer to Model Standing Orders appended to Industrial Employment (StandingOrders) Act 1946 and Amendments, thereto and you will have clear-cut Idea.
In any case, Sleeping-on-Duty is a Grave/Serious act of Misconduct not only Unworthy of Employment but fraught with Great Risks to Life & Limb of Workers, Supervisors & all others who are at Work Premises. Effectively Deal with such/ similarActs of Indisciplne by Issuing Charge-Sheet properly drafted/framed, seeking & securingWritten Reply thereto and proceed with Internal Inquiry
In the Unfortunate event of Accident-while on Duty, the Factory Inspectorate & Law & Order Authorities shall hold the Employer, theFactory Manager and the Supervisors Liable to Penal Actions
Prevention is Better than Cure Still Holds Good.
Kritarth Team,
22.3.2019

Is it only for Factories or for Office Establishments too?