100. EQUIPMENT REQUIRED Each exchange should maintain sufficient switchboard capacity, a sufficient operating force or sufficient automatic equipment to handle traffic at all times with reasonable facilities, and each telephone utility shall provide and maintain adequate telephone facilities so as to have available at all times sufficient plant and equipment to supply any reasonable potential demand for service. Traffic studies shall be made and recorded during the busy hours, to the extent and frequency required to demonstrate to the Commission that sufficient equipment is in use and that an adequate operating force is provided.105. HOURS OF SERVICE Each telephone utility shall provide emergency out- vice in all exchanges operated, in which regular service is not available at certain periods during the 24 hours of the day. When service is not continuous for the full 24 hour day, proper arrangements shall be made for handling emergency calls during the off periods, by the use of alarms maintained in proper conditions and with someone conveniently available so that emergency calls will be given prompt attention.