3.2　Datum Line and Datum Mark for Installation of Equipment

3.2.1　Before the installation of equipment，the datum line and datum mark of installation shall be set，which shall be in compliance with the following requirements:

1　Draw the arrangement diagrams of datum line and datum mark in accordance with design documents；

2　Set central target and datum mark in accordance with basic handover material and the arrangement diagrams of datum line and datum mark；

3　Survey datum line and datum mark in accordance with site surveying control network；

4　Main body equipment shall be embedded with the central target and the perpetual datum mark；

5　After surveying，the measuring result report shall be submitted.

3.2.2　After the equipment installation Work is finished，the perpetual central target，the perpetual datum mark and arrangement diagrams thereof shall be handed over construction units.