Technical galleries and technical channels shall be reinforced concrete and shall be designed and constructed in necessary locations within the plant by the Contractor considering the locations and requirements of the units. Their design shall be approved by the Engineer. Galleries shall be built for units where piping and cabling systems are intense and intersect each others, and technical channels shall be installed for the remaining units. Embedded inserts and plates for piping and cable tray supports shall be provided in the technical galleries. Adequate ventilation shall be ensured and permanent lighting shall be provided through the galleries. 

Technical galleries shall be rectangular sectioned underground structure and particularly shall be used for following functions. 

* Water distribution pipes (including fire water distribution) 

* Heating distribution pipes 

* Energy distribution cables 

* Phone and fire alarm cables 

* Chemical dosing pipe systems 

* Other pipe systems of process units 

Inner net height of galleries shall be taken as 2.10 m and inner width shall be taken as 1.60 m after considering functions which are mentioned above. 

The air of the technical galleries has to be H$_{2}$S and CH$_{4}$ monitored locally and warning system shall be installed. Operation status of these sensors shall also be monitored and controlled by the SCADA. 

Top of the technical channels shall be covered with concrete hinged lid with fully water tight to prevent water infiltration from surface and underground. 

Design of technical gallery and channels shall correspond with project requirements and technical specifications. A drainage system shall be constructed in galleries and channels even though they are not present in approved project of technical galleries and channels and water which may leak into galleries and channels shall be discharged to suitable location. Slope floors of the galleries towards the drainage channel shall be provided to minimize water on walking surfaces. 

Heat isolation will be built accordingly with climate conditions for all pipes and any kind of equipment which needs heat isolation and passes through technical gallery and technical canal. There will be fire detection, vavienne LED illumination, CCTV system, gas detection, warning and ventilation. 

## 8.16.5 Installation of cables 

Cables installed on trays, ladders and trunkings must be so arranged that there are no crossings or interlacing of cables. The trays, ladders and trunkings must be sized for the cables' bending radius and weight. Cables shall be secured to the tray and ladder by means of ultra-violet stabilised tie-wraps at the necessary intervals commensurate with the cable size and weight. All cable tray, ladder and trunkings routes must be complete before cables are installed. 

Cables individually run and direct mounted on walls or ceilings must only be installed after building trades and painters have finished their work. Cables may only be installed in vertical and horizontal planes and be aesthetically acceptable taking the most unobtrusive routes possible. Single hole plastic fixing cleats only shall be used. 

All cables terminating at equipment are to employ screwed cable glands only - the use of epoxy putty is expressly forbidden. 

Cable runs shall be continuous throughout. Jointing shall not be carried out in conduits or at pulling points under any circumstances. 

Cables exposed to direct sunlight shall be able to withstand exposure. 

