SUB STATION - There are two sub stations, one in the Preveza Service Building and the other one in the Aktio Service Building, which are sharing the tunnel’s electrical loads.Every sub station includes  two (2) three-phase distribution transformers (T/F) using as cooling medium oil, Nominal power 400KVA and transformation rate 20/_0,4 KV. There are two (2) Diesel Generator Sets of nominal power 400KVA each, (one is reserve of the other) providing a back up power in a case of a power cut because of a failure on PPC electrical network. There are two (2) UPS of nominal power 60KVA each for the resumption of the critical loads. The total autonomy time provided by the UPS system in the max loads is about 30 minutes. Mid Voltage and Low Voltage Area

LIGHTING - The lighting of the tunnel is automatically adjusted in relation to the day light through photo cameras and a system of inverted voltage transformers which are fluctuating the brightness intensity of the lights in threshold and transient light zones of the tunnel, succeeding the proper lighting level.

Threshold zone is the first section of the tunnel in which lighting has to be in such level that the driver can adjust easily from the day light to the tunnel lighting. That means that the lighting level in this section has to be high enough.

Transient Zone is the section that follows the threshold zone in which the lighting level is gradually reduced, in order to give to the driver the time to adjust to the tunnel low lighting level (internal zone). Louvers have been constructed in tunnel’s entrances in order to reduce the daylight. The length of the louvers in each side is 75m, and is part of the threshold zone. Artificial lighting has been installed in the rest of the threshold zone in order to succeed the demanded brightness. We note that through the SCADA system we have the ability to operate manually the light levels from the Control Room, if it is necessary.

Louvers have been constructed in tunnel’s entrances in order to reduce the daylight. The length of the louvers in each side is 75m, and is part of the threshold zone. Artificial lighting has been installed in the rest of the threshold zone in order to succeed the demanded brightness. We note that through the SCADA system we have the ability to operate manually the light levels from the Control Room, if it is necessary.

VENTILATION - There are 14 pairs of fans every 120m, placed on the tunnel’s sidewalls. The values of CO / VIS sensors determine the automatic operation of the fans. When these values reach to specific limits (which are predetermined) 4,8 or12 pair of fans are getting started. We can be informed for CO/VIS measurements, from the SCADA system. Tunnel Ventilation operates in relation to the direction and the velocity of the wind outside and inside the tunnel. We note that through SCADA system we have the ability to operate fans manually from the Control Room, if it is necessary.

PUMP STATIONS - There are two (2) drainage pump stations in both the Aktio and Preveza entrances and another one in the tunnel deepest (lower) section.

FIREFIGHTING PUMP STATION - The fire fighting system is composed of two (2) electrical pumps and a jokey for the counterbalance of the pressure falling. The water is pumped out from a tank (120m³) and through a PE pipe, 3^rd generation Φ200, PN16 supplying the tunnel’s firefighting main.The firefighting stations (F.S) are equipped with a fire hose, a foam generator and a portable fire extinguisher and are located every 50m on the tunnel’s sidewalls. There are phones for the internal communication in every F.S. and First Aid Station (F.A). The Emergency phones, are supported by 3 communication channels, Fire brigade, Police, Ambulance, and are installed every 100m. The Lighting signals are installed on the top of the F.S. and F.A boxes, informing the drivers of the installing equipment

FIRE DETECTION SYSTEM - There are two fire detection systems, one for the tunnel and a separate one for the Service Buildings. Tunnels’ fire detection. A linear fire detection cable on the roof of the tunnel, divided in four zones, detects the temperature increase transmitting a fire alarm signal to the Control Room. The tunnel (closed section- sub sea section ≈1600m), is divided into 4 fire detection zones, every 400m, A-B-C-D, from Aktio to Preveza side. In a case of an alarm, traffic lights in Preveza and Aktio automatically turn red and if funs are in operation, they stop automatically. Buildings Fire detection is operating through smoke, temperature differential and visual sensors. The alarm (signal) is displayed on a different firefighting board in the Control Room.

RADIO TRANSMITTAL SYSTEM - The Radio transmittal system is composed of, a radiating cable 7/8″ on the roof of the tunnel, which is used as an antenna and allows the communication in 3 channels (Police, Fire brigade, Maintenance team). The Receiving and Transmitting (R/T) antennas through mobile units are installed on the roof of Preveza Service Building and the electronic equipment in the Control Room, which includes the main system and the R/T channels

EARTHQUAKE CONTROL SYSTEM - The earthquake control system detects and reports any earthquake that occurs near the tunnels’ area, and is composed of the Measurement Sensors, in a case of movement of the joints (between the tunnels’ sections). The Force Balance Accelerometer. The Main monitoring system, which is wired with the installed equipment (this system collects all the measurements from the sensors and at the same time checks the equipments operation). The Software used for the measurements as well as for the production of alarm signals in a case of exceeding the predetermined limit values and finally the Connection Cables.

MAIN CONTROL - The signal cables are wired to 16 P.L.C.’s which through fiber optics transfer the data to a Main Control Unit, which is installed in the PLC Room in Preveza Service Building and from there through profibus to the SCADA system and the Mimic Panel