## ANNEX C. Special Design requirements 

a) The Watertight Data Cable has to include: 

a. Two separate cables, one inside the torus terminated in a socket on the outside of the torus, and a second cable (15m) that connects from the socket to the control box (terminating in an RS485 connector. 

b. The socket shall be waterproof (leak tight). 

c. A protective EPDM sleeve shall cover the cable. It shall not be required that the cable connectors be removed in order to install the sleeve. 

b) Water-tight testing capability: 

A method for routine testing of the watertight seals (e.g. using a helium leak test) shall be provided. The valve for introducing gas to the torus must be protected from breakage during shipment and use. 

c) External Markings: 

The torus shall be marked externally to indicate the 0-degree position of detector head 1. The marking must be easily visible from the surface of a spent fuel pond and shall consist of a line that is parallel to and above the front of the collimator of head 1. 

d) Data-Collection Software: 

The system shall be fully compatible with the IAEA PGET software, according to the IAEA document SG-UR-14008 -- Passive Gamma Emission Tomography (PGET) Software -- v3 (2016-08-18) , which can be provided in advance to the awarded contractor. 

e) Gamma-ray Collimator Redesign: 

Improvements to the design of the collimator, compared to the detailed specifications, are welcome with the following constraints: 

a. The collimator shall accommodate 91 detectors (7 back-end boards). 

b. The collimator shall enable easier placement of detector components (back-end board modules) inside; 

c. Cable penetrations shall be redesigned to allow easier installation; 

d. The horizontal pitch of the collimator openings (4.0mm +/- 0.01mm) and width (1.5mm +/- 0.01mm) shall strictly remain the same. 

