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Appendix I

An IMS Station Model is defined for SHI (Seismic, Hydroacoustic and Infrasound), RN

(Radionuclide particulate), and for both NG (Noble Gas) station technologies as defined in Figures 1-

4.

These models define three levels for each technology: Failure Causes, Station Subsystems and

Equipment Categories. Downtime analysis reporting will be mainly made on the Failure Causes and

Station Subsystems, and also on the Equipment Categories when results would be relevant.

Figure 1: IMS Station Model for SHI

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Figure 2: IMS Station Model for RN Particulate

Figure 3: IMS Station Model for SPALAX Noble Gas

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Figure 4: IMS Station Model for SAUNA Noble Gas