A network of 15 Medipix2-based detectors (ATLAS-MPX devices) has been installed at various positions in the ATLAS detector and surrounding cavern. The main aim of the network is to perform real-time measurement of spectral characteristics and composition of the different radiation types in the experiment with a focus on slow and fast neutrons. However, the versatility of the ATLAS-MPX devices allows its use for other specialized tasks including the particle punch-through (or leakage) important for calorimetry and transverse energy measurements. Measurement of the background muon distributions is also possible and some preliminary data are presented. In addition, a study leading to an estimate of the radiation induced Single Event Effect (SEE) probability for a ATLAS-MPX device is presented.