[en] Additional criticality safety analysis of a pool type storage for TRIGA spent fuel at Jozef Stefan Institute in Ljubljana, Slovenia, is presented. Previous results have shown that subcriticality is not guaranteed for some postulated accidents (earthquake with subsequent fuel rack disintegration resulting in contact fuel pitch) under assumption that the fuel rack is loaded with fresh 12 wt% enriched standard fuel. To mitigate this deficiency, a study was made about replacing a certain number of fuel elements in the rack with absorber rods. For this purpose Monte Carlo computer code MCNP4A with ENDF-B/V library and detailed three dimensional fuel rack model was used. At first, a short study was performed in order to pick up the neutron absorber material for absorber rods. Cadmium and hafnium were considered as candidate materials. Cadmium was chosen due to its availability. Later, an analysis was performed about the required number of uniformly mixed absorber rods in the lattice needed to sustain the subcriticality of the storage when pitch is decreased from rack design pitch of 8 cm to contact pitch, assuming that the absorber rods remain in their proper positions. Next, it is shown that, due to random mixing of the absorber rods during lattice compaction, supercriticality configurations cannot be completely excluded. Question arises about the probability for such event. For this purpose, a probabilistic study was made, sampling the probability density functions for random absorber rods lattice loadings. The results show reasonably low probabilities for supercriticality even for fresh 12 wt% enriched standard TRIGA fuel stored in the spent fuel pool. (author)