A common minimum level of preparedness is defined through the infrastructure standard (N-1 indicator) which is expressed using several separate indicators together describing the ability of a country to satisfy total gas demand in the event of disruption of the single largest gas infrastructure. If in the event of interruption, it is possible to rearrange deliveries without any supply disruption, the N-1 criterion is met. A common minimum criterion on security of gas supply was tested on the example of the Baltic State. The empirical analysis performed showed that the level of gas security of supply in the region cannot be evaluated based only on the infrastructure standard. The complex solution should be applied - infrastructure standard and risk scenarios or similar methods of risk analysis as well as the existing N-1 indicators’ calculation formula must be modified.