Explosion
3) explosion - rapid chemical transformation of the environment, accompanied by energy release and formation of compressed gases;
Source: Federal Law No. 123-FZ dated 22.07.2008 (as amended on 10.07.2012) "Technical Regulation on Fire Safety Requirements"
3. Explosion - a process of releasing a large amount of energy in a limited volume over a short period of time, resulting in the formation of a shock wave, where pressure exceeds calculated values, leading to activation of explosion relief valves (if present), occurrence of residual deformations and (or) destruction of boiler components
Source: Order No. 4 of Gosatomnadzor of Russia, No. 98 of Gostorgtehnadzor of Russia dated 19.06.2003 "On approval and introduction into force of federal norms and rules in the field of use of atomic energy 'Rules for design and safe operation of steam and hot water boilers for nuclear power facilities'" (together with "Rules ... NP-046-03") (Registered by the Ministry of Justice of Russia on 10.07.2003 No. 4884)