According to JTBC News, the National Forensic Service’s forensic results,
Do not block the gas hose that was previously connected to install additional cooking appliances.
analyzed as the cause.
+ This is a different article, but according to CJB News, 2 fryers and 1 cooking utensil should have arrived, but 1 fryer was delivered late, so it was installed as above. It is illegal to drill one in advance, but it is said to be the custom of gas construction companies.
Additionally, the article pointed out that one of the blind spots is that the Korea Gas Safety Corporation’s confirmation process is not required for changes in use or additional construction.