This CCTV footage, provided by the National Fire Agency, shows workers at the Aricell battery factory trying to extinguish a fire at a lithium battery plant in Hwaseong, Gyeonggi Province, Monday. Five Koreans and 18 foreign nationals were killed in the blaze. Yonhap

The National Institute of Chemical Safety, an executive agency under the Ministry of Environment, announced, Thursday, that it will revise guidelines for five hazardous chemicals following a deadly fire at a lithium battery plant in Hwaseong, Gyeonggi Province, on Monday.

The tragedy that took 23 lives has triggered a debate over the use of conventional fire extinguishing methods involving water.

The ministry's key information guide contains the dangers of 97 types of hazardous chemicals and instructs how to prevent disasters and fires in case of leakage. The document is distributed to safety managers and those who handle "substances requiring preparation for accidents" in the workplace.

"Substances requiring preparation for the accident" refers to chemicals that are highly likely to cause chemical accidents and severe damage due to their acute toxicity or volatility, as designated and announced by the environment minister. Lithium is not one of them.

The safety agency explained that the information guide had errors on five substances — ethylene oxide, sodium cyanide, toluene-2, 4-diisocyanate, trimethylamine and acryloyl chloride.

For example, sodium cyanide is highly reactive with water and generates toxic hydrogen cyanide gas when it comes into contact with water. However, the existing guide states that the substance "does not react with water and water may be used as an extinguishing agent."

The institute plans to revise the guide after calculating water-responsive molecular dynamics of substances with incorrect information.

Firefighters initially considered using dry sand to extinguish the fire, but decided on water because the lithium in the primary battery was only in a small quantity and the battery plant had already burned down before the extinguishing work began.

The blaze also revealed the country's lack of preparation for fires involving combustible metals.

Fires caused by metals such as lithium require different extinguishing agents, and there are no approved technical standards for fire extinguishers designed for such fires.

In response, the government plans to pursue research on extinguishing agents for chemicals such as lithium from next year.