In light of the fire incident that occurred in a toilet in the Green World (GW) construction zone on 28 March 2024 and other incidents, the Japan Association for the 2025 World Exposition (hereinafter referred to as “the Association”) has consulted with experts to compile safety measures for methane gas and other substances during the period of Expo 2025 Osaka, Kansai, Japan (hereinafter referred to as “the Expo”) and published them on 24 June, 2024.
As part of the efforts to provide information to visitors, the Association decided to a the results of methane gas concentration measurements at the Expo site during the period of the Expo in an easy to understand format on a daily basis.
The Association is continuously measuring methane gas concentrations across the Expo site, and since 13 April 2025, the opening day of the Expo, we have been announcing the results twice a day on our official website. We have now compiled the methane gas results for the first month after the opening of the Expo.
The measurement results are summarised below:
* Note: The “standard value” is 1.5 vol% as stipulated in the Ordinance on Industrial Safety and Health. The lower explosion limit of methane gas is 5 vol%.
・No methane gas levels the same as or above the standard value were detected inside buildings or around paths.
・The Association is also taking measurements in the underground pits for outdoor equipment, which are unlikely to be entered by people, in order to monitor overall methane gas emissions at the Expo site. Pit covers have been replaced with metal grating covers, which offer better ventilation, on pits where concentrations above the standard value were detected or were deemed likely to occur.
・Methane Gas Concentration Measurements at the Venue Expo Site (13 April – 12 May 2025)
・Methane Gas Countermeasures in Underground Pits for Outdoor Equipment (as of 12 May, 2025)