https://automation.honeywell.com/jp/ja/products/sensing-solutions/gas-and-flame-detection/portables/single-gas/toxirae-pro-lel-personal-monitors-for-combustible-gases
ToxiRAE Pro LEL Personal Monitors for Combustible Gases | Honeywell
personal monitorscombustible gasesprolelhoneywell
https://www.uspto.gov/web/patents/classification/cpc/html/defF23L.html
CPC Definition - F23L SUPPLYING AIR OR NON-COMBUSTIBLE LIQUIDS OR GASES TO COMBUSTION APPARATUS I...