{"operation":"document","citation":"49 CFR 193.2421","title":"Cold boxes.","source_type":"regulation","agency":"Pipeline and Hazardous Materials Safety Administration","status":"historical","official":true,"published_on":null,"effective_on":"1999-10-01","summary":"(a) Each cold box in a liquefaction system must be equipped with a means of monitoring or detecting, as appropriate, the concentration of natural gas in the insulation space.\n\n(b) If the insulation space in a cold box is designed to operate with a gas rich atmosphere, additional natural gas must be ","machine_formats":{"json":"https://regulus.evalyn.ai/document/49-cfr-193-2421.json","markdown":"https://regulus.evalyn.ai/document/49-cfr-193-2421.md"},"app_url":"https://regulus.evalyn.ai/document/49-cfr-193-2421","source_url":"https://www.govinfo.gov/app/details/CFR-1999-title49-vol3/CFR-1999-title49-vol3-sec193-2421","body":"(a) Each cold box in a liquefaction system must be equipped with a means of monitoring or detecting, as appropriate, the concentration of natural gas in the insulation space.\n\n(b) If the insulation space in a cold box is designed to operate with a gas rich atmosphere, additional natural gas must be introduced when the concentration of gas falls to 30 percent.\n\n(c) If the insulation space of a cold box is designed to operate with a gas free atmosphere, additional air or inert gas, as appropriate, must be introduced when the concentration of gas is 25 percent of the lower flammable limit.","truncated":false,"body_characters":593}