MAPP gas

MAPP gas was widely regarded as a safer and easier-to-use substitute for acetylene, but, early in 2008, its production was discontinued at the only remaining plant in North America that still manufactured it.

Plumbers, refrigeration and HVAC engineers and other tradesmen also value the high heat capacity of the MAPP/air flame; MAPP was until recently widely used, supplied in small to medium size containers.

Myhrvold recommends in Modernist Cuisine: The Art and Science of Cooking that MAPP gases should be used in preference to cheaper butane or propane as they produce higher temperatures with less risk of giving the food a gas flavour, as can happen with incompletely combusted gas.

The gas has a pronounced acetylene-like or fishy odor at concentrations above 100 ppm, due to the addition of substituted amines as a polymerization inhibitor.

The Occupational Safety and Health Administration (OSHA) has set the legal limit for MAPP gas exposure in the workplace as 1000 ppm (1800 mg/m3) over an 8-hour workday.

At levels of 3400 ppm, 10% of the lower explosive limit, MAPP gas is immediately dangerous to life and health.