The Phanatic's new hot dog launcher propels
franks with a tank of compressed nitrogen. The old launcher used carbon dioxide.
Robert Levis, chairman of Temple University's chemistry department, said the change
from carbon dioxide shouldn't make much difference in firing just one shot. It's the
pressure that matters. But for repeated firing, he said, nitrogen has the edge.
"You're just not going to get that many rapid-fire shots with the CO2 in comparison
with the same amount of nitrogen," Levis said.