Injured by Gas Explosion RICHFIELD, Wis., Nov. 24 (/P)— n explosion, believed caused by he ignition of gas escaping from re- rigerating equipment, burned Otto Clippel, proprietor of a meat mar- set, critically and caused injuries ;o three other men yesterday. The three, Peter Margraf, Chester ilarleb and Aloys Yogerest, noticed ;he'gas odor-while in a tavern in ;he same building as the meat mar- tet. They notified Klippel and then went with him to investigate. :. They told Deputy Sheriff Robert Laubenheimer that Klippel apparently apparently pulled the switch on the refrigerating refrigerating machinery and a spark caused the explosion. There was little damage to the building.