Respiratory protection program violations earned U.S. companies $2.6 million in OSHA-levied penalties last year. Here are the most-cited industries:

OSHA has cited Adams Thermal Systems Inc. in Canton with 51 safety and health violations following a February inspection prompted by a complaint alleging multiple concerns at the coolant core manufacturing facility. Proposed penalties total $225,000.

OSHA has cited Simtek Inc. for alleged repeat and serious violations of workplace safety standards as well as failing to correct eight hazardous conditions cited during a 2011 OSHA inspection that was prompted by a worker injury.

OSHA has cited Wal-Mart Stores Inc. for alleged repeat and serious violations of workplace safety standards at the company’s Super Center store in Cobleskill, NY.

OSHA has cited North Royalton-based DiGioia-Suburban Excavating for two willful safety violations after discovering that workers were allowed to ride inside an excavator bucket to access a trench at a Bowling Green job site on Nov. 17, 2011. 

An OSHA investigation begun after a worker was crushed to death in a coating machine while attempting to clear a jam has resulted in numerous citations against a New Jersey company.

A feed processing company that prevented OSHA from inspecting its facility has been found in civil contempt of court and ordered to pay nearly $42,000 in fines.

OSHA has cited Bath Iron Works, a General Dynamics company, for alleged repeat and serious violations of workplace safety standards at its Bath shipyard in Maine.

OSHA has cited Shawnlee Construction LLC for fall hazards identified during the construction of a new public safety building in Montville.

An unreported fire led to a complaint that led to an OSHA investigation -- and 13 violations against an Ohio auto parts manufacturer.