Lakewood, Colorado-based Mesa Laboratories, a manufacturer of electronic instruments for industrial and health care applications, reported Tuesday that it has promoted Dr. John J. Sullivan to chief executive officer and board member. Sullivan, Mesa Labs said, succeeds Luke R. Schmieder, who has served as CEO since founding the company in 1982. The firm explained that Schmieder is retiring and thus resigning from his CEO and treasurer roles but will continue to chair its board of directors. Sullivan joined Mesa Labs in 2004 as vice president of sales and marketing, the company said, adding that he was elevated to the role of president and chief operating officer in 2006. Sullivan will retain his position as president, Mesa Labs said.