Ann Arbor Township-based quality auditing not-for-profit NSF International has acquired a seafood quality inspection firm.

NSF bought Lynnwood, Wash.-based Surefish Inc., a 65-year-old firm with 17 employees, company officials said. NSF will continue to operate the firm as a subsidiary called NSF Surefish.

Surefish adds to NSF's diverse roster of auditing and certification services. Surefish assesses the quality of seafood for restaurants, retailers, fisheries, wholesalers and other groups.

“NSF Surefish services will help seafood companies comply with best industry practices and standards throughout the world, while providing these companies with comprehensive training, auditing, certification services and seafood quality programs,” said Tom Chestnut, NSF International's vice president of supply chain food safety and quality, in a news release.

NSF has more than 400 employees at its headquarters in Ann Arbor Township. The firm has about two dozen offices globally and some $150 million in annual revenues.

NSF spokeswoman Greta Houlihan said it's unclear whether the company would have to hire employees in Ann Arbor to support the acquisition. NSF expects to maintain all offices associated with Surefish.

"We may need some additional people, but at this point it's difficult to determine that," Houlihan said. "The acquisition definitely contributes to NSF's overall growth."

Contact AnnArbor.com's Nathan Bomey at (734) 623-2587 or nathanbomey@annarbor.com. You can also follow him on Twitter.