WEYMOUTH -- The firefighters’ union is pushing back against Mayor Robert Hedlund’s selection of South Shore Health System as the town’s ambulance provider, arguing that the company is “ill-equipped” to provide coverage.

Colin Confoey, a lawyer for Local 1616 of the Professional Firefighters of Massachusetts, said in a letter to Hedlund on Wednesday that the selection of South Shore Health System will have a “drastic impact” on the safety of firefighters responding to emergencies and will affect their work conditions. Confoey said Local 1616 demands to bargain with the town over the impacts, such as workload and training.

Hedlund announced Monday that he and a five-member committee unanimously selected South Shore Health System, the parent organization of South Shore Hospital, as the town’s new ambulance service provider as of July 1. Fallon Ambulance Service, the town’s current provider, and Weymouth-based Brewster Ambulance also applied for the contract.

Fire Chief Keith Stark, Police Chief Richard Grimes, Emergency Management Director John Mulveyhill, Public Health Director Daniel McCormack and Hedlund’s chief of staff, Ted Langill, reviewed and rated the three proposals.

Jim Young, president of Local 1616, said Thursday that despite several requests, members of the union were excluded from the selection committee. He said other communities often involve not just the chief but union leaders as well.

“Who we partner with has a huge effect on the conditions of our employment and what we do every day,” Young said. “We’re the ones responding to houses when people call us, and who else comes is really important. The chief isn’t going out and doing medical calls. We’re doing the calls.”

Since it was his first time awarding an ambulance contract, Hedlund said his administration looked at the practices of other communities, many of which he said do not involve the union in the process.

“We went to great lengths to make it as open and transparent as possible,” Hedlund said. “Throughout the process, (the union members) made their preferences known to us as to who they wanted to see win this, and we considered that.”

Hedlund said not everything in South Shore Health System’s proposal will end up in the final contract. He said his administration will meet with the union to hear and address their concerns before drafting the ambulance contract.

Young said South Shore Health System’s inexperience as a primary 911 responder troubles union members. The company has provided emergency medical services since 1992 and medical oversight of EMTs and paramedics across the region for decades, though it has never served as the primary 911 responder for a community before.

“Both Fallon and Brewster have been doing this for years and doing it well, and (South Shore Health System) is basically a start-up company,” Young said. “It might be a good company, but we’ll learn that on the backs of my guys and the residents of Weymouth.”

As of Thursday, Young said he had no idea how South Shore Health System planned to handle one of the most crucial aspects of emergency responses: 911 calls. The organization does not have its own dispatch center equipped to answer 911 calls, known as a public safety answering point.

In an emailed statement, Susan Griffin, a spokeswoman for South Shore Health System, said the organization has existing “dispatch infrastructure and capabilities” and plans to partner with an established public safety answering point.

“We are confident in our abilities and certain that the mayor and (the committee) made a decision that best benefits the town and its residents,” she said in the email.

Hedlund said Police Chief Richard Grimes and Fire Chief Keith Stark are “more than comfortable with the dispatch arrangement,” which the town and South Shore Health System are working out.

South Shore Health System will keep two advanced-life-support ambulances with two paramedics and a basic-life-support ambulance with two EMTs in town around the clock. A second EMT-staffed ambulance will be in town 16 hours daily. An advanced-life-support field supervisor and a paramedic will be on duty at all times in a separate vehicle. The town will also have access to 10 backup ambulances for 16 hours a day.

Young questioned the availability of backup ambulances when several calls come in at once and South Shore Health System is transporting patients from the hospital or providing mutual aid to another community.

“It’s an issue of public safety,” he said. “Why do we have to sign on to be an experiment? If it fails and a call is missed or delayed, then what?”

Griffin said South Shore Health System expects to continue existing mutual aid agreements with nearby ambulance companies.

Jessica Trufant may be reached at jtrufant@ledger.com.