Dan Jacobs, an electrician from the firm who had a family member saved by the helicopter and its crew, nominated the charity.
For the last year workers at the company headquarters in Shaftesbury held a series of fundraisers.
These included a staff raffle, bake-off, bingo, quiz night and even a sky dive by administration manager Steph Hewis.
The cheque was presented to Leanne Colverson from the Dorset and Somerset Air Ambulance.
Simon Morgan, Director of Wessex Group, said: “Our staff have raised this sum by themselves, organising a series of fundraising events.
“The air ambulance was a cause we donated money to in 2013 when we were marking our 50th anniversary and it remains an important service for many people.
“It relies on donations to operate and it was the most popular choice among staff.
“We had aimed to raise £5,000, but ultimately donated a cheque for £6,647.
“Our staff have really made a great effort and we will be supporting another charity next year.”
The Wessex Group is a family business and consists of a number of companies that operate in fire and security, electrical, HVAC and plumbing, renewable energy and property maintenance.
Notes to editors: Wessex Group is a collection of companies based in Shaftesbury, Dorset, but working across the south. It began in 1963 when Tony Morgan set up his own electrics firm. The group now consists of numerous companies that install and/or maintains electrics, heating, air conditioning, plumbing, renewables and fire and security systems. Tony’s sons Simon and Alistair now head the firm.
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