The Sheffield-based group, which recently sold its scaffolding business, said the sale is part of its plan to focus on core operations.
The safety and workwear business earned revenues of £22m in 2010.
SIG, a leading European specialist supplier of insulation, interiors, exteriors and specialist construction products, said SIG Safety and Workwear is a leading distributor of personal protection equipment and workwear to a variety of market sectors throughout the UK.
Gross assets of the business at completion were £8m.
Chris Davies, SIG’s chief executive, said: “We are pleased to announce the sale of our SIG Safety and Workwear to Bunzl, which will provide the necessary scale and focus to take the business forward.
“This divestment, which follows the recent sale of our scaffolding business, is consistent with SIG’s key strategic initiative to improve performance by actively managing the group’s portfolio of businesses to focus on our core operations.”
Earlier this month, SIG sold its Beaver 84 scaffolding business to a French company for an undisclosed sum.
The scaffolding and fencing operation was sold to Altrad, a privately-owned French scaffolding manufacturer and hirer.
SIG’s strategic development director Andrew Greenaway said the Beaver 84 business has more scope for growth as part of Altrad.
“SIG maintains an active portfolio review process to assess the fit with other parts of the group and SIG’s ability to grow and develop each business going forward,” he said.
He said Beaver 84 has greater potential for growth within the Altrad Group.