There is a serious danger lurking in excavation work, which is often taken too lightly. The accident that happened in Espoo's Mankkaa is a sad reminder of this fact.
Two men were killed on May 9.5.2014, XNUMX at the construction site of a townhouse company in Mankkaa, Espoo. A tragic work accident was caused by a trench collapsing on the builders.
A large proportion of serious accidents in the infrastructure sector are trenching accidents. The cause is usually a trench collapse or falling into a trench. On average, one trench collapse leading to a serious accident occurs at construction sites in southern Finland each year. In three out of four cases, the accident victim has died.
"At the moment of a slump, there is very often normal routine work going on. The foundation and foundation conditions have not been more demanding than usual. Accidents have also occurred in shallow trenches less than two meters deep, for example during the excavation and installation of district heating pipes," says INFRA ry CEO Paavo Syrjö.
Violation of safety regulations has been behind almost all cases. The excavation work has not been properly planned, implemented or supervised.
The Occupational Safety and Health Act gives clear guidelines
According to the law, the developer is responsible for the planning and production control of the construction work. It must draw up a safety document using qualified designers, which assesses the dangers of excavation work and presents the methods for their elimination.
"It is essential that contractors can prepare for the costs caused by subsidizing the trenches during the tender calculation phase," Syrjö reminds.
Safety during work is the responsibility of the main contractor, who must draw up a safety plan and an excavation plan for the site and take care of their implementation and safety inspections. Subcontractors are responsible for the safety of their own employees. Employees have the right to refuse dangerous work.
Accidents can be prevented with the right support
"Accidents could be prevented by properly supporting the trench. Only in rough types of soil can it be enough to slope or step the trench, but you always need an opinion from an earthworks or geotechnical expert," says INFRA's safety expert Ari Kähkönen.
"Supporting the trench is the only reliable method when the trench wall is vertical. Steel punching or ready-made retaining wall elements are generally used for support," continues Kähkönen.
Together with its partners, INFRA ry produced a guideline on trench safety in 2013. A pocket-sized guideline should be in the back pocket of every builder.
"Accidents are terrible situations for both employees and employers. We hope that the investigation of the Espoo case progresses well and that the lessons will be learned from what happened. We don't want any more news like this," concludes Paavo Syrjö.
ADDITIONAL INFORMATION:
Paavo Syrjö, CEO, INFRA ry; tel. 040 560 1803
Ari Kähkönen, expert, INFRA ry; tel. 050 511 6770
INFRA ry is an industry and employer organization of infrastructure construction professionals. Our 1600 member companies build and maintain roads, terminals and vital technical networks that carry water, heat, electricity and information. INFRA's members produce the vast majority of Finland's infrastructure services. We are part of Rakennusteollisuus RT and the Finnish Confederation of Business and Industry EK.