Demolition is a dangerous part of construction work and manual demolition in particular can cause serious injuries to the workers involved. The most common problem that affects workers during a manual demolition is the unexpected collapse of the wall being demolished.
Earlier this year a wall which was being demolished manually unexpectedly collapsed on a worker in Sydney causing his death. The bottom section of the wall had been broken with a sledge hammer and the entire wall was to be removed to enlarge an area. The wall was weak because the bottom section had been knocked out so the wall collapsed onto the worker and crushed him.
Workers should be aware of the correct sequence that needs to be followed during a manual demolition. This type of task involves working with dangerous tools that also can present a hazard to workers if not used correctly. These include jackhammers, sledge hammers and picks which you should be trained on before using. Masonry and brickwork should be taken down evenly and demolished in reverse order to their construction.
Employers and contractors should ensure that workers are competent and have received training and instructions on safe demolition methods before even starting demolition. Ask workers to produce competency certificates to prove that they are certified. Employers also need to ensure that the process is supervised by a person qualified and competent to do so.
When removing entire wall sections using manual demolition methods that incorporate hand tools, such as jackhammers, sledge hammers and picks, workers should avoid weakening the wall. Weakening the wall was the cause of death for the worker in Sydney earlier this year. Weakening of the wall can be avoided by never taking down multiple rows of brick at once or starting at the bottom of the wall. Workers should remove the top row of bricks using a hammer and chisel and finish an entire row before starting the next.
Another possible hazardous situation may occur when removing a portion of a wall where masonry will remain above the opening. This is often done to install a door or window. Workers should ensure the upper area of masonry should be supported prior to commencing demolition and the demolition should commence at the top of the intended opening.
Bystanders and workers on the site that are not involved in the demolition should be kept away from the area. This involves setting up exclusion zones to keep unauthorised people outside of the area where the wall may collapse or debris may fall.
Employers should consult workers when developing a safe work method statement before beginning the demolition work as is done with all dangerous construction activities.
Part of working safely on a construction site involves workers wearing the appropriate PPE and employers providing this PPE and training on it. Safety glasses, a dust mask, gloves and long-sleeved clothes should be worn as protection from flying objects and dust. When the demolition process produces excessive noise, hearing protection should be worn. If the demolition is being done at a height, fall protection should be in place and operating effectively. Workers must never work from the top of a wall that is being demolished.
A wall should not be permitted to stand unless it is effectively supported against collapse. Before demolishing a wall, it is important to ensure that the wall is not a load bearing wall and is not providing support for other walls.
Undoubtedly the worker that was killed earlier this year was not sufficiently trained on how to demolish a wall safely. Sadly it is too late for him, however other construction workers should not fall victim to the same fate. Do not attempt to demolish a wall if you are unsure of how to safely do so. Also if a supervisor or superior asks you to do something that could put your safety in jeopardy, do not do it because your life is worth more than any job.