Yesterday 2 Bangladish near to death when the wall collapsed and hit 2 Bangladish worker when doing the renovation job at Ipoh.The concrete wall suddenly collapsed and broken the one of Bangladish hand and same with the other one.Why this accident happen?.The weight of concrete wall per square metre are around 4.8 kn/m2 or 0.48 ton/m2 or 480 kg/m2 more than 4 times than human weight.
There are several MOS should be follow before any demolition work can be start.Below are the demolition report or MOS for demolition of building should be strictly follow by all the builders to avoid any accident like yesterday.
- Precautionary measure
- Hoarding
- Requirement-hording should provided along the full length of the site boundary adjacent to the public access especially at the crowded places like town area or urban area
- Dimension-The height of the hording must be 2.0 m fro the ground level
- Desgn-The hording must be design to sustain the wind load
- Construction-a),The construction of hording either by timber or steel frame with metal decking as a panel.The connection between them is either by rivet or nails.b),the column must be in the ground at least 600 mm and covered with a concrete as a base.
- Scaffholding
- Scaffholding-a).Metal scaffholding shall be used for top down demolition works.b)Erection of metal scaffholds must be by trained workmen and competent person.c)Support of scaffholds should have adequate strength to hold vertical load plus own weight imposed on the scaffholds.d).The scaffhold must be anchored to the rc beam or slab.e)The unbraced sections shall not be higher than 2 m height from the nearest anchor.
- Screen Cover
- a).Two layers of protective screen shall be placed over the scaffholds to completely enclose the building structure for retaining dust and small debris,b).Tarpaulin and nets shall be need to cover the exterior face of the scafhold.c).Tarpaulin shall placed over the net.
- Protection of properties
- General-a).To protect a lateral load and I beam shall be fixed between column to column.b).Every slab and beams must have a temporary support before star a demolition works,c).The material for temporary support can be form steel or good timber.
- Party wall and external wall-a).Exposed external wall and party wall shall be protect from weather either by tarpaulin or water proofing.b).The raking timber shall be provided to support external wall or party wall.