The employer shall ensure at a construction site of a building or other construction work that-
(a) barricades and warning signs are erected along every side throughout the length and breath of a building or other construction work to be demolished to prevent unauthorized persons from entering into the site of such building or other construction work during demolition operations;
(b) during the demolition of an exterior masonry wall or a roof from a point more than twelve meters above the adjoining ground level of such wall or roof, if persons below such wall or roof are exposed to falling objects, suitable and safe catch plat forms shall be provided and maintained at a level not more than six meters below the working level except where an exterior built up scaffold is provided for safe and adequate protection of such persons;
(c) suitable and standard warning signs in accordance with national standard are displayed or erected at conspicuous places or position at the workplace.