danger asbestos removal in progress warning signboard - concept wall against the intrusion of unauthorized persons

placard asbestos removal construction material building activity industry architecture site alert air pollution mesothelioma sign signboard warning signpost dangerous danger roof testing abatement fibers asbestoscement removing fiber tumor carcinogen lung cancer risk dust amiante asbestosis safety environmental damage cancerous illness carcinogenicity fibrous toxic substance waste aging process sickness particles inhalation hazard