Danger warning signs What is danger?

Hazard source refers to the location, area, place, space, post, equipment and its position in the system, which has the potential danger of releasing energy and substances under the action of certain triggering factors, can cause personal injury and can be transformed into accidents. Its essence is the source point or position with potential danger, the source of accidents, the core of energy and dangerous substances concentration, and the place where energy comes out or erupts. Danger exists in a certain system, and the scope of danger is different in different systems. For example, nationwide, a specific enterprise (such as an oil refinery) is a hazard source of dangerous industries (such as petroleum and chemical industry). From the enterprise system, it may be that a workshop or warehouse is a hazard source, and the workshop system may be a device or a hazard source; Therefore, the analysis of hazard sources should be carried out according to different levels of the system. Generally speaking, hidden dangers may or may not exist, and hidden dangers with hidden dangers of accidents must be rectified in time, otherwise accidents may occur at any time. In practice, the control and management of hidden dangers of accidents are always associated with certain hazards, because there are no dangerous hidden dangers, so they cannot be controlled; The control of dangerous sources is actually to eliminate or prevent hidden dangers of accidents. So in practice, these two concepts are sometimes misused. Hazard sources should consist of three elements: potential hazards, existing conditions and trigger factors. The potential danger of hazard sources refers to the degree of harm or loss that may be caused once an accident is caused, or the energy intensity or quality of dangerous substances that may be released by hazard sources. The existence conditions of hazards refer to the physical, chemical and restrictive conditions of hazards. For example, the pressure, temperature and chemical stability of substances, the firmness of pressure vessels, obstacles in the surrounding environment, etc. Although the trigger factor does not belong to the inherent attribute of hazard sources, it is the external cause of the transformation of hazard sources into accidents, and each type of hazard source has corresponding sensitive trigger factors. For example, flammable and explosive substances, heat energy is its sensitive fuse, and for pressure vessels, pressure rise is its sensitive fuse. Therefore, a hazard source is always associated with the corresponding trigger. Under the action of trigger factors, the hazard source is transformed into a dangerous state, and then into an accident. Classification of hazard sources The hazard sources in industrial production are generally divided into five categories: (1) toxic, radioactive, corrosive and infectious disease pathogens; (two) the hazards of boiler and pressure vessel facilities; (3) Hazard sources of electrical facilities; (4) Hazard sources in high-temperature operation areas; (5) Radiation hazards; Identification of hazards: the process of identifying the existence of hazards and determining their characteristics. 1, foundation pit support and dewatering engineering Foundation pit support engineering refers to the excavation of a foundation pit (groove) with a depth of more than 5m (including 5m) and the construction of the supporting structure; Or the foundation pit is less than 5m, but the geological conditions and surrounding environment are complex, and the groundwater level is above the pit bottom. 2. Earthwork excavation refers to the earthwork excavation of foundation pits and troughs with excavation depth exceeding 5m (including 5m). 3, template engineering template engineering tools, including sliding mode, large template and special structure template engineering, etc. 4. Lifting and hoisting works. Scaffolding works are more than 24m high? 50 m floor-standing steel pipe scaffold; Cantilever scaffold; Hanging basket scaffold; Unloading platform, etc. 6. Demolition blasting engineering adopts manual and mechanical demolition or blasting demolition engineering. 7. Temporary power consumption projects. Curtain wall installation and construction of other dangerous engineering buildings; Tension construction of prestressed structure; Special equipment construction; Construction of grid structure and cable-membrane structure; 6m above the slope construction; 30m and above aerial work; The adoption of new technologies, new processes and new materials that may affect the quality and safety of construction projects has obtained administrative permission and there is no technical standard; Sub-projects that may affect the safety of facilities and residents around the site; Other professional, complex, dangerous, cross and other construction sites and operations prone to major accidents.