The three-level protection principle and measure of dust

Dust means solid particles that can be suspended in the air. The dust produced in industrial production is called industrial dust. If industrial dust is not controlled, it will damage the working environment, endanger the health of workers and damage the machinery and equipment. In China, there are many industries and types of work that can produce dust, such as mining and quarrying of metal ores and non-metal mines, road building for infrastructure construction, tunneling and geological exploration, glass manufacturing, refractory and building materials processing. . The crushing, milling, sand removal and transportation of the foundry industry. The degree of dust damage to the human body depends on the amount of dust inhaled by the human body, the route of dust intrusion, the site of dust deposition, and the physical and chemical properties of the dust. Among assorted dusts, asbestos dust and dust containing free silica are most harmful to the human body. Asbestos dust not only causes asbestos lung, but also has carcinogenicity; dust containing free silica can cause silicosis, and dust containing more than 70% of free silica is more harmful to the human body. Different dust particles have different hazards to the human body. Dust from 2 microns to 10 microns is the most harmful to the human body. In addition, the charged dust, the less soluble dust, the harder dust, and the irregularly shaped dust are more harmful to the human body.

The main channels for dust intrusion into the human body include the respiratory system, eyes, and skin, among which the respiratory system is the main route. Dust on the human body's various systems is as follows: dust invades the respiratory system, it will lead to pneumoconiosis, lung dust deposition, organic dust caused by lung lesions, respiratory system tumors and local stimuli and other diseases; if dust invades the eyes, Can cause conjunctivitis, corneal opacity, eyelid edema and acute keratitis and other symptoms; dust invades the skin, can block the sebaceous glands, sweat glands, resulting in dry skin, vulnerable to infection, causing folliculitis, acne, dermatitis and so on. According to the type of dust concentration, dust-time national standard "level of industrial dust of hazard classification" (GB5817-86) provides that the production of dust contact with harmful levels of work is divided into five: 0 (hygienic conditions), Grade I ( mild hazard ) , Grade II ( moderate hazard ) , Grade III ( high risk ) , Grade IV ( extremely hazardous ) . According to relevant state regulations, enterprises and institutions should classify dust hazards of Class III and Class IV as dust control priorities. Occupational health supervision authorities at all levels should classify Class III and Class IV dust hazards as the focus of occupational health surveillance work. After classification testing, enterprises with dust hazards up to Class IV must be eliminated within one year. Otherwise, the occupational health supervision authority has the power to order them to stop production; the new, expansion, reconstruction, and technological transformation projects must be dust-damaged during trial production. Degree classification, where there are Class III, Class IV dust hazards, it is not allowed to formally put into production; Class II hazards, should not be promoted to state-level enterprises.

At present, the harmful effects of dust on people, especially pneumoconiosis, have not been specifically treated. Therefore, it is very important to prevent the dust hazards and strengthen the labor protection management of dust operations. Labor protection management of dust operations shall adopt the three-level protection principle: Primary prevention measures include: comprehensive dust prevention, that is, reform of the production process and production equipment, and the change of manual operations into mechanization, automation, and confinement and remote control; It may be possible to use materials that do not contain free silica or that contain low free silica instead of materials containing free silica; use wet processing wherever possible under the conditions required by the process; use personal dust-proof equipment for personal protection . Regular testing means that the dust concentration of the operating environment is regularly tested so that the dust concentration of the operating environment is within the allowable range specified by the national standard. The health examination is based on the relevant regulations of the state, and the workers shall be subject to a pre-employment health examination. The occupational contraindications, minors, and female employees shall not be allowed to work in taboos. Promote the basic knowledge of education and dust prevention. Strengthen maintenance The dust removal system must be maintained and managed so that the dust removal system is in good condition. The measures for secondary prevention include the establishment of a dust-relief agency responsible for personnel, the formulation of dust-prevention plans and various rules and regulations; the employees who are newly engaged in dust operations must carry out health inspections; and the workers engaged in dust operations must perform health regularly. Check and found that employees who are not suitable for dust control work should be promptly transferred. The main measures for tertiary prevention are: For employees who have been diagnosed with pneumoconiosis, they should be promptly transferred from their original job positions, arrange reasonable treatment or convalescence, and the social insurance treatment of patients should be handled in accordance with relevant state regulations.

The information in this article comes from the Internet and was reorganized and edited by China Rescue Equipment Network.