The content and method of 1
1. 1 The evaluation basis is occupational health laws, regulations and technical standards such as Hygiene Standard for Design of Industrial Enterprises, occupational exposure limits-Chemical Hazardous Factors, occupational exposure limits-Physical Factors, Occupational Hazards Classification Catalogue, Occupational Hazards Evaluation Standard for Construction Projects, etc. The feasibility study report of this construction project is the basic data.
1.2 evaluation scope: identification of occupational hazard factors and evaluation of control effect for a winding core transformer production project in Baoding. Including general layout, production technology and equipment layout, health protection facilities, personal protection measures, auxiliary clinic settings, occupational health management measures, etc.
1.3 both the person in charge of quality control evaluation and the auditor are qualified and experienced in occupational hazard evaluation, and work is carried out according to the evaluation procedure on the basis of comprehensive collection of relevant information of the project. On-site sampling and laboratory testing are carried out in strict accordance with the current national standards, and the instruments and equipment used have been metrological verified and operated by professionals with inspection qualifications.
2 Results and analysis
2. 1 Project Introduction The project consists of corrugated oil tank processing workshop, iron core processing area, paint processing area, transformer finished product warehouse, insulation processing area, product assembly area, product experiment area, product drying area, coil winding area, office building and second-phase standby area. The main production equipment includes corrugated oil tank production line, aluminum foil winding machine, automatic winding machine, silicon steel sheet cutting machine, winding core production line, body assembly line, annealing furnace, vacuum oil filling, drying vacuum tank, testing equipment and painting drying room. Products are oil-immersed distribution transformers. A single transformer with an annual output of 30 KVA ~ 500 KVA, 65,438+00 KVA ~ 35 KVA, 65,438+0.10,000, with a total capacity of 3 million KVA.
2.2 General Layout and Layout The production workshop is arranged by functional partition, taking into account factors such as hygiene and environmental protection, as well as domestic water, industrial wastewater discharge and living facilities. The spray booth that produces a small amount of xylene is arranged at the east end of the tanker room, which will not affect workers in other processes because of less harm. The welding process is concentrated in a specific area, which reduces the influence of dust on other operators.
2.3 Main production process Brief introduction of oil tank processing: The corrugated oil tank is formed by using high-quality steel plates on the automatic production line of corrugated oil tank, and then the corrugated oil tank is welded with the tank body by automatic argon arc welding machine (mobile), and then the strength leakage test of the oil tank is carried out (using compressed air for leakage test). The qualified corrugated oil tank is refined oil tank. Derusting: the oil tank enters the closed shot blasting room, and the shot material sprayed by the automatic shot blasting equipment at high speed carries out high-speed derusting and cleaning on the workpiece to achieve the effect of cleaning and derusting the workpiece. Painting: Oil tank painting is carried out in the closed DPS pump-free water curtain painting room, and the paint mist generated is purified by the water curtain (containing paint mist treatment agent) gas collection box and then discharged from the 15 m exhaust pipe. Core winding: Cut the wound silicon steel sheet into required strips on the longitudinal cutting line of core winding, and roll it into qualified iron core on the core winding machine, then anneal (use electricity) the wound iron core according to the process requirements, and check the annealed iron core, and the finished iron core is qualified. Winding assembly: The coil of closed winding core transformer is to wind the selected copper conductor on the qualified winding core to form the transformer body. After the blank is dried, the semi-finished product is inspected, and the transformer assembly is carried out after it is qualified, that is, the transformer blank is put into the prepared oil tank, the blank is fixed, vacuum oil injection (25# transformer oil) is carried out, and finally the finished product is inspected and put into storage after it is qualified.
2.4 The noise of occupational disease prevention measures mainly comes from shot blasting machine, corrugated molding machine, slitting machine, extrusion molding machine, air compressor, vacuum pump and other equipment. Cutting machine, shot blasting machine, corrugating machine and extrusion machine adopt low-noise equipment, and adopt plant sound insulation and foundation shock absorption measures. Air compressor and vacuum pump adopt sealing, muffler installation, plant sound insulation and sound absorption measures. In the process of oil tank welding, two axial fans were set up, with the total air exchange capacity of 12 km3/h, and several exhaust fans were installed, which effectively reduced the welding dust concentration in the workplace. The shot blasting room in the process of derusting is a closed workshop, with its own bag dust removal system and 15 m exhaust pipe, and the purification efficiency is ≥90%. In the oil tank painting process, DPS pumpless water curtain spray booth is used for paint mist treatment, which is discharged through 15 m exhaust pipe. The purification efficiency is ≥96%, and the treated air volume is15 km3/h. A small amount of xylene will escape during the painting process. Workshop ventilation device and two axial flow fans are adopted, and the total ventilation times are12km3/h. ..
2.5 Occupational Health Management and Personal Protective Equipment According to the occupational hazards generated by the project, the company has formulated an occupational health management system, an occupational disease hazard factor detection system, an occupational health physical examination system and a labor protective equipment management system. Implemented by the Personnel and General Services Section. According to the types of occupational hazards at work, distribute personal protective equipment such as dust masks, gas masks and noise-proof earplugs and replace them regularly. There are dressing rooms, bathrooms and other auxiliary toilets.
2.6 Detection results and evaluation of occupational hazard factors
2.6. 1 Through occupational health investigation and production process analysis, it is determined that the main occupational hazard factors in the production process of this project are: noise generated by mechanical equipment such as corrugated molding, shot blasting, longitudinal shearing, extrusion molding and plate shearing machine; Welding dust generated in the process of oil tank welding and other dust generated in the process of shot blasting rust removal; Xylene produced during painting. According to the requirements of Monitoring and Sampling Standard for Hazardous Substances in Workplace Air GBZ 159-2004 and Evaluation Standard for Occupational Hazards of Construction Projects, noise, dust and xylene were sampled and detected. See table 1 ~ 3 for the results.
Reliable occupational health engineering measures were taken in the painting process, and the detection results of occupational hazards all met the requirements of GBZ2.2—2007 occupational exposure limits of Hazardous Factors in Workplace.
2.6.2 The main occupational hazards existing in this project have an impact on health noise: long-term exposure to industrial noise can cause various adverse changes in workers' bodies and specific hearing system damage. It can cause tinnitus, earache, dizziness, irritability, insomnia, memory loss and other symptoms, causing temporary hearing threshold displacement, permanent hearing threshold displacement, high-frequency hearing loss, voice hearing loss and even noise deafness. Causes nonspecific adverse changes in the nervous system, digestive system and endocrine system of workers; As a result, workers' attention, physical agility and coordination are reduced, work efficiency and quality are reduced, and the possibility of production accidents and industrial accidents is increased. The occupational disease that can be caused is noise deafness. Dust: Productive dust refers to solid particles that are formed in production and can float in the air for a long time. It is an important occupational harmful factor that pollutes the working environment and endangers the health of workers.
A variety of occupational lung diseases, including pneumoconiosis [3]. Long-term exposure to high-concentration dust can cause systemic diseases such as pneumoconiosis, mainly pulmonary fibrosis. It is characterized by shortness of breath, chest tightness, chest pain, cough, expectoration and other symptoms, and it is easy to be complicated with tuberculosis, pulmonary infection, cor pulmonale and spontaneous pneumothorax. Dust can also cause chronic rhinitis, pharyngitis and dry keratinization of skin. Occupational disease caused by welding dust is welder's pneumoconiosis. Xylene: A colorless, transparent, aromatic and volatile liquid with ortho, meta and para isomers. Boiling point 138.4 ℃~ 144.4℃, steam specific gravity 3.66, insoluble in water, soluble in ethanol, acetone, chloroform and other solvents. [3] Skin contact can cause skin erythema, dryness, degreasing, chapping, even conjunctivitis, keratitis and other symptoms. Excessive inhalation can cause dysfunction of central and autonomic nervous system, manifested as headache, dizziness, memory loss, insomnia, abnormal sensation, loss of appetite, nausea and vomiting.
2.7 Occupational Health Surveillance According to the requirements of the Administrative Measures for Occupational Health Surveillance, the enterprise has carried out occupational health examinations for employees exposed to drugs, and no occupational diseases, occupational injuries and occupational contraindications have been found in the past three years.
3 evaluation conclusion
The general layout of the construction project is reasonable, the division of labor among buildings in the plant area is clear, the layout of each production process is reasonable, the technology is advanced, and the occupational disease harm is small, which meets the requirements of the Hygienic Standard for Design of Industrial Enterprises and the Code for General Layout Design of Industrial Enterprises. The construction project has adopted reliable occupational health engineering measures in the control of occupational hazards, and formulated corresponding occupational health management measures. The construction of occupational health management system and occupational health management system basically meets the requirements of the Law on the Prevention and Control of Occupational Diseases. Auxiliary facilities such as dressing rooms and toilets can meet the needs of workers. The occupational hazards existing in this project are mainly noise, dust and xylene. According to the Management Measures for Classification of Occupational Hazards in Construction Projects, this project belongs to a construction project with mild occupational hazards. To sum up, the project design has taken corresponding health protection measures for the existing occupational hazards. Through on-site investigation and testing, it is considered that the occupational health engineering measures and management measures taken against the occupational hazards caused by the project are necessary and feasible. The occurrence of occupational diseases can be controlled and the health of workers can be protected under the condition that the occupational disease protection facilities operate normally, personal protective equipment is used correctly and health monitoring work is in place.
Four suggestions
Check DSP spray booth regularly to maintain its good operation and reduce the escape of xylene during spray painting; Focus on the harm of welding dust, strengthen the management of welding operation between tankers, ensure the normal operation of axial flow fans and exhaust fans, and equip qualified personal protective equipment for welding operators to avoid health damage; Conduct occupational health examination for employees in this position every year, and establish health monitoring files.