How to choose suitable lighting fixtures according to the working environment?
People engage in all kinds of productive labor, mainly relying on vision to make a correct judgment on the external situation and take corresponding actions. Therefore, lighting (using natural light source) and lighting (using artificial light source) in the working environment are an important condition to ensure workers to work efficiently, comfortably and safely, and also an important factor to evaluate the safety of the working environment. Good lighting environment will make people feel comfortable and improve the sensitivity, accuracy and speed of vision. Avoid eye tension, relieve visual fatigue and improve work efficiency. Research shows that when the illumination in the workshop where the nib is produced is increased from 11 lux to 140 lux, the output of nib increases by 25%. 8%。 On the contrary, if the illuminance of the typesetting workshop is reduced from 200 lux to 20 lux, the typesetting efficiency will decrease by 25% and the error rate will double. Illumination is more significant for safe production. Poor ambient lighting makes it easy for workers to accept wrong information, which leads to wrong judgment and operation, and causes accidents. According to statistics, industrial accidents directly or indirectly caused by poor lighting account for 25% of the total. This percentage is considerable. There are two main requirements for illumination in the working environment: first, the illumination requirements mentioned above; Second, the quality requirements of light itself, including uniform light, stable light (no stroboscopic phenomenon), good light color effect (no color distortion of the irradiated object), no glare, etc. Then, what are the specific requirements for the selection and layout of light sources to improve the lighting conditions of the working environment? The following suggestions deserve the attention of safety workers. A, the working environment should ensure the appropriate illumination. The illuminance required by human eyes to produce normal vision is usually 50 to 75 lux. With the increase of illumination, the clarity and speed of human eyes' recognition of external things are correspondingly improved. At the same time, the fatigue of workers will also be reduced because of the reduction of human energy consumed by grasping external conditions. Some people have studied the relationship between the illumination of working environment and the relative fatigue of workers. Their research results show that when the illumination of working environment increases from 30 lux to 300 lux, the fatigue of workers decreases by about 40%. If the illumination continues to increase to 1000 lux, the fatigue level of workers will be further reduced to 50%, reaching the lowest point. If the illumination exceeds 1000 lux, the fatigue level will rise again because the workers feel the glare of the light. Therefore, excessive illumination is not desirable. In order to keep workers' eyesight above the level of no visual impairment, countries all over the world have formulated uniform standards for the minimum illumination required for various operations. Generally speaking, with the improvement of work fineness (defined quantitatively by the minimum size of the identified object), the required illuminance on the working surface also increases. For example, China's "Standard Value of Illumination on Working Face of Production Workshop" stipulates: engage in general work. Under the condition of mixed lighting (lighting combined with general lighting and local lighting), the minimum illumination shall reach 150 lux; Engaged in fine work, under mixed lighting conditions, the minimum illumination should be 300-500 lux. Second, try to use natural sunlight Daylight is the most energy-saving light source. Daylight is also the best light source. Using more sunlight in the working environment will help to improve the distribution of light and eliminate or weaken shadows. According to reports, the number of accidents in British foundry, shipbuilding, machinery manufacturing and other industrial departments in winter is almost twice as high as that in summer. One of the main reasons is that the sunshine time is short and the brightness is weak in winter, and artificial light sources are widely used in workshops for lighting. However, some inherent defects of artificial lighting, such as poor uniform distribution of light and shadow, increase the contrast between the observed object and the background brightness, and cause difficulties for safe operation. In order to make full use of sunlight, we should pay attention to the following points: clean the windows and increase the transparency of glass; Expand the area of the window or set the window at a higher position; Where workers or machines are placed, choose places that can absorb more sunlight as much as possible; Install a skylight made of translucent material on the ceiling of the workshop. Third, the walls and ceilings of the workplace adopt light colors. Different colors have different light reflectivity, while white has the highest reflectivity for light, which can reach more than 90%. Therefore, absorbing the same intensity of light, rooms decorated with white or light tones can achieve brighter lighting effect. Moreover, because white has the psychological effect of refreshing and relaxing, white walls and ceilings can make the room more comfortable and pleasant, and help to improve the work efficiency of workers. In order to achieve the effect of uniform distribution of light in the workshop, the great contrast between the brightness of the wall and the ceiling should be avoided. It is best to decorate the ceiling with white, and the wall should be light-colored, and it is not advisable to use shiny and dazzling paint or decorative materials to avoid reflection glare. In addition, the lighting device should adopt the upper opening design, which can not only illuminate the ceiling, but also cause more uniform light distribution and less dust accumulation. Fourth, it is difficult to provide adequate lighting in places where people are often active and it is impossible to get light. In practice, people tend to overlook the lighting needs of corridors, passages, staircases, warehouses and other places that cannot be directly reached by sunlight. Although the lighting requirements of these places can be lower than those of production workshops, sufficient lighting should be maintained to ensure the safe walking of personnel and the transportation of goods. In workplaces with weak light and different heights, surfaces with different heights should be marked with different colors, so that the height differences can be clearly seen. In dangerous workplaces, obstacles that hinder the normal distribution of light should be removed to eliminate all shadows that may cause accidents. Because it takes some time for vision to adapt to the new environment from dark to bright, the change of illumination brightness from corridors, corridors, staircases, warehouses to workshops should be minimized in the layout of artificial light sources. 5. Provide local lighting for jobs requiring high intensity lighting. Jobs engaged in precision work or inspection work need more illumination than ordinary production or office work. Installing local lighting in these workplaces can greatly improve the efficiency and safety of precision work. The following issues should be paid attention to when setting local lighting: 1. The local lighting source should be equipped with a deep lampshade or crotch light plate, and the inner side of the lampshade and the light blocking plate should be painted with dull color to avoid strong direct glare and reflection glare; 2. For jobs requiring color recognition, fluorescent lamps should be used for local lighting; 3. The illuminance of local lighting, in addition to the precision of the work itself, should also consider the age of workers. The older the age, the greater the illuminance required. For example, 60-year-old workers need more than five times more illumination than 20-year-old workers to see a printed tax form comfortably; 4. For jobs that require high visual speed (that is, the time required to see objects clearly is short), such as inspecting tiny defects of products on the assembly line, the required illumination is also higher than that of ordinary jobs; 5. Local lighting and general lighting should be combined so that the contrast of light between workbench, working point and background is not too large.