Dry cleaning originated in Europe, and different dry cleaning agents such as gasoline, carbon tetrachloride, trichloroethylene, trichlorotrifluoroethane, etc. have also been tried before. The longest used is the dry-cleaning agent, tetrachloroethylene, which has grown up to 70-80 years so far in many developed countries in Europe, Australia and North America.
Tetrachloroethylene washing equipment still occupies more than 80% of the share. Because tetrachloroethylene is slightly toxic, long-term exposure to tetrachloroethylene is harmful to health. Although there is no limit on the concentration of tetrachloroethylene in domestic environmental protection, the design and use of washing equipment should be considered as far as possible. Avoid or reduce exposure to tetrachloroethylene. Therefore, many countries in the world have made relevant regulations on the permissible concentration of tetrachloroethylene gas in the working environment. Its allowable range is between 25PPM-50PPM. China stipulates that it is 200 mg / m3 (ie 27PPM, GB16204-1996). This is a stricter standard in line with developed countries in the world.
As we all know, alcohol is also a toxic solvent. The amount of alcohol consumed by humans per day is calculated in 10,000 units, but not many people are poisoned by drinking alcohol-containing poisonous solvents, mainly because of the degree of control, which does not exceed the standard for humans to accept poisoning, so it will not be poisoned. Therefore, controlling the emissions of tetrachloroethylene and human intake is the key to ensuring safety.
For the open-type washing equipment, its structure must have exhaust gas. In order to ensure that the operators of dry cleaning franchise stores, the loading and unloading of clothing and clothing should be under negative pressure to prevent the tetrachloroethylene gas from overflowing from the loading port. The standard for washing equipment also made clear: "Opening washing equipment should have a safety interlock device. The loading door is not closed and the machine cannot be started; when the loading door is opened, the fan should be started automatically; when the loading door is closed, The fan stops automatically. " For fully enclosed water washing equipment, because there is no air extraction when the door is opened, the operator can still smell the odor and still cannot eliminate the harm. Therefore, new water washing equipment has been improved, and different manufacturers have adopted different measures. There are also some manufacturers' washing equipment with interlocks that cannot open the charging door during the start-up operation to avoid accidental injury caused by misoperation.
The noise of washing equipment is generally far lower than the environmental protection limit. The standard stipulates that it is not greater than 80dB (A). How to reduce noise is not only a design and manufacturing problem, but also largely limited by the quality of supporting parts. For large washing equipment Noise control can't be ignored. In order to prevent accidental mechanical injury, the standard stipulates that "a rigid protective cover should be added to the rotating belt and shaft, etc." This is a common sense of design, but it is necessary to emphasize it. Especially after repairing the machine, the user must install the protective cover. The requirements for the protective cover are not only rigid, but also care must be taken to ensure that it is not possible to accidentally insert your fingers.
In general, when using dry cleaning equipment in tetrachloroethylene, it is best to choose a fully-closed type, and try to avoid dry cleaning of intimates, sheets, quilts, etc. If you have dry cleaning clothes that are needed for dry cleaning, you find that there are heavy The pungent odor may be caused by a large amount of tetrachloroethylene remaining on the clothes. Because tetrachloroethylene is a highly volatile substance, consumers can hang the clothes in a ventilated place for a while to dry when they retrieve their clothes from the dry cleaners, and wait until the tetrachloroethylene has evaporated. In order to ensure that tetrachloroethylene does not play a role in mutual poisons, it will not bring adverse safety risks to people's health.