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The chemical laboratory is a space with a certain degree of danger, and experimental operations use practical products such as acids, bases, and organic solvents; Glassware such as test tubes, flasks, beakers, condenser tubes, precision instruments such as atomic absorption, gas chromatography, liquid chromatography, ultraviolet spectrophotometer, as well as high-temperature equipment such as ovens and muffles.

The chemical laboratory is engaged in research and experiments, including the mixing, heating, cooling, distillation, evaporation, dilution and reaction of chemicals. These works can be operated on an open laboratory bench or fume hood. The required analytical equipment such as spectrophotometer, gas, liquid layer analysis, etc. The Analytical chemistry laboratory often uses some harmful substances, including highly toxic, volatile liquids, powders, and pressurized combustible gases. Although toxic substances can be decomposed into non-toxic compounds in the analysis process, they are still toxic in the analysis operation, and it is generally not recommended that Analytical chemistry laboratories operate extremely toxic chemicals, such as carcinogenic, deadly and explosive chemicals and higher radioactive substances.

The laboratory rooms are roughly divided into three categories: precision instrument rooms, chemical analysis laboratories, and auxiliary rooms (offices, storage rooms, and cylinder rooms)

1) The precision instrument room is required to have functions such as fire prevention, shock resistance, electromagnetic interference prevention, noise prevention, moisture prevention, corrosion prevention, and prevention of harmful gas invasion, and the room temperature should be kept as constant as possible. To maintain the good performance of general instruments, the temperature should be between 15-30 ℃,. The instrument room with a humidity of 60% -70% and a constant temperature can be equipped with double doors, windows, and air conditioning devices.

Terrazzo or anti-static floor can be used in the instrument room. Carpet is not recommended because it is easy to accumulate dust and generate static electricity. The power supply voltage of large precision instrument room is stable. Generally, the allowable voltage fluctuation range is ± 10%. If necessary, auxiliary equipment (such as a regulated power supply) should be equipped. To ensure uninterrupted power supply, dual power supply can be used. A dedicated grounding wire should be designed with a grounding electrode resistance less than 4 Ω.

The gas chromatography room and atomic absorption analysis room should be located near the visible cylinder room (facing north) due to the need for high-pressure steel cylinders. The experimental platform used for placing the instrument is located at a strong distance of 500mm for easy operation and maintenance. There is good ventilation indoors, and a local exhaust hood is installed above the atomic absorption instrument.

Microcomputers and precision instruments controlled by microcomputers have certain requirements for power supply voltage and frequency. To prevent voltage transients, momentary power outages, insufficient voltage, and other factors from affecting instrument operation, an uninterruptible power supply (UPS) can be selected as needed.

2) The chemical analysis room conducts chemical treatment and analysis of samples. During work, small electrical equipment and various chemical reagents are often used, which can pose certain risks if not handled carefully. In response to these usage characteristics, the following requirements should be noted in the design of the chemical laboratory:
(1) Architectural requirements: The building of the laboratory should be fire-resistant or constructed with non flammable materials, and the partition and ceiling should also consider fire performance. Terrazzo floor can be used. The windows should be dust-proof and the indoor lighting should be good. The door should be opened outwards. The laboratory should be equipped with two exits to facilitate the evacuation of personnel in case of accidents.
(2) Water supply and drainage: Water supply should ensure the necessary water pressure, quality, and quantity to meet the needs of normal operation of instruments and equipment. The indoor main valve should be located in a prominent position that is easy to operate. The sewer should be made of acid and alkali resistant materials, and the ground should have a floor drain.
(3) Ventilation facilities: since toxic or flammable gases are often produced in the laboratory work, the laboratory should have good ventilation conditions. There are generally three types of ventilation facilities: ① Whole-house fan or ventilation shaft is used for the whole room ventilation, and the Air changes per hour is generally 5/h. ② The local exhaust hood is generally installed above the area where harmful gases occur in large instruments. Install a local exhaust hood above the area where harmful gases are generated in teaching experiments to reduce indoor air pollution Fume hood
(4) Gas and power supply: Conditional laboratories can install pipeline gas. The power supply, lighting, and equipment of the laboratory use electricity. Fluorescent lamps should be used for lighting. In equipment electricity usage, electrical appliances that operate for 24 hours, such as refrigerators, are powered separately, while other electrical equipment is controlled by a main switch. Electric heating equipment such as ovens and high-temperature furnaces should have dedicated sockets, switches, and fuses. Install emergency lights indoors and in corridors for use in case of sudden power outages at night.
(5) Laboratory: It mainly consists of a table top, a bracket under the table, and a container cabinet. For ease of operation, sample racks can be installed on the table, and sinks can be installed at both ends of the table. The table top is generally 750mm or 1500mm wide, with a length of 1500-3000mm depending on the room size, and 800-850mm for advanced technology. The countertop is commonly made of veneer physicochemical boards, solid core physicochemical boards, epoxy resin boards, Qiansi boards, ceramic boards, etc. The ideal countertop should be flat, not easily broken, resistant to acid, alkali, and solvent corrosion, heat-resistant, and not easy to break glassware, etc.
3) Auxiliary room
(1) Sample storage room: As many chemical reagents are flammable, explosive, toxic, or corrosive, do not purchase too many. The storage room is only used to store a small amount of chemicals that need to be used in the near future, and must comply with the safety requirements for storing dangerous goods. It should have the functions of preventing open flames, moisture, high temperatures, direct sunlight, and lightning. The drug storage room should face north, dry and well ventilated. The ceiling should be shaded and insulated. The doors and windows should be solid. The windows should be high windows. The doors and windows should be equipped with Sun visor. The doors should open outward. The Flammable liquid storage room should generally not exceed 28 ℃, and explosives should not exceed 30 ℃. A small amount of dangerous goods can be stored separately in iron or cement cabinets. The room is equipped with exhaust cooling fans, explosion-proof lighting fixtures and fire-fighting equipment. The Semi-basement that can meet the above conditions is the sample storage room.
(2) Cylinder room: Flammable or combustion supporting gas cylinders are required to be placed indoors. The cylinder room is required to be far away from heat sources, ignition sources, and flammable material warehouses. The cylinder room should be constructed of non combustible or non combustible materials, with explosion-proof walls and a lightweight top cover. The door should be opened outward to avoid direct sunlight and have good ventilation conditions. The cylinder should be located at least 10m away from the open flame heat source, and there should be an upright and stable iron frame inside the room for placing the cylinder.