Laboratory ventilation system is one of the largest and most influential systems in the whole laboratory design and construction process. Whether the ventilation system is perfect or not directly affects the laboratory environment, the health of the experimenters, and the operation and maintenance of the experimental equipment.            Laboratory excessive negative pressure, fume hood gas leakage, laboratory noise and other issues, has been puzzling laboratory workers. These problems have caused serious physical and psychological harm to people who work in the laboratory for a long time, and even to the management and logistics personnel working around the laboratory.            A scientific and reasonable ventilation system requires good ventilation, low noise, easy operation, energy saving, and even indoor pressure and temperature and humidity can maintain the comfort of the human body.            1. Design standards            1, code for design of heating, ventilation and air conditioning (GBJ19-87-2003).            2. Standards for quality inspection and assessment of ventilation and air conditioning engineering (GBJ304-2002).            3. Concise ventilation design manual (GB50194-2002).            4. Code for construction and acceptance of compressor, fan and pump installation engineering (JBJ29-2002).            5. Specification for construction and acceptance of low voltage electrical installations for installation of electrical installations (GB50254-96)            6. Comprehensive emission standard for atmospheric pollutants (GB16297-1996).            7, ambient air quality standard (GB3095-1996).            8, urban ambient noise standard (GB3096-93).            9. Code for fire protection design of buildings (GB50016-2006).            10, "energy efficiency design standards for public buildings" (GB50189-2005).            11, the company's relevant information and relevant information provided by Party A.            Two. Design principles            1. According to the structure characteristics of the building, the wind well is opened near the building to divide the exhaust air and the air supply system. The pipe system is "short, flat, smooth and straight", reducing the system resistance and reducing the noise of the system.            2, the air exhaust and air supply system can achieve the balance of air volume, maintain the negative pressure of indoor -5Pa -10Pa, prevent the overflow of harmful gases, and ensure the physical and mental health of the experimenters.            3, summer cold wind, winter warm air to ensure indoor temperature and humidity comfort;            4, intelligent frequency conversion control system is adopted to achieve the purpose of convenient operation, energy saving and noise reduction.            5. Considering various factors, we should adopt mature technology with less investment, stable operation, low operation cost and good operation effect.            6, the selected process must meet the site conditions, the layout is concise, compact, less occupied, and convenient for production operation and maintenance.            7, non-standard equipment should conform to the relevant specifications of the state or industry, and ensure stable performance and beautiful appearance.            8, in the design, we should give full consideration to noise and odour, so as to prevent the occurrence of the two pollution and not cause new pollution to the surrounding environment.