With the increasing investment in scientific research and education in China, many research institutions and universities have also carried out laboratory construction. However, due to the continuous development of science and technology, higher requirements have been put forward for the design and construction of the laboratory, especially the design of the ventilation system of the laboratory. Therefore, I would like to give a brief introduction to the ventilation design standard and application of the chemical laboratory.

1、 Overview of Laboratory Ventilation Design

Ventilation in the laboratory means that the harmful gas generated in the laboratory is discharged directly or through evolution into the room, and fresh air is introduced into the laboratory, so as to ensure the air conditions in the laboratory and create a good office environment for the laboratory. The process of exhausting air to the outside is called exhaust air, and the process of introducing outdoor air into the room is called air supply. The laboratory fume hood can be simply understood as a fan and box, which are used for the exhaust of the laboratory gas and the discharge to the atmosphere. Laboratory ventilation can be divided into mechanical ventilation and natural ventilation according to different power. Mechanical ventilation is also called local ventilation and overall ventilation. Local ventilation refers to the activities of ventilation within the scope specified by the laboratory, such as areas where harmful gases are concentrated. Overall ventilation refers to the overall ventilation of the laboratory to ensure the air conditions of the laboratory. Laboratory ventilation equipment generally includes universal exhaust hood, atomic absorption hood, fume hood, etc; The ventilation pipeline system mainly includes waste gas treatment equipment, muffler, air valve, air duct, fan, etc. In a word, laboratory ventilation design is a technology to study and control the influence of harmful substances in laboratory on indoor air.

2、 Laboratory ventilation specifications and indicators

During or after the experiment in the chemical laboratory, various unpleasant, harmful, corrosive and explosive gases will be produced. If these gases are not discharged outside in time, they will pollute the air in the laboratory, causing great harm to the laboratory staff, and some of them will also affect the normal use of equipment in the laboratory. In order to prevent the laboratory staff from inhaling or swallowing harmful gases, they should be treated and purified in time to ensure the air quality in the laboratory. Therefore, in the design process of the laboratory ventilation system, the ventilation shall be carried out in strict accordance with the laboratory ventilation specifications, and attention shall be paid to the control of the ventilation system to improve the anti-corrosion effect. For the building code of hazard classification, the ventilation rate is specified according to the area of cubic meters per square meter per minute, while the ventilation criterion from the laboratory building design standard is based on the total volume of the space expressed as the number of air changes per hour, that is, the number of times to change the entire air volume of the laboratory per hour.

In addition, in terms of the ventilation index of the chemical laboratory, corresponding ventilation standards should be formulated to ensure the feasibility of the ventilation design of the chemical laboratory. And determine the times of ventilation and air supply in the chemical laboratory. For example, set the times of ventilation and air supply in the chemical laboratory at 75 times per hour, increase the times of ventilation in the chemical laboratory, and ensure the air quality in the laboratory. At the same time, according to the scale of different chemical laboratories, different air supply and exhaust times are set, such as schools, enterprises, scientific research institutions, etc. According to the actual situation, and through investigation and research, the ventilation indicators that meet the requirements of their own chemical laboratories should be formulated.