Requirements for laboratory ventilation

 The laboratory ventilation system is one of the most important systems in the entire laboratory construction.
Its effect will directly affect the laboratory environment and the physical health of the experimenters
.

The editor of PATEO will show you the requirements for laboratory ventilation
.

 1.
Specify the design parameters of laboratory air conditioning and ventilation: 1.
Air quality; 2.
Room pressure difference; 3.
Inlet and supplementary air; 4.
Control and alarm; 5.
Minimum number of air changes; 6.
Type of exhaust equipment; 7.
Backup of equipment and power supply; 8.
Indoor and outdoor temperature and humidity requirements; 9.
Anticipated increase in internal load; 10.
Possible adjustment of size and number of fume hoods; 11.
Equipment and process heat load, including sensible and latent heat
.

 Second, the choice of ventilation times Under normal circumstances > 10 times / hour of room ventilation times is considered appropriate
.

However, when there are analytical equipment in the laboratory that may generate a high heat load, or when there is a large amount of local exhaust air in the room, the ventilation rate may need to be increased accordingly
.

The wet chemical room has fume hoods and the heating room has a large number of furnaces
.

The calculation method of the fume hood refers to the light, moderate or dangerous hazardous substances in the "Chemical Heating Ventilation and Air Conditioning Regulation Design Specification".
When the indoor ceiling has supplementary air, the minimum suction surface of the operation port of the fume hood Speed ​​0.
5m/s
.

 3.
Air supply and exhaust form All exhaust devices in the same laboratory should share one exhaust system
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The laboratory that uses the exhaust system continuously during working hours should set up an air supply system, and the air supply volume should be 70% of the exhaust air volume, and the air supply should be air-purified according to the process requirements
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For heating areas, the supply air should be heated in winter
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Supply air flow should not disrupt the normal operation of the laboratory exhaust
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 Fourth, the room pressure difference constant temperature and humidity room needs strict temperature and humidity control range, and should be designed as positive pressure
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Because if it is designed to be negative pressure, the air in the adjacent area will enter, on the one hand, it may destroy the control of temperature and humidity; on the other hand, if the polluted air enters, it may also cause safety problems
.

For wet chemical rooms and heating rooms, it is necessary to design negative pressure in order to prevent toxic, corrosive, high-temperature gases or volatiles from being emitted into the room, or even to other areas
.

 5.
Control system control The above items should be integrated to meet the room pressure, pressure difference of each room, ventilation volume, temperature and humidity and various safety control requirements of the entire laboratory, and at the same time reduce energy consumption
.

There are often many chemical pollution sources that are not conducive to human health in the laboratory, especially harmful gases.
It is very important to exclude them
.

But at the same time, energy is often consumed in large quantities, so the requirements of laboratory ventilation control systems have changed from early constant air volume, bistable, variable air volume systems, to new adaptive control systems
.