How to deal with the noise of laboratory fume hoods and fume hoods

The fume hood is an indispensable exhaust equipment in the laboratory Reasonable installation can effectively reduce the harm of the laboratory staff from the chemical gas I have been to many laboratories Some laboratories have either a big smell or too much noise The smell is that the exhaust is not well handled There are many reasons for the noise Here is how to solve the problem of the noisy fume hood in the laboratory Problem If a laboratory is equipped with multiple ventilators * a good way is to use a set of exhaust system, that is to say, install outdoor centrifugal fans If each fan is installed separately, open all the ventilators when doing the experiment and all the fans are working at the same time It's a bit intolerable to make a buzzing noise So we can only install outdoor centrifugal fans Outdoor centrifugal fan 1 Generally installed on the roof, what if the top floor is an experimental building or an office building? Is there no noise when the outdoor centrifugal fan is installed on the roof? The answer is very simple There must be noise from centrifugal fans, which is even louder than that from indoor axial-flow fans How to deal with it? Let me introduce some methods to deal with the noise 1 The device is made of a kind of porous silencing material, which is fixed on the inner wall of the airflow passage to achieve the purpose of silencing 2 Shockproof pad: when installing the fan, the shockproof pad under the fan can effectively reduce the noise 3 The thickness of the exhaust pipe can also affect the ventilation noise The ventilation pipe should be as thick as possible The thick pipe can not only reduce the noise, but also the ventilation effect is much better than that of the thin pipe Generally, the pipe with diameter of 350 or 400 is suitable 4 Frequency conversion system, if conditions permit * install frequency conversion system, frequency conversion system means that if the laboratory has installed four fume hoods, if I only start two fume hoods, then the noise is only one-half of the four at the same time, if I only start one fume hood, then its noise is only one-quarter of the total start-up Therefore, if the laboratory fume hood is installed well, as long as attention is paid to the details of all aspects, the equipment can achieve the best effect.