Mobile Public Toilet Exhaust

The exhaust situation of mobile public toilets is as follows:

Exhaust Fan Noise

The noise of the exhaust fans in outdoor mobile public toilets is reasonably controlled and meets the noise standards for outdoor public facilities. The selected exhaust fans are all low-noise specialized ones with low power and moderate rotational speed. When operating, the noise is generally between 30 - 50 decibels, equivalent to the sound of normal conversation. The noise is soft and does not produce harsh abnormal sounds, so users in the toilet stalls are hardly disturbed by the noise. When installing the exhaust fans, shock-absorbing pads are provided to reduce the vibration noise generated during operation. Meanwhile, the insulation and sealing layers on the walls and roofs of the public toilets also play a certain soundproofing role, reducing noise propagation. During daily use, if the noise of the exhaust fan suddenly increases, it may be due to excessive dust accumulation on the fan blades, loose bearings, or equipment failures. After timely cleaning and maintenance, the noise can return to normal.

Exhaust Process and Effects

• Forced Exhaust and Negative Pressure Toilet: By installing equipment such as exhaust fans, the foul air in the toilet is directly discharged outdoors, while creating a negative pressure state inside the toilet bowl. The advantages are low cost and simple structure, which can improve the air circulation in the toilet to a certain extent and reduce the accumulation of odors. The disadvantages are that it does not meet current environmental protection requirements, has poor deodorization effects, and the direct discharge of foul air from the toilet into the atmosphere can pollute the air and affect surrounding residents. The negative pressure state inside the toilet bowl can cause uncertain air to enter the toilet from the outside, resulting in secondary pollution, and toilet users will be the first to be infected by the dirty air inside.
• Centralized Collection, Purification, and Direct Discharge into the Atmosphere: Pipes are used to centrally collect the foul odors from the toilet bowls, which are then purified and discharged into the atmosphere. The advantage is that after one purification, the toilet odor can be eliminated, improving the air quality inside the toilet to a certain extent. The disadvantage is that if the toilet has a strong odor, one purification may not completely remove the odor. Even if discharged outdoors, the area around the toilet will still be polluted. Due to the severe negative pressure inside the toilet bowl, the polluted air from the outside directly enters the toilet, causing secondary pollution, and users inside the toilet will be the first to be infected by the dirty air in the toilet.
• Air Circulation System: An airflow barrier is formed between the user room and the equipment compartment through a negative pressure gradient. Fresh air enters from the top grille, passes through an activated carbon and photocatalytic composite filter, and then flows vertically downward at a rate of 0.3 meters per second. The aerosol particles generated during use are guided by the descending airflow into the bottom collection device, avoiding cross-contamination in the space. The exhaust pipe is equipped with a built-in plasma cluster generator, which can decompose organic odor molecules into carbon dioxide and water vapor.