Abstract: The present invention is a push-pull ventilation hood having a push device to obtain a push air flow and a pull device to exhaust contaminant flow with an exhaust opening and the two devices properly coordinated with each other, wherein, when the push flow flows through a contaminant source, a contaminated flow of the push flow is exhausted through the exhaust opening. Based on the design process according to the present invention, a push-pull hood with the highest efficiency of push velocity can be designed and the push-pull hood can economically and effectively control the contaminant source.

Abstract: A biological safety cabinet (BSC) has an air curtain to isolate air inside and outside the BSC. A most preferable slight concave curtain of air can be obtained. With the curtain, neither contamination in the BSC leaks out nor outside contamination enters the BSC. Furthermore, no circulation is formed in the BSC by blowing the air curtain. Thus, the operator using the BSC and the product in the BSC are both well protected.

Abstract: The present invention is a fume hood capable of exhausting contaminant, having an air pipe in a sash and a suction slot corresponding to the air pipe deposed at the front rim of the bottom surface to obtain an air curtain, where contaminant is efficiently prevented from leakage and energy is saved.

Abstract: The present invention is a fume hood capable of exhausting contaminant, having an air pipe in a sash and a suction slot corresponding to the air pipe deposed at the front rim of the bottom surface to obtain an air curtain, where contaminant is efficiently prevented from leakage and energy is saved.

Abstract: The present invention is a fume hood with a mechanism of air suction together with air supply to save energy while locally exhausting pernicious gases near a contaminant source.

Abstract: The present invention is a push-pull ventilation hood having a push device to obtain a push air flow and a pull device to exhaust contaminant flow with an exhaust opening and the two devices properly coordinated with each other, wherein, when the push flow flows through a contaminant source, a contaminated flow of the push flow is exhausted through the exhaust opening. Based on the design process according to the present invention, a push-pull hood with the highest efficiency of push velocity can be designed and the push-pull hood can economically and effectively control the contaminant source.

Abstract: The present invention discloses an airflow capture booth with single-plate windbreak comprising an extracting means for extracting polluted air having an opening for air contamination extracting through and a crosswind device for simulating crosswind, the improvement comprises that said crosswind device having a single-plate windbreak perpendicular to an airflow direction of said crosswind having a specific distance to said opening of said extracting means for forming a capture zone, wherein the airflow of said capture zone is not easy to be shed and is extracted mostly by said extracting means.

Abstract: The present invention discloses an airflow capture booth with single-plate windbreak comprising an extracting means for extracting polluted air having an opening for air contamination extracting through and a crosswind device for simulating crosswind, the improvement comprises that said crosswind device having a single-plate windbreak perpendicular to an airflow direction of said crosswind having a specific distance to said opening of said extracting means for forming a capture zone, wherein the airflow of said capture zone is not easy to be shed and is extracted mostly by said extracting means.