1) local ventilation

利用局部的送、排風控制室內局部地區的污染物的傳播或控制局部地區的污染物的傳播或控制局部地區的污染物濃度達到衛生標準要求的通風叫做局部通風。局部通風又分為局部排風和局部送風。

Ventilation is called local ventilation by using local air supply and exhaust air to control the spread of pollutants in local areas or to control the spread of pollutants in local areas or to control the concentration of pollutants in local areas to meet the requirements of health standards. Local ventilation is also divided into local exhaust and partial air supply.

①局部排風

Local exhaust air

局部排風是在集中所產生有害物的局部地點，設置有害物捕集裝置，將有害物質就地排走，以控制有害物質向室內擴散。局部排風系統如圖2-2所示。

Local air exhaust is a local place where harmful substances are produced in a centralized way, and a harmful collection device is set up to remove harmful substances in place to control the diffusion of harmful substances into the room. The local exhaust system is shown in Figure 2-2.

②局部送風

Local air supply

局部送風方式是利用通風機和風管，直接將室外新鮮空氣或者經過處理后具有一定參數的空氣送到工作地點。煉鋼、銹造等高溫車間經常采用這種通風方式。

The local air supply mode is to directly send outdoor fresh air or air with certain parameters to the working place by fan and air duct. This way of ventilation is often used in high temperature workshop such as steelmaking and rust making.

2） 通風

2) comprehensive ventilation

通風是對整個房間進行通風換氣。通風包括排風，送風和送、排風。

Ventilation is the ventilation of the whole room. Comprehensive ventilation includes comprehensive exhaust, full air supply and full delivery and exhaust.

①排風

Overall exhaust ventilation

排風是從整個房間排除有害物質的通風方式，為了使室內產生的有害物盡可能不擴散到其它區域或領室去，可以在有害物比較集中產生的區域或房間采用機械排風。圖2-4位機械排風系統，圖2-4（a）是在墻上裝有軸流風機的簡單排風系統。

Comprehensive ventilation is the ventilation method of eliminating harmful substances from the whole room. In order to make the harmful substances produced indoors do not spread to other areas or leading rooms as far as possible, a comprehensive mechanical exhaust air can be adopted in the areas or rooms that are produced in a relatively concentrated area. Figure 2-4, a comprehensive mechanical exhaust system. Figure 2-4 (a) is the simplest comprehensive exhaust system equipped with axial fans on the wall.

②送風

Overall air supply

把符合衛生要求的空氣送到整個房間各個部位的送風系統稱為送風。可以通過自然通風和機械通風來實現。機械送風系統如圖2-5所示，經過處理后的空氣，在風機的作用下，經風管、送風口送入整個房間的各個部位，而排風可通過排風口或門窗排出。

The air supply system that accords with the hygienic requirements to the whole room is called the full air supply. It can be achieved through natural ventilation and mechanical ventilation. The overall mechanical air supply system, as shown in Figure 2-5, shows that the treated air is sent to all parts of the whole room by the wind pipe and air outlet under the action of the fan, and the exhaust air can be discharged through the exhaust vent or door and window.

③送、排風

Overall delivery and exhaust

在門窗緊閉，自然排風或進風比較困難的房間，常采用圖2-4所示排風和圖2-5所示的送風相結合的送、排風系統。

In a room with closed doors and windows, a room with a natural exhaust or a difficult entry, a comprehensive air supply and exhaust system combined with the overall air supply shown in Figure 2-5 is often used in Figure 2-4.