通风空气 meaning in English

vent air

Ventilating air purification system of bulk carrier engine room
散货船机舱通风空气净化系统
Method of testing general ventilation air - cleaning devices for removal efficiency by particle size
通过粒度测试通用通风空气净化设备排除效率的测试方法
Practices for measurement , testing , adjusting and balancing shipboard heating , ventilation , air conditioning and refrigeration systems
测量检验调节和平衡船载加热通风空气调节和制冷系统的实施规程