密封式隔音罩 meaning in Chinese

full enclosure

Some 6 . 5 km of noise barriers , including about 4 . 8 km of vertical barriers ranging from three to seven metres high , about 0 . 8 km of semi - enclosures and about 0 . 9 km of full enclosures ; and associated traffic control and surveillance system , electrical and mechanical , building , drainage , landscaping and geotechnical works
竖设长约6 . 5公里的隔音屏障，包括长约4 . 8公里高三米至七米不等的垂直式隔音屏障长约0 . 8公里的半开放式隔音罩和长约0 . 9公里的密封式隔音罩以及