DIN 21633:2011-03 Air regulating systems for mining - Wing air doors for haulage tracks - Double-wing type doors without pressure reduction / Note: DIN 21633 (1993-10) remains valid alongside this standard until 2011-08-31.
2011DIN 21633:2011-03 Air regulating systems for mining - Wing air doors for haulage tracks - Double-wing type doors without pressure reduction / Note: DIN 21633 (1993-10) remains valid alongside this standard until 2011-08-31.
2011DIN 21633:2011 Air regulating systems for mining - Wing air doors for haulage tracks - Double-wing type doors without pressure reduction
1993DIN 21633:1993 Air regulating systems in mining; wing air doors for haulage tracks; double-wing type doors without pressure reduction