Not needed, open check, the dampers being closed; when.
EL 75.3m (247 FT) — EL 14.3m (47 FT) -— EL 8.2m (27 FT) — ELO PAD SURFACE BOTTOM OF FLAME TRENCH PA HYDROGEN Z i AN EL 50.9m (167 FT.
EL 75.3m (247 FT) — EL 14.3m (47 FT) -— EL 8.2m (27 FT) — ELO PAD SURFACE BOTTOM OF FLAME TRENCH PA HYDROGEN Z i AN EL 50.9m (167 FT.