E
SECTION E — FIXED CONSTRUCTIONS
  
BUILDING
 E21
MINING
 E21B
DEEP DRILLING; OBTAINING OIL, GAS, WATER OR SOLUBLE MATERIALS FROM DEEP WELLS

 E21C
MACHINERY FOR, OR METHODS OF, MINING OR QUARRYING

 E21D
SHAFTS; SINKING SHAFTS; GALLERIES; LINING GALLERIES

 E21F
VENTILATION; SAFETY DEVICES; TRANSPORT; FILLING UP; RESCUE