Isetshenziswa ezakhiweni zezimboni nezokuhlalisana, imizila kaloliwe, imizila ehamba ngaphansi, emihubheni yamapayipi, amalambu omgwaqo, amalambu ezwe, amasistimu okusabalalisa amandla kagesi aphansi, anganqamuki amalangabi, amakhebuli angashi kanye namaminerali avikela umlilo ekuxhumekeni kwegatsha okumaphakathi.