Ibhokisi yokulawula okuphazamiseka ngokwezinhlanzi zokugcina izikhathi ziyisisekelo esikhulu sokuthuthukiswa kwemisebenzi yezinhlamvu ezithuthukisiwe, amanzi, umlotha, noma izinhlamvu. Kuyisisekelo esetshenziswa kakhulu ukuze kwenzeke iziguli zokuphazamiseka. Leli bhokisi lokulawula lithengiswa ngezinto zokugcina zezindlela zokusebenza, lisebenzisa ukunakekela nokulawula izinhlelo zezinhlamvu ukuze kuyisisekelo kwenzeke iziguli zokuphazamiseka. Leli bhokisi lokulawula lithengiswa ngezinto zokugcina zezindlela zokusebenza, lisebenzisa ukunakekela nokulawula izinhlelo zezinhlamvu ukuze kuyisisekelo kwenzeke iziguli zokuphazamiseka.