Taga tuubada birta ah waxay ka samaysan tahay kaarboonka ama tuubbada birta ee aleorta, taarikada, astaamaha, qaab gaar ah oo shaqeyn kara cabitaannada (ka beddel jihada dareeraha ama nidaamka) nidaamyada dhuumaha. Badanaa rakibadahan waxaa ka mid ah suxulka birta (45 ama 90 digrii xasaasi ah), tigo, sicir-barar (sicir-barar (caleenta, ibta, naaska, gasket, gascadaha iyo iwm.