Ngokwexabiso eliphezulu le-calorific, izinto ezilahlekileyo kwindlela yokulahleka kobushushu zezi:
1. Ilahleko yobushushu bomsi owomileyo.
2. Ukulahleka kobushushu ngenxa yokubunjwa komswakama kwi-hydrogen kwi-fuel.
3. Ukulahleka kobushushu ngenxa yokufuma kumafutha.
4. Ukulahleka kobushushu ngenxa yokufuma emoyeni.
5. Irhasi yomkhuhlane ilahleko yobushushu enengqondo.
6. Ilahleko yobushushu obungaphelelanga.
7. I-Superposition kunye nokulahleka kobushushu bokuqhuba.
8. Ukulahleka kobushushu bombhobho.
Umahluko phakathi kwexabiso le-calorific ephezulu kunye nexabiso eliphantsi le-calorific lixhomekeke ekubeni ubushushu obufihliweyo bomphunga wamanzi (obubunjwe ngokuchithwa kwamanzi kunye nokutsha kwe-hydrogen) kukhululwa.Oko kukuthi, ukusebenza kakuhle kwe-thermal yeejenereyitha zomphunga ngokusekelwe kwiinkwenkwezi ezinobushushu obuphezulu bungaphantsi.Ngokuqhelekileyo kuchaziwe ukuba amafutha anexabiso eliphantsi le-calorific akhethiweyo, ngenxa yokuba umphunga wamanzi kwigesi ye-flue ayidibanisi kwaye ayikhuphi ubushushu obufihlakeleyo bomphunga ngexesha lokusebenza kwangempela.Nangona kunjalo, xa ubala ilahleko yokukhupha, umphunga wamanzi kwigesi ye-flue awubandakanyi ubushushu obufihliweyo bomphunga.