1) Tsau hluav taws- qhov rais tiv taus: Lub qhov hluav taws kub- qhov rais tiv taus yam tsis muaj lub tshuab ua haujlwm.
2) Hluav taws kub ua haujlwm- qhov rais tiv taus: Lub qhov hluav taws kub- qhov rais tiv taus nrog lub sash ua haujlwm thiab nruab nrog lub sash qhib thiab kaw tswj ntaus ntawv.
3) Rwb thaiv tsev hluav taws- qhov rais tiv taus (Class A): Hluav taws kub- qhov rais tiv taus uas ua tau raws li ob qho tib si hluav taws kub tiv thaiv kev ncaj ncees thiab kev rwb thaiv tsev nyob hauv lub sijhawm teev tseg.
4) Tsis yog- rwb thaiv tsev hluav taws- qhov rais tiv taus (Class C): Qhov hluav taws kub- qhov rais tiv taus uas ua tau raws li qhov yuav tsum tau muaj kev tiv thaiv hluav taws tsis pub dhau lub sijhawm.
