A hasan hadeeth has the same conditions as Sahih Hadith that is except the comprehensive ability of the narrator might be dhaeefer then that of a sahee hadeeth.
The criteria for authentic Sahih Hadith
1) A continuous
unbroken chain to Rasulullaah sallallahu alaihi wasallam
2) The narrator must
be trustworthy.
3) The comprehensive
ability of the narrator is faultless.
4) The hadeeth is
free from irregularities.
5) The hadeeth is
free from any deficiencies. That is why a hasan hadeeth is not regarded as sahee nor is
it regarded as dhaeef.
There is a form of hasan hadeeth which is actually a dhaeef
hadeeth that has increased in strength due to it being narrated via many
different chains.
Those ahaadeeth which
are dhaeef are categorized as dhaeef, this has varying levels, the lowest of
which is maudhoo-fabricated.
There is no difference In Opinion regarding the
permissibility of citing 'a sahee or hasan hadeeth as proof. This can be used
as proof in any aspect of Deen.