Reason For Hijab Exclusion
Bismillah-hir-Rahman-nir-Raheem
Assalamu-`alaykum wa rahamatullahi wa barakatuhu
Women past child-bearing can remove outer garment.Provided adornment[jewellery,decoration etc is not seen].
24:60 And as for women past child-bearing who do not expect wedlock, it is no sin on them if they discard their (outer) clothing in such a way as not to show their adornment. But to refrain (i.e . not to discard their outer clothing) is better for them. And Allah is All-Hearer, All-Knower.[
*Note:they'll have to wear khimaa which should cover face and bosom.But wearing jilbab is much better.]
Allah knows best.