If an impurity happens, there is no need to take a full bath to light up a lamp in the evenings. Scriptures have prescribed different types of baths; there is one type of bath called mantra snanam and which has details that women should follow to perform mantra snanam.
Sumangali women can mix water with turmeric powder and can apply them on the chin, hands, and legs, later they can sprinkle the same water around them and chant “Pundarikakshaya NamaH” and recite 2nd pasuram in 2nd padhigam of Perumal Thirumozhi.
“thODulAmalarmangai thOLiNai thOyindum suDarvALiyAl
nIDumAmaram serradum nirai mEyththadum ivaiyE ninaindu
ADippADi arangavO! Enrazhaikkum toNDarippoDi
ADanAperil, gangai neer kuDaindADum vETkai ennAvadE?”
This is the mantra snanam prescribed for ladies. They can light lamps after performing mantra snanam. When women do not have time to take bath after returning home or if it gets late to return home, this practise of elders can be followed.