Matter regarding bathing
All women must take a head bath on Ekadasi day.
After three menstruating nights, on the fourth day morning, all women must take a bath including a head bath. Married women must take a bath on the fifth day morning to eradicate anyA theetu. Married women must take a head bath on the morning of both the fourth and fifth days.
On the days when the husband performs Tharpanam, the wife must take a bath. On the days of Ammavasyai, Masa-pirappu, Shraddha, if the husband has to do kainkaryam then the wife must take a head bath on these days.
One must take a bath during Grahana Punya Kalam; Punya Kalam and Suddha Mandala snanam are a must.
Apart from this Sumanagalis and Kanya women can take oil baths on Tuesdays and Fridays. During Thirukkarthigai, Kanu, Karadayan Nonbu, Adi, Thai Fridays are considered special for Mangala snanam.
Don’t s- Head Bath
There are no days that are specifically mentioned for head baths sans oil baths. On days like Ammavasyai, Masa pirappu, Shraddham, Pitru Karya one must never take an oil bath even by mistake. For those women whose in-laws are alive and if they happen to participate in the pitru karyam for assisting the mother-in-law, even when the husband is not performing kainkaryam she can just take a head bath or if happens to do kainkaryam during the rituals for Pitru one must take a head bath but never take oil bath for any reason.