Rav Yoni Rosensweig wrote these Halachot for the 9 Days:
The following is a short list of Piskei Halacha, without explaining much behind the psak. Please feel free to contact me for further explanation.
– Going to work during the Nine Days is allowed according to the majority of opinions, and this is the minhag as well. Some allow all business, some allow only what one does to make a living, and some allow only that which is not associated with joyful actions, such as weddings, etc. The minhag is to go by the first opinion, but whatever one can do to reduce his business-related actions is best. Any business that is mitzvah-related or for the needs of the community is allowed.
– The gemara advises against engaging in any activity which might be dangerous or hazardous during the Nine Days. As a result, some refrain from flying, travelling and going to the beach. In truth, these actions are permissible during the Nine Days (if not done for pleasure but for work or for exercise), but where not necessary it is better to refrain.
– Engagements are allowed during the nine days. Engagement parties are not. Weddings should not be done, but if for some reason there is a need they can be had during the Nine Days.
– Events, gatherings, meetings, conventions and conferences – may be attended, so long as they are not of a festive nature.
– Dancing and music is not allowed during the Nine Days. Some allow Acapella music (I personally do not).
– Our minhag is to treat Shabbos during the Nine Days like any other Shabbos.
– Some say one cannot do laundry, nor wear laundered clothes, during the Nine Days (and for Sephardim from the beginning of the week that Tisha B’av falls on – Shavua Shechal Bo). Some say that both are permitted for everyday clothes (not Shabbos clothes). And some say that laundered clothes are allowed, but doing laundry is not (and this is my opinion). Even the most stringent allow the washing and wearing of tablecloths, towels, socks, underwear, and small children’s clothes, if one runs out of them. Laundry for Shabbat is also permitted if needed.
– Shaving and haircuts are prohibited during the Nine Days, (and for Sephardim from Shavua Shechal Bo). Cutting nails is permissible.
– Buying and fixing things during the Nine Days is prohibited, unless it’s an opportunity that won’t be available later.
– We do not say Kiddush Levana during the Nine Days. Right after the fast one should not say it either until he has drunk something (other than water).
– Wine and meat should not be consumed during the Nine Days (and for Sephardim from Shavua Shechal Bo). Chicken, and things cooked with meat, are included. Small children, weak adults, pregnant or nursing women, may all have meat if they have a need for it. The wine of the havdallah can be drunk by an adult, but if a child is available he should have it. One can eat meat on Shabbos or at a Siyum.
– Washing oneself for hygiene is permissible.
– One should refrain from saying Shehecheyanu during the Nine Days.
– Seuda Mafseket should be relatively sparse, with only one cooked food allowed, no meat and no wine. Many people have a proper meal after Mincha and then at the end of it eat an egg on the side as the Seuda Mafseket. It seems from the Shulchan Aruch that this practice is erroneous. At the very least, one should break between the large meal and the Seuda Mafseket with Mincha. My personal minhag is to eat a proper meal 3-4 hours before the fast, and then have a Seuda Mafseket after mincha with bread and an egg and fruit and vegetables. When Tisha B’av comes out on Motzei Shabbos (like this year) it is permissible to eat as much as one desires in the Seuda Mafseket.
– One may decide to continue eating or drinking even after the Seuda Mafseket is over.
– On the eve of the fast one may learn whatever Torah they want (and not only the things permissible on Tisha B’av).
– The fast starts from sundown and ends with nightfall. Marital relations, showering, lathering with oil, eating, drinking, and wearing leather shoes are prohibited.
– Washing one’s hands for davening or in order to clean them is permitted, but if possible one should only wash the fingers and not the whole hand.
– One may only learn things which involve sadness and destruction, such as: Eichah, Job, the negative parts in Yirmiyahu, Third perek of Moed Katan, Halachos of Aveilut, etc.
– Sick people must not fast on Tisha B’av.
– Greeting each other on Tisha B’av is prohibited. If someone greets you, you may acknowledge him slightly but do not give a full greeting back.
– One should stay at home and not enjoy leisurely walks on Tisha B’av. One should sit on the floor on Tisha B’av and act as though he is distant from Hashem.
– It is improper to do business on Tisha B’av, but if one must he should wait at least until after midday. After midday we allow to sit on chairs, as well.
– Tzitzit, Talit and Tefillin are not worn until midday Tisha B’av.
Fasting on Tisha B’av for pregnant /nursing women:
(1) For the purposes Tisha b’av, we will define a pregnant woman as a woman who the pregnancy takes a toll on her. This is true for any woman from the third month on, and includes women who even previous to that point are feeling physically weak, feel a significant need to eat, or that the doctor says they must eat.
(2) For the purposes of Tisha B’av, a nursing mother is a woman who is nursing full-time, or even if a significant amount of the baby’s nourishment still comes from her. The rule is this: if it is important that the mother’s milk not stop, then she should not fast. If, on the other hand, the baby is basically weaned off the milk already, this is not a reason not to fast.
(3) In accordance with the above-mentioned definitions, pregnant and nursing women do not have to fast on Tisha B’av.
(4) If one has a doubt whether they fall into the above categories, they should be lenient, as these fasts are only Rabbinic.
(5) When one eats or drinks, they should eat as much as they need to, and don’t need to worry about it. They should worry more about their health and the baby’s health. Still, on Tisha B’av it is proper not to eat to excess.