It usually depends on the situation. We usually excuse ourselves and tell the fellow by whispering to them to please lower it down as we are being disturbed. we usually say, mawalang galang na po, puede po ba tayong tumahimik dahil nakakagambala po tayo, this is in Pilipino, In tagalog street language, we say sir, medyo maging tahimik po tayo kasi may ______ (natutulog, nagmemeeting, or etc). The Pilipino version is very formal and classical which means please excuse my intrusiveness but may we please lower it down because we are causing a stir up, while the tagalog version is the colloquial version which means, Sir, kindly lower it down because there is _____________ someone sleeping or there is a meeting going on.

You can say "tahimik!" (quiet!) if you're in a good mood to shout. Walang maingay roughly translated as (wala=none) and (maingay=noisy) if you are calmly asking everyone to be silent. If you are asking someone to shut up, you can use manahimik ka or tumahimik ka (you be quiet!). If you are asking more than one person to be quiet, you use huwag (don't) kayong (referring to more than 1 person) maingay (noisy)..annyeong.

It is ..."Walang maingay"... or if you want you may also say.. "Shhhhhh" hahaha

the standard translation to Tagalog of "be quiet" is "walang iimik" or "walang kikibo" or simply, "walang maingay" if it implies to telling someone to shut up or to stop talking about something (a secret perhaps). :)

You could just simply say "tahimik".