By - ALPHABOGDOG
Some monastic orders have developed their own sign language and have been using them for centuries.
The idea among those who've taken a vow of silence is to limit *communication* to only what's necessary. Sign language can and is used to keep things quiet, but chatting is not what this is about.
So would (in their opinion) it not be considered breaking the vow if in their mind the speech was necessary? For example, asking for something important (like medical attention or something) or letting somebody know they were in danger.
That's necessary speech, so OK.
"How was your day?" "What are you plans for Recreation Hour?" No.