@Jeruba @Bellatrix when I was in the seminary, as mentioned above, we had certain periods of silence, for the purpose of promoting things like meditation, contemplation, silent prayer, introspection, etc. Except for the vow part, it seems to me that this was similar. We weren’t required to take a vow of silence, but were disciplined if we broke silence.
Hand gestures, notes and other types of silent communication were discouraged unless absolutely necessary (as in “you’re standing on my toe!” as well as communications from superiors). Hand gestures were acceptable at meals, but only as related to the meal itself. This had evolved to a series of commonly used gestures (“pass the salt please”).
This was long before digital communications. The closest thing to it was the typewriter. IMHO, I think things like blogs and journals would be acceptable, but immediate communications, such as IM’s and social media would not.
The occasional “ouch” usually brought forth some of the involuntary laughter, although they would both bring forth the scowl of the superior.
The longest I have gone in silence was probably a 40-hour stretch, mirroring a particular devotional ritual.
I have often thought of taking a retreat at a local monastery consisting of three days of silence and service; my role as dad has pretty much ruled that out the past 15 years or so.