Is there a cell-service "blocker" for shuls?

Question

I've read that many shuls have "cell phone lockers" to encourage people who come for praying to store their phones prior to entering the shul.

It's a great idea, but, many shuls don't have this, or don't want to spend money doing this. Regardless, it's nearly impossible to force everyone to turn off their phones or place it in a locker. As an alternative, I'm curious if anyone has invented a complete cell service "blocker" which will block out all web as well as phone service from both inbound and outbound calls, as well as all texts, WhatsApp, etc. It won't completely discourage people from using their cell phones, but, at least, if they can't have their phone's ring, it will be less noisy, and it may ultimately discourage such people from using the phones altogether while praying.

Answer 1

Whether someone’s done this or not, I’m not sure, but I know the question was posed to Rav Zilberstein (don’t have the source on hand) of a hatzalah agent who missed a call because of this and as a result someone died. That’s probably why you don’t see this very often.

Anyway, the technology exists. It’s the same technology that keeps you from getting toasted whenever you turn your microwave on, or to keep a thief from using an RFID reader to steal your credit card information: a Faraday cage.

The way it works is that particles in the cage are designed as to distribute the charge evenly and equally across the cage, rather than allow it to pass through. This needs to be calibrated fairly precisely: the microwave doors are calibrated to trap microwaves inside, but you can call a phone you’ve left in there, and you can see the light produced from the bulb inside; an RFID bag may or may not allow visible light through, but the important part is that it blocks radio waves.

LTE frequencies range from 450 to 5925 MHz, so you may need two or three layered cages to cover the entire spectrum (and possibly watch for quantum effects). But, once again, use with caution in case of emergency.