What are the requirements for using cell phone jammers in prisons?

In recent years, prisons, labor camps and detention centers across the country have invested money to build or rebuild mobile phone jamming systems. It is hoped that illegal use of mobile phones will be eliminated, mobile phone management in supervised places should be strengthened, and supervision work can be carried out smoothly.

1. Take action against all current public communication standard mobile phones CDMA, GSM, DCS, PHS, 3G (CDMA2000 / TD-SCDMA / WCDMA), and shall not affect the normal operation of other electronic equipment systems in the prison;
2. Within the scope of the prison (including but not limited to prison rooms, walkways, corridors, windows, etc.), the effective shielding rate should reach 99.9% or more;
3. In the production area, the effective shielding rate should reach 99% or more;
4. In narrow narrow spaces (including but not limited to conversation rooms, storage rooms, toilets, etc.) and more hidden places where violations may occur, the effective shielding rate should reach 99.9% or more;
5. Unshielded areas (including but not limited to administrative buildings, armed police buildings and surrounding units or residential areas, etc.) must be kept unobstructed;
6. After achieving the shielding effect, it must pass the electromagnetic radiation safety test of the shielding part;
7. Fully retain the output redundancy of the equipment, extend the service life and adapt to future development needs;
8. The system must use a centralized power supply.