We’ve had some issues in complex network and plant rooms with EMI signals that in one case demanded we move equipment – are these sorts of issues typical and what is your advice to circumvent them in planning?

A: Every computer room will have a network of conductors that may absorb electromagnetic signals from the computer room’s cabling through a process known as inductive coupling. Unless this energy can be quelled it will be radiated into unsecured areas of the facility.

There are a number of ways to get around these issues, including shielding cabinets with an electrically conductive and grounded screen, as well as radiation absorbing material. Controllers or machines may have connections filtered and any keyboards fitted with quarter-wavelength stubs.

Conductors to watch out for include steam pipes, air vents, raceways, conduit and cable troughs. Also look out for metal wall frames and window frames. These emanations can be suppressed by grounding all metal conductors within and around the network room.