FAQ

EMF (Electromagnetic Fields)  and ELF (Extremely low frequency) are often used interchangeably and generally refer to low-frequency fields, such as 60 Hz magnetic fields produced by electrical distribution equipment (transformers, bus ducts, switchgear, and large feeders). These fields penetrate most building materials and can affect sensitive spaces like patient rooms, labs, imaging suites, and residential units if not properly accounted for.

RF (Radio Frequency) fields are high-frequency electromagnetic waves, typically generated by wireless communication systems, MRI scanners, broadcast antennas, security systems, and high-security facilities. RF fields require specialized shielding assemblies to prevent interference or ensure privacy and compliance.

Considerations is important in building design because uncontrolled levels of EMF and RF fields can impact occupant comfort, sensitive equipment performance, regulatory compliance, and building function. Early assessment allows your design team to avoid costly redesigns, choose optimal room locations, and integrate mitigation only where needed.

Common EMF sources (low-frequency 60 Hz):

• Electrical transformers, switchgear, panelboards, and bus ducts
• Main electrical rooms and mechanical/electrical shafts
• Large feeder cables and parallel conduits
• Emergency power systems

Common RF sources (high-frequency):

• MRI scanners and medical imaging suites (MHz range)
• Wireless communication systems (Wi-Fi, 5G infrastructure, antennas) (GHz range)
• Specialty spaces such as SCIFs, command centres, or RF-sensitive labs (Wide spectrum of frequencies).
• Industrial or research transmitters

In almost all practical cases with 60 Hz (power-frequency) magnetic fields, it is significantly more effective to shield the source rather than trying to shield the sensitive area.

Here’s why:

• Magnetic fields are very hard to block:
  Low-frequency (60 Hz) magnetic fields pass straight through most common materials (wood, drywall, concrete, aluminum foil, regular “EMF shielding fabrics,” etc.). The only practical ways to reduce them significantly are:

• High-permeability metals
• Creating distance (fields drop off with the cube of the distance in most real-world situations)
• Reducing or rerouting the current that is producing the field in the first place

Most of these options are only realistic at or near the source.

Shielding the source is usually smaller and cheaper The source of the field is typically a single point or small area (a wiring error, a transformer, a point-of-use device, a panel, or a service drop). Shielding that small area is easier and less expensive than trying to wrap an entire room in effective low-frequency magnetic shielding.

Distance is your friend, and source shielding maximizes distance benefits Fixing the source often reduces the field dramatically even many feet away, whereas shielding a distant area gives almost no benefit.

EMI assessments should be started as early as schematic design, typically around 50%DD. This is once room occupancy types are determined and preliminary electrical layouts are being developed.

Early assessment allows the design team to:

• Optimize room placement to avoid EMF/RF conflicts and interference.
• Prevent costly late-stage redesigns
• Plan for mitigation only where necessary
• Informed architectural, electrical, and structural detailing upfront

C-INTECH also performs concept-level assessments when equipment selections are still evolving.

Yes, mitigation can be added post-construction. However, it is usually more challenging, more invasive, and more expensive than addressing it during design.

Post-construction solutions may include:

• Retrofitting magnetic shielding materials behind existing walls
• Localized shielding enclosures

Whenever possible, early planning minimizes disruption and cost.

Shielding is incorporated directly into architectural assemblies such as walls, floors, ceilings and doors.

Key considerations include:

• Selection of shielding materials
• Detailing continuity at joints, corners, and structural interfaces
• Coordination with penetrations (mechanical, electrical, plumbing, AV, security)
• Ensuring door systems meet required attenuation
• Including shielding notes in specifications and architectural drawings

C-INTECH provides full detailing, integration notes, and coordination support to ensure any mitigation solution is constructible without sacrificing performance.

For accurate magnetic field modeling, C-INTECH requires:

• Single-line diagrams and electrical distribution layouts
• Feeder routing, including conduit sizes, spacing, number of conductors, and phasing
• Equipment locations
• Load data, including expected operating loads and diversity
• Voltage and current ratings for major equipment
• Surrounding room occupancy types

Providing this information early ensures accurate modeling and allows our team to identify any required mitigation while design options are still flexible.