Boston University’s Center for Integrated Life Sciences and Engineering (CILSE) is a state-of-the-art facility dedicated to the advancement of neuroscience research, systems and synthetic biology, housing a satellite vivarium, and featuring a cognitive neuroimaging center.
During the design phase, the magnetic field emission profiles of CILSE’s main and distributive electrical systems were meticulously modeled. The impact of the building’s switchgear, located directly above the neuroscience research and imaging center, was crucially assessed. Custom-manufactured equipment was reviewed in collaboration with users, and a stringent maximum magnetic field criterion was established to safeguard sensitive instrumentation from high electromagnetic fields. As a result, magnetic shielding systems were engineered for all affected laboratory spaces, ensuring optimal protection.
Post-installation, an extensive EMI survey was conducted to validate the effectiveness of the shielding. Time-dependent data was gathered from 81 locations, including the sanitized behavioral suites, and 60 Hz mapping data was recorded in areas shielded from the main power distribution systems. The successful mitigation of all electromagnetic interference (EMI) was confirmed, ensuring a pristine environment for cutting-edge research.
Executive Summary
Boston University – CILSE Shield Commissioning Survey
Overview
This commissioning survey evaluated the electromagnetic shielding effectiveness of specialized EEG and testing rooms at the Boston University Center for Integrated Life Sciences & Engineering. The assessment focused on AC Extremely Low Frequency (ELF) magnetic flux density, DC quasi-static fields, and compliance with health and performance thresholds.
Key Findings
- AC ELF Shielding Success:
All EEG and testing rooms met their specified performance objectives—0.353 mG RMS (1 mG p-p) at Bx, By, Bz axes at both 1m and 2m elevations. No additional ELF mitigation is required. - DC Quasi-Static Levels:
Elevated DC flux densities were recorded, largely influenced by the campus’s location within a train loop. Transient spikes (~1 second) were traced to electrical arcing between trains’ pantographs and overhead power lines. While these events momentarily affect ELF readings, no DC quasi-static tolerances have been specified for the facility. - Human Health Compliance:
In non-EEG shielded areas, ELF levels were compared against a 10 mG RMS tolerance. All rooms were well within this threshold, ensuring safe conditions for occupants. - Transient EMI Events:
Recorded DC spikes occasionally influenced ELF datasets but were short-lived and did not compromise compliance.
Methodology
- Measurement Tools: Bartington MAG-03MC1000 three-axis magnetometers and a FieldStar 1000 gaussmeter were deployed.
- Testing Procedure: Data was recorded over 10-minute intervals, processed with NI A/D converters, and analyzed via FFT for RMS and harmonic content. Grid surveys were conducted at 1m above floor height across testing rooms.
Implications for Researchers
- Reliable Shielded Environment: Researchers working with EEG and sensitive instrumentation can operate with confidence, as ELF shielding meets stringent tolerances.
- Awareness of Transients: While transient DC events occur due to external infrastructure, their short duration makes them operationally insignificant for most research applications.
Implications for Architects & Planners
- Design Success: Shielding design has been validated, confirming that architectural and engineering solutions effectively mitigate ELF interference.
- Contextual Constraints: Proximity to urban infrastructure (train loop) presents unavoidable DC interference. Future planning should account for site-specific external EMI factors.
Conclusion
The survey confirms that all shielded suites comply with performance objectives and health standards. Boston University’s CILSE facility is fit for advanced EEG research and other sensitive testing applications, with no further ELF mitigation needed. The only noted concern—transient DC flux spikes—is an environmental artifact, not a shielding deficiency.