Diagnostic Imaging
Specialized Climate Control for Medical Imaging Equipment
Advanced climate control and refrigeration solutions for diagnostic imaging centers. Systems designed to meet the critical requirements of equipment such as Magnetic Resonance Imaging (MRI), Computed Tomography (CT), Linear Accelerators (LINAC) and PET-CT, ensuring diagnostic precision, equipment lifespan and patient safety.
Magnetic Resonance Imaging (MRI)
MRI uses a superconducting magnet operating at cryogenic temperatures (-269°C or 4 Kelvin), cooled by liquid helium. The climate control system must meet three distinct needs: helium compressor (coldhead) cooling, gradient coil and RF amplifier cooling, and exam room climate control for patient comfort.
MRI System Technical Details
Helium Compressor (Coldhead)
Removes heat from the cryogenic system, dissipating 5-15 kW. Requires chilled water at 7°C with high stability.
Gradient and RF Coils
Generate 15-40 kW of heat during pulse sequences. Load peaks during image acquisition.
Magnetic Exclusion Zone
5 Gauss line defines area where ferromagnetic equipment is prohibited. HVAC components must be 316L stainless steel, aluminum or copper.
Benefits
Computed Tomography (CT)
The CT scanner uses an X-ray tube that rotates at high speed around the patient. During image acquisition, the tube generates intense heat that must be dissipated quickly. Thermal loads range from 15 to 40 kW with peaks up to 60 kW during acquisition. Humidity control is critical to prevent condensation on sensitive electronic components.
CT System Technical Details
X-Ray Tube
Generates peaks of 30-50 kW during shots, with rapid heating/cooling cycles. Requires system with fast thermal response.
Image Detectors
Temperature sensitive, require stability to maintain calibration. Variations > 2°C can affect image quality.
Rotating Gantry
Structure that rotates up to 4 rotations/second with embedded electronics. Generates continuous heat of 5-10 kW.
Benefits
Linear Accelerators (LINAC)
Linear accelerators are radiotherapy equipment that accelerate electrons to produce radiation beams for cancer treatment. They are the most critical equipment in terms of climate control due to the need for absolute precision in treatment and impossibility of interruptions. Thermal loads of 50 to 100 kW with mandatory N+1 redundancy.
LINAC System Technical Details
Klystron/Magnetron
Microwave source that accelerates electrons. Generates 30-50 kW of heat and requires chilled water at stable temperature for precise operation.
Waveguide
Accelerating structure that conducts the electron beam. Thermal expansion affects beam precision, requiring rigorous control.
Shielding Penetrations
1-2m concrete walls require mazes or deflectors for air ducts, maintaining radiological shielding integrity.
Benefits
PET-CT / PET-MRI
PET (Positron Emission Tomography) is combined with CT or MRI to provide functional and anatomical images simultaneously. Mainly used in oncology for tumor staging. Requires climate control for multiple systems simultaneously, including temperature-sensitive scintillation detectors, hot lab for radiopharmaceutical handling and uptake rooms.
PET System Technical Details
Scintillation Detectors
Crystals (LSO, LYSO, BGO) that detect gamma radiation. Temperature sensitive - variations affect energy and spatial resolution.
Hot Lab
Radiopharmaceutical handling (FDG, etc.). Mandatory negative pressure, exhaust with HEPA and activated carbon filters.
Uptake Room
Patients wait 45-60 min after radiopharmaceutical injection. Comfortable environment (22-24°C) with adequate shielding.
Benefits
Special Project Considerations
Magnetic Exclusion Zone (MRI)
Ferromagnetic equipment must stay outside the 5 Gauss line. This includes compressors, pumps and valves of the climate control system. Use 316L stainless steel, aluminum or copper components near the magnet.
Shielding Penetrations
Air ducts crossing radiation shielding must use mazes or deflectors to maintain protection integrity. Consult medical physicist for shielding calculation of penetrations in CT, LINAC and PET rooms.
Quench System (MRI)
In case of quench (sudden loss of superconductivity), liquid helium vaporizes rapidly (1L liquid = 700L gas). The exhaust system must evacuate 600-1000 m³/h to outside, with O₂ sensors and automatic alarms.
Power Quality
Imaging equipment is sensitive to voltage variations. Climate control systems must have soft-starters or frequency inverters to avoid current peaks at startup that could affect the equipment.
Vibration Control
Imaging equipment is sensitive to vibrations that can degrade image quality. HVAC systems must be isolated with dampers and operate with low vibration levels.
Humidity Control
High humidity can cause condensation on electronic components, especially in equipment with heating/cooling cycles. Maintain humidity between 30-50% RH for CT and 40-60% RH for MRI.
Hospital Chillers for Diagnostic Imaging
Our hospital chillers are designed with brushed stainless steel finish, meeting the most demanding requirements of diagnostic imaging centers.
Hospital Chiller with brushed stainless steel finish
Specific Features for Diagnostic Imaging
- 316L stainless steel construction - non-magnetic for MRI environments
- Temperature control ±0.5°C for critical equipment
- N+1 redundancy for 24/7 continuous operation
- Integrated HFD Flow Panel for monitoring
- Capacity from 5 to 50 TR for all equipment sizes
- Compliance with ANVISA and manufacturer specifications
High Complexity Diagnostic Imaging Center
Complete climate control project for diagnostic center with 2 MRI machines (1.5T and 3T), 2 CT scanners, 1 PET-CT and 2 linear accelerators. Integrated system with full redundancy, centralized monitoring and optimized energy efficiency.
Frequently Asked Questions
What is the difference between 1.5T and 3T MRI climate control?
3T equipment generates approximately 50% more heat than 1.5T, mainly in gradient and RF systems. The typical thermal load of a 1.5T MRI is 40-50 kW, while a 3T can reach 60-80 kW. Additionally, the magnetic exclusion zone is larger in 3T equipment, requiring greater distance for ferromagnetic HVAC system components.
Why is redundancy mandatory in linear accelerators?
Radiotherapy treatments follow rigorous dose fractionation protocols. Interruptions can compromise treatment efficacy and patient safety. Additionally, equipment can be damaged if overheated. Therefore, N+1 systems are mandatory, with automatic switching in case of failure, ensuring 99.99% availability.
How does the MRI quench exhaust system work?
Quench occurs when the magnet loses superconductivity and liquid helium vaporizes rapidly (1 liter of liquid = 700 liters of gas). The exhaust system is automatically triggered by oxygen sensors when the level drops below 19.5%. Large diameter dedicated ducts conduct helium to the outside, preventing asphyxiation in the exam room. The system must be capable of evacuating 600-1000 m³/h.
What is the importance of humidity control in CT equipment?
High humidity can cause condensation on CT scanner electronic components, especially in the gantry that operates in heating/cooling cycles. This can lead to short circuits, component degradation and detector calibration loss. Humidity should be kept below 50% RH, ideally between 30-45% RH, with active dehumidification control.
What are the special requirements for the PET Hot Lab?
The hot lab handles radiopharmaceuticals and must have negative pressure relative to adjacent areas to contain possible contamination. Air must be exhausted through HEPA filters and, depending on the radiopharmaceutical, may require activated carbon filters. Air renewal must be at least 10 changes per hour, with continuous differential pressure monitoring.
What standards regulate climate control in diagnostic imaging centers?
The main standards are: RDC ANVISA 50 (Healthcare Facilities), NBR 7256 (Air Treatment in Healthcare Facilities), NBR 16401 (Air Conditioning Installations), CNEN-NN-3.01 (Radiological Protection), IEC 60601-1 (Medical Electrical Equipment), ACR Guidelines (MRI Safety) and manufacturer specifications (GE, Siemens, Philips, Canon, Varian, Elekta).
Why choose Helioterm?
Over 50 years of experience in hospital climate control, with projects in diagnostic imaging centers throughout Brazil. Specialized team in requirements from manufacturers such as GE, Siemens, Philips, Canon, Varian and Elekta.