Power Protection

As medical imaging continues to migrate from film to a digitally oriented environment, the need to maintain a consistent flow of clean power increases. Not only must the imaging technology be protected from damage and failure, but also at risk is the integrity of the data they output. Roberta Katz, director of healthcare ? life sciences solutions at EMC Corp, Hopkinton, Mass, explains that as radiology and cardiology evolve into digital infrastructures through PACS, “there is a big push for quality, efficiency, and the highest availability [while still managing to] protect, manage, share, and archive patient information for years.”

And 24/7 availability of patient information is a critical requirement. To accomplish this crucial need, the medical field is “investing in technology like they never have before,” states Mark Greenlaw, senior director of storage product marketing at EMC.

Per Ron Wodka, medical OEM business development manager at Tripp Lite, Chicago, hospitals tend to “think about everything but power” with regard to planning for and purchasing medical-imaging equipment.

Todd Henderson, global accessories product manager at GE Healthcare, Waukesha, Wis, explains, “The NFPA-99 Standard for Health Care Facilities requires that emergency power from a backup generator be up and online within 10 seconds or less if a power outage occurs in a facility.”

The emergency power system at Mount Carmel Health Services, Columbus, Ohio, for example, restores power in less than 3 seconds, notes David Jerome, operations manager of radiology services at Mount Carmel; “But less than 3 seconds can be dramatic.”

Relying on the generator is not an adequate method for backup power. In the seemingly small amount of time between the loss of power and the powering of the generator, critical electronic imaging equipment and information systems are improperly shut down and at risk for damage, information can be lost, and procedures are halted. But, complete loss of power represents only part of the story. Most power problems exist in the unseen?those milliseconds of a power loss, known as a power glitch. As Tom Stryker, sales manager of CPN Power Inc, Somerville, Mass, explains, “There are many types of power problems.” Power anomalies include voltage sags, surges, transients, harmonics, electrical noise, and frequency deviations. These anomalies often represent tiny fluctuations or electrical impulses in the power lines. A power surge, for instance, is a brief increase in voltage.

According to Tripp Lite?s Wodka, “Surges often go unnoticed, lasting only 1/120th of a second, but they are much more common and destructive than you might think.”

Power glitches are a danger to sensitive electronic imaging equipment. “Imaging systems are providing us with greater medical insight; however, at the same time, the electronics are more sensitive than ever before to power anomalies,” explains Henderson. When a power anomaly appears, errors can occur within the data systems or the actual images. A tiny blemish on a crisp, sharp image can result in the need to recapture the image. The error requires the patient to be rescheduled, or even worse, could cause a misdiagnosis. Wodka says that imaging equipment requires clean power in order to capture and transmit images without a fault.

Faults and errors not only are wasteful and possibly harmful to medical-imaging processes, but they also represent loss of time, revenue, and patient confidence. Flawed images and downtime of equipment equate to costly patient rescheduling and high service costs that add up over time. Viswas Purani, director for emerging technologies at American Power Conversion Corp (APC), West Kingston, RI, explains that hospitals must reduce errors, cut costs, eliminate the nonvalue add, and improve patient care.

Power outages and anomalies also can cause expensive damage to the imaging equipment and data systems. Craig Kalie, sales representative for POWERVAR Inc, Waukegan, Ill, explains that in addition to equipment destruction, power problems cause disruption and nuisance problems, like lock-ups that require rebooting or shutting down the equipment. Disruption to the process equates to loss of time and revenue. Another hidden cost is the constant degradation of the equipment and components over time when smaller electrical disturbances occur.

Multiple Solutions

There is good news answering to the dangers of power mishaps: Multiple solutions exist. A multitude of power-protection devices are available, such as isolation transformers, surge suppressors, power conditioners, double-conversion power conditioners, and uninterruptible power supplies (or UPS devices). “[Isolation transformers] eliminate common mode voltages and help mitigate power disturbances,” Kalie explains, noting that they also reduce electrical noise. A surge suppressor?also known as a transient voltage surge suppressor (TVSS)?diverts excess voltage. Standard power conditioners actually condition the power by stopping several of the power anomalies from causing problems with medical-imaging equipment or data centers. The double-conversion power conditioner (DCPC) operates like a UPS device in that the mechanism uses a power-regeneration approach to ensure that lag time in adjusting for voltage fluctuations is nonexistent and, according to Stryker, “that all power problems are eliminated, with the exception of the complete [power] outage.” An online UPS device provides continuous power, and a line-interactive UPS is on standby mode, supplying backup power in the event of a power outage.

GE Healthcare?s Henderson adds, “The double-conversion UPS remains the preferred backup methodology for critical applications.”

A variety of codes on emissions and safety qualify protective equipment as “medical grade,” Purani explains. Power-protective devices within the patient vicinity, or 6 feet from the patient, must meet certain medical standards related to low leakage currents. The IT spaces?the data centers and network closets?are not within patient vicinity and, therefore, are not required to meet the same standards. Greenlaw adds that medical-grade backup also has a higher level of redundancy to provide “backup to the backup.”

Powering Modalities

The exact power-protection requirements for a medical-imaging environment or data center actually depend on the configuration and type of equipment, as well as the electrical distribution. The options and requirements vary as radiology equipment evolves. Some medical-imaging equipment is growing in size and drawing more power; for example, CT is becoming more complex and sophisticated, with its number of slices per second increasing. Other equipment?ultrasound, for instance?is shrinking in size, becoming more compact and more mobile. But the standard is the same: Good, clean, quality power is essential. Purani says that the UPS is becoming “increasingly a must-have.” The size of the UPS or other protection device depends on the size of the equipment the device is protecting, but generally, the device needs to be able to support the high-power demands of the medical-imaging equipment.

Recommendations in protecting equipment from power problems sometimes vary by critical application. For example, Kevin Harris, marketing manager of TEAL Electronics Corp, San Diego, says, “Cardiac cath labs and cardiovascular suites cannot lose power,” noting that both applications need a guaranteed power source to avoid loss of life during a critical procedure, making a larger, more expensive UPS absolutely necessary. Tripp Lite, as well as other power-protection companies, generally recommend one backup device per power supply. Some hospitals, however, might not use a UPS on an MRI or CT unless the power source has proven to be bad, because larger UPS devices can be expensive.

CPN Power recommends that hospitals use a central UPS device with power conditioners to support multiple modalities, because protecting individual units could potentially involve huge costs, Stryker explains. In CPN Power?s recommendation, a central unit protects the PACS data equipment as well as the radiology and cardiology equipment; in this case, the hospital connects 12 pieces of equipment on a 750-kVA central UPS and power-conditioning system, with an additional growth of three to four more units. Stryker says that this method “lowers the cost per suite of protection” in terms of electrical distribution, electrical usage, cooling, and reduced service costs.

Hospitals do not have to make power-protection decisions alone. Many power-consulting companies exist to evaluate the hospital?s power-quality and power-protection needs. Wodka recommends that hospitals hire a power-quality and reliability specialist?in other words, an independent consultant to work in conjunction with the imaging-equipment OEM. Once medical-imaging equipment and data centers are properly protected, the hospital needs to develop and maintain a sound reassessment plan. Hospitals should reassess power-quality needs, according to Kalie, “anytime new equipment will be added or if there are unexplainable problems with the systems.”

To prevent equipment failures and damage, to reduce costs and downtime, to increase revenue and availability, and to focus on patient care, facilities must recognize the strong benefits of protecting medical-imaging equipment and data centers up front as well as electrical planning. Efficient equipment operation and uptime represent good planning for the continuity of the hospital?s business. As Mount Carmel?s Jerome asks, “Why wait for a problem to happen?”

Nici Lewis is a contributing writer for  Medical Imaging. For more information, contact .