GE Plastics' LNP(1) Thermocomp(1) HSG Composites Offer Better Alternative To Lead In Radiation Shielding Applications

Pittsfield, MA - GE Plastics has launched a new line of thermoplastic materials with high specific gravity (HSG) that may replace lead in many healthcare applications that call for radiation shielding. Medical equipment and devices that produce x-rays and gamma rays must be shielded to protect operators, clinicians, patients, and sensitive electronic components from tube leakage and room scatter. GE's LNP(1) Thermocomp(1) HSG radiation shielding, high-density compounds enable x-ray shielding solutions without the use of known toxic substances, while providing greater design freedom and higher-volume manufacturing with lower total part cost through the use of injection molding.

"Lead continues to present health and disposal challenges to manufacturers of radiation-shielding products," said Clare Frissora, market director, Healthcare, GE Plastics. "We're very pleased to offer a new alternative to lead that can enable these manufacturers to design safer solutions. Our LNP Thermocomp HSG x-ray shielding compounds also provide the opportunity for design and cost advantages over lead in a wide range of healthcare applications."

Due to increasing regulation of lead for toxicity and environmental risks, manufacturers are seeking new replacement materials. For example, the European Union's Restriction of Hazardous Substances (RoHS) directive calls for the near-elimination of lead in most electrical and electronic equipment. In addition, lead has design drawbacks. Lead-encapsulated glass plates for protection against x-rays must be very thick, limiting usage and design options. Further, lead shielding can have "hot spots" – areas where x-rays can penetrate.

GE's LNP Thermocomp x-ray shielding compounds have been shown to shield radiation up to the effectiveness of lead without leakage or hot spots. They are based on tungsten – a non-hazardous HSG material – in nylon 6. LNP Thermocomp HSG x-ray shielding compounds can be made with enhanced stiffness, strength, and impact resistance for demanding injection-molding applications.

GE Healthcare chose an LNP Thermocomp HSG x-ray shielding compound for several applications within its OEC 9800 x-ray machine, which is designed for procedures such as cardiac, vascular, and orthopedic surgeries. The shielding material is used in the collimator, which absorbs stray radiation and limits the x-ray exposure dose. With LNP Thermocomp HSG compound, GE Healthcare gained many advantages over lead beyond compliance with environmental regulations. The transition from machined and stamped lead to injection-molded engineering resins may help enable tighter tolerance specifications and greater part consistency, enhancing the performance and safety of the x-ray equipment. Avoiding secondary operations required with lead, plus combining multiple components in one part, reduced total manufacturing time, system cost, and complexity.

"Replacing lead with LNP Thermocomp HSG compound in our x-ray equipment may help us provide a higher level of safety for patients and caregivers," said David Barker, engineering manager, GE Healthcare. "Part-to-part consistency made possible by injection molding facilitates uniform shielding, and gives designers precise control over the amount of radiation filtered through their devices. The fact that this compound is environmentally responsible and reduces overall system costs was a welcome bonus."

GE Plastics is working with Thogus Products Company, a custom injection molder, to create new grades of the Thermocomp HSG material that match the specific gravity of lead, including a flexible version for specialized applications. The companies are also jointly working to develop an elastomeric grade with high elongation that will deliver exceptional design flexibility.

This composite offers the potential to replace other shielding materials for similar cost and performance advantages. Applications include: x-ray shielding devices and containers, housings, x-ray tubing components, dental x-ray equipment, and nuclear medicine containers.

Future applications for LNP Thermocomp HSG x-ray shielding compounds could benefit from the capabilities of GE's Global Application Technology (GApT) centers, such as user-centric design elements, injection molding application-specific testing, and teardown analysis, which is used to disassemble existing units made of traditional materials such as metals (e.g., lead) and identify part consolidation opportunities attainable with thermoplastic injection-molded parts.

GE's LNP Thermocomp HSG x-ray shielding compounds are commercially available. They are manufactured in the United States, and are available globally.

SOURCE: GE Plastics