What is X-ray irradiation process
The X-ray irradiation process uses photon radiation for a variety of applications, including sterilization, decontamination, and material modification. The X-ray process is compatible with most materials and has good permeability to dense products.
In contrast to nuclear gamma rays, which are emitted in all directions, high-energy.
High-energy X-rays are high-frequency, short-wavelength electromagnetic photons. These are emitted by high-energy electrons when they are deflected by atomic nuclei. The efficiency for X-ray emission increases with the electron energy and the atomic number of the target material. Thin sheets of tantalum are used for the long targets that are needed for irradiating tall pallet loads of products. The X-ray energy spectrum is very broad, with the maximum photon energy being the same as the kinetic energy of the incident electrons. With maximum X-ray energies of 5MeV or 7MeV (million electron volts), the product penetration is greater than that provided by large, uncollimated arrays of cobalt-60 sources .
What is X-ray exposure?
An X-ray machine is an electron beam where electrons are generated and accelerated to obtain energy. Electrons are produced in devices with energies ranging from 5 to 7.5 megaelectron volts (million electron volts), with power up to hundreds of kilowatts (kilowatts). The electrons are then focused on a specific metal target with a high atomic number. X-ray radiation is produced through a process called bremsstrahlung, which produces electromagnetic energy (photons) in the same energy range as gamma rays.
What is X-ray irradiation used for?
X-ray irradiation can effectively treat a variety of materials with different densities, structures and orientations. Some examples of processed product types include:
Chinese and Western medicine
Combination drug/device product
Tissue base and biological products
Animal retail products
Cosmetics and toiletries
What are the benefits of X-ray irradiation treatment?
X-ray irradiation is a safe, reliable and efficient method for processing products of various densities. The combination of shorter exposure time and improved dose uniformity ratio (DUR) makes X-ray irradiation a viable processing option for many products. Similar to electron beams, X-ray processing is driven by electricity.
The benefits of X-rays include:
Improve the penetration of photon energy, similar to gamma rays.
Fast and efficient target processing, convenient for products from cartons to full pallets.
Flexibility-the ability to mix products with different dosage requirements within the same irradiation cycle.
Compared with gamma ray and electron beam irradiation, it reduces material degradation by shortening the processing time and reducing the maximum dose of the product.
By improving DUR, it can handle strict dosage specifications.
Incremental lap-based dose delivery provides flexible and precise process definition in a wide dose range.
The internationally recognized and consistent standard ISO 11137 supports X-ray sterilization. This standard describes a method of verifying the dose to achieve a prescribed sterility assurance level (SAL).
X-ray irradiation support services:
In addition to irradiation sterilization, we also provide customers with laboratory testing and technical support solutions for each sterilization design stage from product development to daily processing.
Our radiation technology team? Guide customers to complete the irradiation verification process, provide solutions for special project needs, and support routine treatment through quarterly dose audits.
The Radiation Technology Center (RTC) supports our customers in radiation testing activities such as product testing, dose determination and dose verification. RTC provides high-precision dose delivery for verification, dose mapping, dose audit and research purposes.
Our testing services provide customers with verification support and conduct microbiological testing of their products through irradiation. As part of our complete radiation verification plan, we will develop an agreement to collect all test and verification data, summarize the results and make recommendations based on your product, and provide continuous support through a dedicated radiation technology team project manager.
Adopting X-Ray Sterilization for Medical Devices
The use of X-rays as an alternative modality to either gamma irradiation or electron beam irradiation for the sterilization of medical devices has become a topical subject.
High-energy X-rays (bremsstrahlung) are a form of ionizing energy that provide an attractive alternative to nuclear gamma rays for irradiating large packages and pallet loads of medical devices. Their penetration is sufficient to treat multiple pallet loads of low-density packages with low dose uniformity ratios.
X-ray sterilization is a clean process that does not leave a toxic residue in the products. At typical dose levels, the small temperature rises do not damage plastic materials. Modern, high-power X-ray generators have processing rates and costs comparable to other sterilization methods.
X-rays are concentrated in the direction of the incident electron beam, and their angular dispersion decreases as the electron energy increases. The high intensity in the forward direction enhances the efficiency for X-ray utilization and allows a reduction in the size of the irradiation room. Only a few product carriers need be in the treatment room at one time. This minimizes the treatment time per carrier and facilitates the irradiation of small batches of products with different densities and dose requirements.
X-ray Sterilization methods
In order to obtain good dose uniformity and efficient X-ray utilization, product loads must be irradiated from opposite sides by passing at least twice by the X-ray target. The optimum thickness for two-sided treatment increases as the package density decreases. With 5MeV X-rays, the optimum thickness is about 2.6m (8.5ft) for an average density of 0.1g/cm3.
Processing of products and materials with high-energy X-rays was first proposed over 50 years ago and commercial use of this method for sterilizing medical devices was initiated about 15 years ago. Several electron beam facilities in Europe, Japan and North America are equipped for both electron beam and X-ray sterilization, and a new facility intended only for X-ray sterilization will soon be operating in Belgium. X-ray processing is growing as a result of recent increases in the beam power ratings of industrial electron accelerators, which can generate intense X-ray beams.