Siemens Oncor Linear Accelerators Recalled for Dark Current Radiation Risk
Siemens is recalling three Oncor Linear Accelerator units due to a potential dark current radiation risk during specific IMRT treatments.
The agency’s classification
FDA (Devices): Class II
Class II is a situation in which use of or exposure to a violative product may cause temporary or medically reversible adverse health consequences, or where the probability of serious adverse health consequences is remote.
This is the agency’s own classification, taken from its notice. The severity score below is our assessment, not the agency’s. How recall classes work
What this means for you
Our assessment, not the agency’s: severity 4/5 (Severe).
The hazard poses a serious risk of illness, injury, or structural failure. Stop using the product immediately and contact the manufacturer for a refund or repair.
Our severity reasoning: The recall is classified as FDA Class II, and the source describes a risk of significant radiation dose accumulation, which aligns with the rubric for Severe severity involving significant injury reports or high-risk medical device defects.
Plain-English summary
Siemens Medical Solutions USA, Inc. is recalling three units of the Siemens brand ONCOR series Linear Accelerator (Linac) systems. The affected units are identified by serial numbers 5281, 5385, and 5445. These systems are used to deliver X-ray photon and electron radiation for the therapeutic treatment of cancer.
The recall is issued due to a safety risk regarding a potentially existing dark current radiation phenomenon. This issue occurs when the Linear Accelerator is used in combination with IMRT or mARC (rotational IMRT) treatments using unflat (flattening filter free) beams. If a treatment plan involves many long periods of field shape changes, the dose from this dark current radiation may accumulate to a significant value.
The affected units were distributed worldwide, including in the United States (specifically Florida, North Carolina, New York, Pennsylvania, Tennessee, Utah, and Wisconsin) and in Angola, Brazil, Canada, P.R. China, Germany, India, Japan, Republic Korea, Poland, and Thailand. Users of these devices should contact Siemens Medical Solutions USA, Inc. for further instructions regarding the safety risk.
The recalled product
- Product
- SIEMENS brand ONCOR series Linear Accelerator Linac systems with component: any photon unflat beam option(Multiple X feature) in combination with the IMRT or mARC option. A family of linear accelerator systems is to deliver X-ray photon and electron radiation for the…
- Manufacturer
- Siemens Medical Solutions USA, Inc
- Affected units
- 3
Is your product affected?
Check your packaging against the codes below. If any of them match, the product is part of this recall.
Lot numbers (3)
- Serial Numbers: 5281
- 5385
- 5445
Distribution
Part of a larger recall action
This product is one of 2 recalled by Siemens Medical Solutions USA, Inc under a single FDA (Devices) recall action. The agency files each product separately, so the size of the action is not visible from this page alone.
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