FDA
Warning letter 711320, ZOLL Medical
FDA’s device center told ZOLL Medical Corporation that defibrillators, MRI-conditional ventilators, electrodes, and sensors made in Chelmsford, Massachusetts, are adulterated under the quality-system rules, and that at least one ventilator malfunction was reported to the agency months late.
The inspection ran from February 27 through April 15, 2025. The letter names X Series and Advanced automated external defibrillators, Zoll 731 MRI-compatible ventilators, OneStep electrodes, and Accuvent sensors. FDA says ZOLL’s CAPA procedure did not do what it claimed. A March 2025 request on a pediatric electrode with burnt tin under the gel was rejected as a first-time event even though the request itself flagged arcing and a burned patient. Ventilator complaints that led to a Class I recall were coded as user error, no fault found, or no product returned, so the trend never tripped the firm’s own trigger. After that CAPA closed, six more MRI-compatibility complaints arrived and no new CAPA opened.
The letter also says a life-supporting ventilator shut down unexpectedly near an MRI. ZOLL became aware on June 20, 2024. FDA received the medical-device report on March 10, 2025 — past the 30-day clock. Separately, FDA writes that RescueNet Live software, which the letter says generates a secondary alarm from monitor data, may itself be an unapproved device if it is doing more than displaying alarms the monitor already made.
The inspection was taken under the old Quality System regulation. Corrections, the letter says, have to meet the Quality Management System Regulation that took effect February 2, 2026.
fda.gov — ZOLL Medical Corporation — 711320 — 04/30/2026
These notes paraphrase and quote one public FDA warning letter. They are not legal advice. A warning letter is an administrative notice, not a court judgment. Redaction marks such as (b)(4) are FDA’s.