The GMP Relevance of Equipment Maintenance from FDA's Perspective

In our previous News "Dedicated Equipment Should also be Included in Cleaning Validation" dated 18.02.2026, we reported on deficiencies in a drug manufacturer's cleaning validation that were criticised by the US FDA. The cited observations referred to 21 CFR 211.67: 'Your firm failed to clean, maintain, and, as appropriate for the nature of the drug, sanitise and/or sterilise equipment and utensils at appropriate intervals to prevent malfunctions or contamination that would alter the safety, identity, strength, quality or purity of the drug product beyond the official or other established requirements, and you failed to establish and follow adequate written procedures for cleaning and maintenance of equipment.'

While this regulatory section is often associated primarily with cleaning, it explicitly includes equipment maintenance - an area in which the FDA identified significant deficiencies during its inspection.

FDA Findings

What did the FDA find?

Oxidised metals had already been criticised in the section on cleaning deficiencies. Now, the warning letter highlights deficiencies related to equipment maintenance, using the metal detection device as a key example. The FDA criticised the absence of an effective preventive maintenance programme, noting that the firm focused only on the physical presence of the detector rather than verifying its operational functionality. Furthermore, the detector had not been included in the company's qualification programme and therefore had not been properly qualified.

FDA conclusions

The FDA concluded that inadequate maintenance compromised the firm's ability to detect and prevent contamination risks. Inspectors also reported the presence of a metal screw inside a sealed drug container.

In response, the manufacturer stated that packaging activities would be suspended until the detector had been repaired and preventive maintenance measures implemented. However, the FDA considered these actions insufficient and requested additional corrective measures, including:

• full qualification of the metal detector
  and
• a description of periodic requalification strategy 
• a retrospective risk assessment of all batches that were manufactured while the metal detector was not functioning.

Conclusion

This Warning Letter emphasises that, from the FDA's perspective, cGMP compliance requires not only effective cleaning procedures but also comprehensive equipment qualification and a robust preventive maintenance programme.

As usual, the full Warning Letter is available on the FDA website.