FDA Warning Letter - Alarm Management

Date: 25 May 11
Link FDA 483 (PDF - New Window)

Observation

b. During routine operations, if there is an alarm event (e.g., time out, high and low temperature for washing and siliconizing, instrument line failure, jacket gauge failure and steam header failure) during the wash and depyrogenation process, the [redacted] Stopper Washer captures the alarm condition via a print out and the data is retained with the / manufacturing batch record. The Quality Compliance Manager confirmed that the alarmed events are not periodically reviewed or trended to assure that the [redacted] stopper washer and/or wash and depyrogenation process is not drifting from the validated state of control;

Comment

This is an interesting observation relating to the management of alarms and the use of periodic review and / or trending to demonstrate that the system is not drifting from the validated state. This can relate to almost any automated or monitoring computerised system.

When specifying and designing an automated control or monitoring system careful consideration should be given to the alarms generated by the system. A process for identifying and prioritising alarms is critical to the success.

In very general terms those alarms that have quality impact will be set to operate at the point of Out-of-Specification which should result in a quality related deviation. Normally when there are Quality Critical Alarms then then there will be associated warnings, with a setpoint at a level appropriate to take action, before the Quality Critical Alarm is tripped.

The trip points are alarm setpoints should be clearly rationalised and approved by the Quality Unit.

Periodic Review / Trending
To demonstrate the process is operating within the specified range a review of the alarms generated during the process should be reviewed routinely. This should initially be performed during the initial performance monitoring (performance qualification) of the system. This should ascertain that the warning levels are appropriate (provides operators with sufficient opportunity to rectify the problem before a breach in quality limits) and if the process is controlling within the quality critical limits.

Following the PQ, all breaches in specification must be reported through the batch record / deviation system. This should provide a trend of the critical alarms.

For the warnings a periodic review should be performed, which may use statistical analysis based on an acceptable number of alarms (process capability) to ensure that the system is continuing to operate in control and without degradation of performance.

The frequency of review and the depth of the review should be based on the impact of the computerised system and the operating history.

As stated at the start of the comment by building the alarm management in to the requirements and design of the system, the statistical analysis can be performed by the control system or the alarms stored within a database to ensure that they can be access for trending and review purposes.

Useful information

ANSI/ISA–18.2–2009 - Management of Alarm Systems for the Process Industries
EEMUA 191 - Alarm Systems- A Guide to Design, Management and Procurement