Calibration of a device is carried out to minimize the uncertainty in measurements. It helps in reducing the errors and brings the measurement to an acceptable level. With repeated use and over a period of time, all equipment tends to degrade and that affects its accuracy and precision. In the medical device industry, a drift in the measurement is unacceptable. Regular maintenance and service are needed for an instrument to work accurately and at its optimum.

For medical device manufacturers, the health and safety of patients remain their top priority. Therefore, the precision and accuracy of a device is of utmost importance. To safeguard the interest of the users and to ensure that public health and safety isn't compromised, the medical device industry is regulated by strict standards, including FDA's 21 CFR Parts 11 and 820, Quality System Regulation (QSR) and ISO 13485.

FDA's Code of Regulations

Equipment calibration must be carried out routinely. (Credit: RS Calibration Services)

Title 21 of the FDA's Code of Federal Regulations defines the calibration requirements for equipment. According to section 820.72, manufacturers have to inspect, measure, and test equipment to ensure that it is suitable for its intended use and that it is capable of providing valid results. It also states that manufacturers must have provisions to handle, preserve, or store the equipment. These activities have to be recorded and documented.

Calibration must be performed on a regular basis to check its accuracy and precision and, if any errors are found, corrective measures have to be taken and adverse effects, if any, must be evaluated and documented.

The procedures for how to calibrate an instrument must be easily accessible to the designated staff of the company. Procedures should include how to calibrate the instrument and should include the acceptable range for accuracy and precision. The procedure that is used to inspect, measure, and test equipment should be traceable to national or international standards.

In a nutshell, FDA guidelines for calibration of a medical device require the following:

  • Equipment calibration must be carried out routinely, as per the company's written directions.

  • Calibration of every device that needs to be calibrated must be documented.

  • Acceptable limits for accuracy and precision must be specified.

  • Calibration personnel must be trained.

  • Calibration standards must be traceable to the national standards, in-house standards (if necessary), or other acceptable standards have to be used.

  • Provisions have to be made for evaluating adverse effects caused by the defective equipment, and corrective measures must be taken.

Requirements for Calibration

Calibration. As per FDA's medical device calibration requirements, all medical device companies need to have procedures in place that include instructions and acceptable limits for accuracy and precision. If a medical device fails to meet these standards for precision and accuracy,

FDA will evaluate whether failing to meet the standards can have an adverse effect on the patient. If potential risks are discovered, then the manufacturer must calibrate the medical device to improve its quality until the standards are met and must document all procedures involved.

Standards. If the standards for calibrating a medical device are absent, FDA states that relevant national, international, state, or local standards need to be applied. If no standard exist, the manufacturer must form its own set of requirements, and the medical device must be calibrated to meet those requirements.

Documentation. Part 21 CFR 820.72 states that manufacturers must document all the points of calibration, including the following:

  • The date the device was picked up for calibration.

  • The name of the staff who performed the calibration.

  • When the next calibration is due.

All of these records need to be made accessible to the designated personnel of the company. For an instrument calibration program to remain in compliance with FDA, it is important to maintain a calibration schedule. Missed calibration cycles can compromise the quality of the product, resulting in non-compliance.

This article was written by Edward Simpson at RS Calibration Services, Pleasanton, CA. For more information, visit here .