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Management of Equipment in an ISO/IEC 17025:2017 Accredited Laboratory

Part 1: Classifications of Laboratory Equipment

2 Schemes for Classifying Laboratory Equipment

The wide range of activities in testing and calibration laboratories means that no single classification scheme can address the requirements of all laboratories. It is for individual laboratories to develop optimised schemes to meet their specific requirements. This section discusses several potential schemes for classifying laboratory equipment. These are suggested options that can be optimised to meet the specific needs of the laboratory.


Whichever classification scheme(s) are selected, the laboratory must adequately define them within its quality management system. In addition, it is also necessary to provide clear and detailed instructions to enable the schemes to be applied consistently by multiple people over an extended period.


2.1 Equipment Quality Criticality Classification

The equipment in modern testing and calibration laboratories can be used for a wide range of activities. These typically include

1. Making measurements that are, or incorporated into results that are, reported to the customer. An example of this would be a laboratory balance used to weigh a sample.

2. Making measurements to assure the quality of the results that are reported to the customer. An example of this would be a set of standard weights used to calibrate the laboratory balance.

3. Other purposes that do not include making measurements that are either reported to or used to quality assure the results reported to the customer.


The consequences, and therefore the risks, of a quality failure associated with each of these activities, is different. For example, a quality failure associated with a measurement incorporated into a reported result will directly affect the quality of that result. Conversely, a quality failure associated with a measurement that is neither reported to a customer nor incorporated into a result reported to a customer will or used to support the quality of such results can be expected to have no consequences for the customer.


Classifying laboratory equipment according to its capability to impact the quality of the results delivered by the laboratory provides a mechanism to manage the quality assurance effort efficiently. In addition, class equipment based on its potential quality impact will ensure that all equipment is managed in a consistent manner.


The recommended categories are:

1. Quality Critical Equipment is all equipment used to make measurements that are either reported or incorporated into reported results to the customer; this should include computers that control or collect and process data from equipment that make measurements that are either reported or incorporated into results reported to the customer.

2. Quality Non – Critical Equipment is all equipment that, although not used to make measurements that are either reported or incorporated into results reported, to the customer, but is used to assure the quality of such measurements or results.

3. Non – Quality Equipment is all equipment not used to make measurements or produce results reported to the client, nor used to assure the quality of the results reported to the customer.


This classification is particularly useful for routine maintenance and calibration intervals when making decisions regarding the frequency of calibration and maintenance.


When defining this scheme within a quality management system or writing instructions for its use, it is important to clearly define the boundaries of each category. Quality critical equipment should include all equipment used to make measurements that are either directly or incorporated into results reported to customers. Quality non–critical equipment should include all equipment used to assure the quality of reported measurements and results. As an example, the room temperature of the laboratory is often a significant contributor to the overall quality of measurements and results. The temperature of the laboratory is often specified to be within prescribed limits. Therefore, the laboratory temperature is often measured, monitored and recorded. If the value of the laboratory temperature is not reported to the customer, the thermometer used to measure it should be categorised as quality non–critical, as would the equipment used to calibrate this thermometer. The question of whether the thermometer used to measure the laboratory temperature is either quality critical or non–critical arises in a scenario e made in a consistent manner and therefore needs to be clarified in the laboratory’s quality management system.


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