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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 that take place 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 it is necessary for the laboratory to 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 in a consistent manner, by multiple people, over and extended period of time.


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 which are, or incorporated in to 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 that is 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 or incorporated into a result that is reported to a customer will or is 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 upon the quality of the results delivered by the laboratory provides a mechanism to manage the quality assurance effort in an efficient manner. In addition, class equipment based on its potential quality impact will ensure that all equipment managed in a consistent manner.


The recommended categories are:

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

2. Quality Non – Critical Equipment is all equipment that although not used to make measurements which are either reported, or incorporated in to results that are 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 that are reported to the client, nor used to assure the quality of the results that are reported to the customer.


This classification is particularly useful 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 that is used to make measurements that are either directly, or incorporated into results that are, reported to customers. Quality non – critical equipment should include all equipment that is 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 of the laboratory temperature being reported to the customer to support the quality of the quality of measurements or results reported to the customer. The fact that the laboratory temperature is being reported to the customer would place the respective thermometer in the quality critical category, however, the fact it is only being used to support the quality of the reported measurements or results would place it in the quality non – critical category. Either option is correct, and it is up to the individual laboratory to make that choice. However, it needs to be made in a consistent manner and therefore needs to be clarified in the laboratory’s quality management system.


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