# 6 most common types of physical measurement uncertainties

Learn about the 8 most common types of physical measurement uncertainties, including systematic, random, instrument, human, environmental, model, inter-laboratory, and traceability uncertainties.

# 6 Most Common Types of Physical Measurement Uncertainties

Physical measurements are a fundamental part of scientific research and everyday life. However, all measurements have inherent uncertainties due to various factors, such as limitations of the measuring instruments or the environment. These uncertainties can affect the accuracy and reliability of the measurements, and it is essential to understand them to properly interpret the results. In this article, we will discuss the six most common types of physical measurement uncertainties.

## 1. Systematic Uncertainty

Systematic uncertainty is also known as bias, and it arises from a consistent error in the measurement process. It can result from problems with the measurement instrument, such as calibration errors or zero shifts, or from external factors that affect the measurement, such as temperature changes. Systematic uncertainty is generally predictable and can be minimized or eliminated by correcting the instrument or accounting for the external factors.

## 2. Random Uncertainty

Random uncertainty, also known as precision, is due to fluctuations in the measurement process. It arises from variations in the instrument’s sensitivity, or from environmental factors such as vibration or electrical noise. Random uncertainty is characterized by the standard deviation of the measurement, which reflects the scatter of the data around the mean. The random uncertainty can be reduced by increasing the number of measurements or improving the measurement instrument’s sensitivity.

## 3. Instrument Uncertainty

Instrument uncertainty is due to limitations in the measuring instrument’s accuracy and precision. It can be caused by factors such as the resolution of the instrument, the stability of the measurement over time, or the sensitivity to external factors. Instrument uncertainty is typically specified by the manufacturer and can be minimized by selecting a suitable instrument and following proper calibration procedures.