Since laboratories involve variations of temperature and humidity levels, the recorded measurements can vary significantly. They both need to be kept within some limits in order to get accurate results, minimize the correction expenses and meet all the regulatory accuracy requirements. Many labs have failed to document the environmental conditions or stop calibrations when conditions weren't met. This has resulted in calibration managers reevaluating the methods they have used to monitor and document the environmental conditions in the labs.
Since chart recorders were not able to measure temperature and humidity levels accurately enough, managers in laboratories started using data logging instruments. The old models of chart recorders are difficult to maintain and calibrate, which was a big disadvantage compared to data loggers. Chart recorders come with a plenty of moving parts, which deteriorate and require more common maintaining over time. But data logging instruments use only advanced digital technologies, such as sensors, microprocessors, softwares, etc., all contributing to improved accuracy. They don't feature moving parts that can wear out, so they are easier to maintain and can provide better accuracy even after long periods of time.
Devices that use moving parts can fail at any time. To prevent failing, any kind of error or downtime, the moving parts need to be carefully treated and maintained. But most models of chart recorders waste a lot of time on maintenance. That's where data logging instruments gain another advantage – they do not require that common maintenance and are more affordable to maintain. Also, they use digital memory that only decreases in cost.