Pharmaceutical 제조소 온도/습도계 정확도 관련 가이드라인 및 규정(USP, WHO)

 

1. 온도

USP 31 <1118> MONITORING DEVICES—TIME, TEMPERATURE, AND HUMIDITY

TEMPERATURE MEASUREMENT TECHNOLOGIES
The devices described in this section are those most commonly used to monitor temperature in the storage and distribution of drugs in North America. The measurement of temperature at extremes, such as close to absolute zero or above those reasonably expected to be experienced by drugs, is not addressed.

Alcohol or Mercury Thermometers

— These devices are based on the change in volume of a liquid as a function of temperature. Mercury thermometers are typically used in the ranges from 0 to 50 with a precision of about 0.1. [NOTE— Some local regulations apply to mercury-based thermometers. Alcohol thermometers may have a precision as good as 0.01, but they must be quite large to measure temperatures in ranges of more than a few degrees. Both types of thermometers may be designed to indicate the maximum and minimum temperatures measured. See Thermometers 21.]

Chemical Device— This is a device based on a phase change or chemical reaction that occurs as a function of temperature. Examples include liquid crystals, waxes, and lacquers that change phase, and thereby their appearance, as a function of temperature. Such materials represent the least expensive form of temperature measurement, but they may be difficult to interpret.
Other types of chemical sensors include systems in which a reaction rate or diffusion process is used to deduce a temperature equivalent integrated over time rather than the temperature at a specific moment in time such as a spike or critical threshold, for which a separate device may be preferred. Thus, chemical sensors provide a measure of accumulated heat rather than instantaneous temperature. It should be noted that these devices are generally irreversible; once a color change or diffusion process has taken place, exposure to low temperatures will not restore the device to its original state. Accuracy and precision vary widely among different types, to differentiate often limited by their ability or their ability to visually interpret diffusion distances.

Infrared Device— This is a device based on measuring the IR radiation from the article whose temperature is being determined; the IR radiation varies as a function of the object's temperature. The advantage of the device is that the article may be at some distance from the IR sensor. However, IR devices are expensive compared to other temperature sensors.

Resistance Temperature Detector (RTD)_저항센서(옴센서)

— This is a device based on the change in electrical resistance of a material as a function of temperature. Precision and accuracy depend on the quality of the electronics used to measure the resistance. Therefore, although RTDs are among the most stable and accurate temperature sensors, their accuracy may change with the age and temperature of the device as its electronic components are affected. A particular type of RTD uses platinum or platinum alloy wire as the sensor. These are referred to as platinum resistance temperature detectors (PRT or PRTD).

Solid State Device— This is a device based on the effect of temperature on either an integrated circuit (see Thermistor below) or a micromechanical or microelectrical system. These devices can attain the highest precision available and also have the advantage of producing a digital output. Their accuracy is typically limited by the accuracy of the calibrating system employed.

Thermistor— This is a semiconductor device whose resistance varies with temperature. Thermistors are able to detect very small changes in temperature. They are accurate over a broad range of temperatures.

Thermocouple— This is a device based on the change in the junction potential of two dissimilar metals as a function of temperature. Many metal pairs may be used, with each pair providing a unique range, accuracy, and precision. Precision and accuracy depend on the quality of the electronics used to measure the voltage and the type of temperature reference used. Accuracy may be a function of temperature reference used. Thermocouples have relatively poor stability and low sensitivity, but are simple and cover a wide temperature range.

Thermomechanical Device— This is a device based on the change in volume of a solid material as a function of temperature. For example, a mechanical spring, which expands or contracts as a function of temperature, thus opening and closing an electrical circuit or moving a chart pen, is such a device. Precision may be as good as 0.05, but in practice it is rarely better than 0.5. Accuracy is often in the range of ±1.0, but it may change with the age and temperature of the device.

 

Annex 9_WHO TRS 961 Temperature and humidity monitoring systems for fixe storage areas

Electronic sensors should be accurate to ± 0.5 °C or better.

 

 

2. 습도

Annex 9_WHO TRS 961 Temperature and humidity monitoring systems for fixe storage areas

Monitoring sensors should be accurate to ± 5% relative humidity (RH) and located to monitor worst-case humidity levels within the qualified storage volume.

 

 

3. 기타

압력계, 풍량계 등 : 별도 가이드라인 없음.