Manual Data Collection
Surprisingly, manual humidity / temperature monitoring and data collection methods are still in wide use today. Such methods typically involve one or more operators recording initialed readings on a regular basis from a fixed read-out device (such as a digital thermometer or hygrometer). These readings are usually entered on a prominently displayed chart next to the area of interest, such as a refrigerator, freezer, or chamber.
Recording temperature and humidity readings in this manner has some obvious advantages: there is minimal equipment to purchase, there is next to nothing to maintain.
However, manual systems can be very expensive to operate and are often unreliable. Most problematic however, is the time lost to manually gathering temperature and RH data. One hospital estimated labor costs of 3,000 hours per year of valuable nursing time was taken up performing routine checks on monitored environments. The same hospital frequently had to deal with missing data that impacted their need to meet regulatory requirments. Critical products were at risk by this unreliable, error prone system of monitoring temperature and humidity.
In this instance, the risk to product increased during off-hours, when limited resources resulted in missed temperature checks. In such cases, problems can undetected for days, resulting in serious damage. For the above reasons, many Life Science facility managers can easily justify the costs of a move from manual methods to an automated system.
Chart Recorders
Chart recorders are one of the most popular ways to automatically collect and locally display data. They record and display operating data on paper charts which are then changed regularly and archived, usually on a weekly basis.
Chart recorders are relatively easy to deploy, power wiring is usually all that's required, and they have often been included as a built-in feature of various equipment. Although expensive, chart recorders are relatively simple to operate and provide local display of real-time and short-term historical data.
But for all their advantages, chart recorders are still dependent on manual processes to function properly. Charts and pens must be changed regularly or else valuable information is lost. Being mechanical devices, they cannot provide the kind of measurement accuracy that critical monitored environments require. Chart recorders are prone to periodic mechanical failures and require frequent re-calibration.
In addition, in today's increasingly "connected" world, chart recorders are now recognized as isolated devices that cannot be monitored, alarmed, or otherwise accessed remotely. This serves to make data retrieval, required when the auditors arrive, a time-consuming and tedious process.
Centralized Humidity / Temperature Monitoring Systems
Centralized monitoring (CM) systems consist of a network of remote sensors that are literally wired back to distributed or centralized input panels. Not to be confused with Building Automation Systems, a CM system is an auxiliary system tailored to the specific monitoring and reporting requirements of a particular industry.
CM systems offer many advantages including remote temperature monitoring, alarming, and reporting. By avoiding the need for manual data collection and chart replacement, such systems are a significant time-saving alternative to chart recorders and manual methods.
The main drawback to CM systems is that they are costly, prone to system-wide failures, and are limited in their ability to display localized information. A typical CM system requires expensive data acquisition equipment as well as a proprietary hard-wired network. Installation and wiring costs can often be prohibitive, particularly in older buildings. The large capital expense of such systems can also lead to a protracted budget approval process.
Centralized systems are also prone to global failures that can result in missed records and unreliable reporting. For example, system viruses, computer crashes, network failures, power outages, or operator errors can interrupt the data collection process throughout the whole system.
An often overlooked issue with CM systems is their inability to display data on a localized basis, a key requirement in many industries. Instead, data can only be viewed or retrieved at a central location.
Pharma / Biotech
