Wireless monitoring systems for critical applications in life science facilities

Users need to be aware that not all monitoring systems are equal. Choosing the right system is paramount to product protection and adding value to your process.

Quality standards in hospitals, blood banks, bio banks, the pharmaceutical industry etc are becoming more and more stringent. In any professionally run laboratories, product storage, microbiological processes and all environmental conditions must all be critically controlled, including product storage inside equipment.

It is impossible for a user to watch equipment all the time, and many monitoring systems have been developed to do it for you 24 hours a day, seven days a week; watching vital parameters like temperature, humidity CO₂ and pressure, and warning users if any controlled parameter moves outside set limits or if there are equipment or facility failures. But how do you choose the best system for your application with so many options out there? How do you know which system is best for your process?

You need to carefully look around at what is available. Local support is vital and any monitoring system provider understands that after-sales support is a major seller.

So what should a monitoring system do? Here are the top 10 most important aspects of a wireless monitoring system:

1. Secure recording of system data
2. Easy access onto the system
3. Easy-to-use software
4. Simplified system report generation
5. Reliable transmission of sensor data to the server
6. Accuracy and reliability of sensors
7. Local service and calibration of sensors
8. Alarm notification on parameter limits exceeded
9. Equipment failure notification
10. System redundancy

Choose your monitoring system carefully. By closely monitoring all the vital control parameters, quality loss in your product or experiment will be prevented. Furthermore, any equipment problems will usually be detected before total failure, allowing preventive actions. These and other benefits will improve your quality system and save money in the future: fewer products to be thrown away and medicines, blood and cultures maintained under optimum conditions.

A good monitoring system watches over the lab and notifies those responsible when something is wrong, even when no one is around. It should also provide the audit trails, historical data and graphical information needed to provide quality assurance to your suppliers, customers and auditors.

Every customer has different needs and wishes, ranging from small systems to the monitoring of entire buildings and facilities. Be aware when choosing a monitoring system as it may be constrained by the physical structure of the laboratory. A monitoring system that is flexible is the best way to go, as data transmission can be hard-wired, wireless or a combination. Furthermore, a monitoring system may require validation services so it will comply with all the appropriate quality standards like GMP, GLP, ISO and FDA 21 CFR part 11, so local support with experienced consultants is also vital.

Here are 10 more factors to consider if looking at a wireless monitoring solution.

1. Wireless frequency and transmission power. These are usually overlooked, yet 434 MHz has better range than 868 MHz inside buildings. Transmitters in the 434 MHz range run at a lower power and give off less radiation. Higher powered transmitters have a limit for how long they can transmit and this can slow down the system in terms of sending data. Lower powered transmitters in the 10 mW range also have less chance of interfering with other equipment on-site.

2. RSSI (wireless signal strength). Some systems do not automatically log or alarm on signal dropout, which is part of the territory with wireless technology. Wireless monitoring systems are not foolproof, but by intuitive design and additional compensation, signal dropout can be managed efficiently.

3. System redundancy. This comes in handy if signal dropout is an issue. A good robust wireless system should have sufficient redundancy to back up the PC/server and also allow sensors to keep on running in the event of a power failure on a battery backup system. Some systems have power failure watchdogs built into them and monitor the site for power outage issues, sending alarms if necessary.

4. Alarm notification system. One of the most important parts of the system is its ability to notify users of an event that may be detrimental to the facility or product. Ideally, SMS alarming should offer very detailed alarm messages to multiple people on standby. But is not enough these days - messages can get lost or users might not respond properly. You need a system that monitors the user’s response, offering automatic escalation to other people if necessary. In the worst-case scenario, the system should detect that no SMS messages can be sent, automatically switching to another form of alarming like BMS or a telephone dialler. This ensures that alarms will always reach the user, preventing product loss.

5. System backup. As per requirement of the 21 CFR part 11, electronic data-acquisition systems need to have a back-up and recovery option. Most systems will only offer manual back-up, often leading to data loss. A good robust system should offer a fully automatic, built-in back-up that makes back-ups of all data and which can be user-programmable. This is done to not one but multiple storage locations, offering good data security. For example, back-ups of one day will not exceed 500 KB, keeping annual database growth very low. This way, a system can store data for >30 years easily. The system should also provide alarms in case of back-up failure.

6. System watchdog. Many monitoring systems have no solution to monitor if the software is still running. In case of problems, users are mostly too late to react. Some good systems have built-in watchdogs able to autonomously react in case of server or software failure. These modems have a built-in back-up battery which also ensures proper alarming during complete blackouts. Signals can be sent to telephone diallers or BMS systems to alarm users so software failure issues can be immediately notified.

7. Sensor accuracy. There are many wireless monitoring systems on the market that have sensors with low accuracy. If one needs to monitor a specific temperature, one needs an accurate sensor that can be locally calibrated by a NATA-accredited facility. If we look at temperature, the more expensive sensors typically have better accuracy. For a temperature sensor to monitor critical laboratory equipment, a 4-wire (class A 1/10 DIN) pt100 sensor is appropriate. Many monitoring systems offer less accurate 3-wire sensors to cut costs, so be aware when looking at systems. It is often forgotten that bending a 3-wire cable will change the resistance value of the pt100, effectively changing the accuracy of the measurement. 4-wire pt100 sensors have a built-in cable compensation which protects against such changes.

8. Wireless substations. Look for wireless system substations that use a 16-bit analog to digital converter, which provides accuracy and stability not only at the day of purchase but for years and years. Some substations are supplied with a 7-point calibration and QC certificate for all channels, covering the whole measuring range.

9. Software. Choose a multiuser, web-based system. This means that every user can use every computer in the network (or from home) to log on to the monitoring system webserver. If software uses a client-software based solution, it is not possible to log on from every computer. Tedious installations need to be done and users normally do not have authorisation. Also, client licences are mostly paid. Furthermore, using a multiuser, web-based system allows the software to filter both alarms and information on each department level, so that people will only see the information that they want and need to see.

10. Compliance. Make sure the system you choose has hardware and software designed to comply with all necessary accreditations, like 21 CFR part 11, GMP, GAMP 5 and EN 300-220-V2. Since the FDA is not a certifying body, no company can claim to have been certified. In order to remove doubt, make sure the system provider has provided a 21 CFR part 11 compliancy statement in which all points of compliancy are worked out and documented.

In summary, if you want to safeguard your facility and valuable product, you need to be aware of the different types of systems on the market. Make sure you do your homework. There are some fairly basic systems and there are some really good wireless monitoring systems that will add value and confidence and, more importantly, protect the one thing that is the most important part of the whole facility: the product. If a cryo-freezer goes down and your monitoring system is inadequate, then that embryo is lost forever.