The Warehouse Temperature Guide
Much of modern life depends on systems that we rarely see, working away quietly and competently in the background. Warehouse storage with precision temperature control and monitoring is just one of the services on which we all rely. Ensuring these warehouses operate optimally does not need to be a daunting task when the appropriate systems and procedures are in place.
Recent events, and the response to COVID-19 in particular, have undoubtedly made both nations and individuals aware of their vulnerability. We need to have confidence that pharmaceutical items such as vaccines are transported and stored in optimum temperature conditions at every stage of the supply chain.
Key to this confidence are environmental conditions, specifically temperature and humidity, since both are key factors that impact the quality of pharmaceutical products.
What’s more, at every stage in the supply chain there are possibilities for human error. The solution is always to ensure monitoring is in place. It’s not simply about conditions within the warehouse itself, but also temperature-controlled transport and packaging.
It’s therefore a cross-border activity, requiring specialist knowledge and experience. And however well-planned and constructed the warehouse where the items are stored may be, there will always be the potential for temperature inconsistencies due to different factors, such as vent location, condensation, solar input through walls or skylights, and shelf height.
The answer? Never assume, always monitor.
This begins with thermal mapping, which is not just important, but essential for compliance with international quality standards.
The first step is to accept that there will be temperature gradients even in the best designed and organized warehouses.
What is required is an approach that moves beyond the HVAC thermostat-based system, and one that is integrated with data processing and the creation of reports for ongoing assessment and re-assessment of environmental conditions in the storage facility.
Clearly, a new temperature warehouse coming into service should have a preliminary mapping procedure, but this is not a one-time-and-you’re-done activity. Any changes to warehouse layout, including the introduction of new product lines, as well as changes to HVAC thermostat setpoints, should be followed by a mapping exercise.
As one of ELPROs clients discovered after receiving specialist advice: “If the facility is mapped and adjustments are made later to the HVAC setpoints, the mapping will be invalid."
This is where knowledge and experience come into play. Specialists such as ELPRO suggest that the most comprehensive and accurate warehouse mapping studies are produced during periods of extreme weather, both winter and summer.
These are the times when internal areas closest to the exterior – predominantly walls, doors, and ceilings – are most prone to the influence of extremes of heat, cold and condensation.
Essentially, this is a risk-based form of assessment which will identify hot or cold spots that create critical issues, enabling management to implement CAPA (Corrective and Preventative Action) procedures.
In summary: wherever warehouses are located, they are subject to rigorous local and global standards. Warehouse mapping, that is the qualification and mapping of storage rooms and areas, is essential for the compliance of all GxP storage facilities.
Of course, individual companies can carry out their own mapping projects prior to the installation of a warehouse temperature monitoring system, but for many organizations, time, resources, or other issues may make this difficult or undesirable.
Whether choosing to map using in-house resources, or to use the expertise of a company such as ELPRO, a pre-installation survey and the collection of data relating to the warehouse facility is essential.
Fundamental to this is defining acceptance criteria relating to temperature in the warehouse. Nothing should be left out; everything from racking and shelving systems, HVAC plans and the insulation material used throughout or in specific areas needs to be assessed.
Essentially, this is a risk assessment survey. With that in mind, we’ll also examine ISO 9001 and ISO 17025 standards and how these relate to mapping and monitoring.
Mapping and data collection should focus on fully understanding and analyzing the internal space of the temperature warehouse facility. The results provide the information to assess how many temperature and humidity data loggers are required and where they should be located.
Once installed and the mapping cycle is complete,the results are assessed and built into a report. It should be clear by now that this is no small commitment for any company, and it’s one that they will have to carry out every time there is a change in use, relocation of items, or the building is extended or insulation replaced.
Wireless, automatic systems are undoubtedly the easiest to install and this can be done without major disruption to daily routines. Ensuring qualification and calibration standards are met is essential to successful installation.
Since warehouse temperature monitoring systems must be compliant, clearly the calibration of the equipment, whether carried out on-site by in-house specialists or external specialists, must be compliant within specific standards.
Calibration of sensors is required regularly, as over time they become less accurate and “drift” away from the correct calibration, due to component ageing and wear. It’s a good idea at this point to take a look at the options for calibrating sensors.
ISO 17025 is a standard specifically relating to testing and calibration. It covers a set of general competence and impartiality requirements across all industries. No matter how large or small, or how many employees, ISO 17025 applies to any laboratory involved in testing and calibration.
The standard not only covers the working environment, equipment, and all other technical aspects of the work, but also issues relating to personnel, confidentiality, and impartiality. Data management, security and record in calibration labs are all covered by ISO 17025.
ISO 9001, in contrast, is a non-industry specific standard relating to general management principles, rather than specifically to calibration and testing. It is not always necessary to have ISO 9001 in order to implement ISO 17025, although it is necessary to have shown compliance with minimum QMS requirements.
ISO 17025 offers two options; the first is to comply with the QMS standards by holding ISO 9001 certification, which is the case for most warehouse monitoring system specialists; the alternative is to meet the minimum standards within ISO 17025 certification (also known as Option A).
There are benefits in holding ISO 9001 certification when it comes to temperature warehouse monitoring. Since ISO 9001 has been developed to set standards in documentation, quality objectives and understanding risk, it has general benefits in terms of supporting leadership and clarifying risk assessment procedures.
The essence of temperature calibration is that it must be a consistent, reliable and documented reading of one piece of equipment against another which has been verified as accurate within a known set of parameters (and checked regularly by an accredited calibration laboratory).
A similar process exists for humidity using a slightly different process. In both cases, the two devices are observed and compared across a given period of time.
In fact, the temperature sensors used in warehouse temperature monitoring systems are extremely robust. Nonetheless, compliance and auditing standards require that these sensors are recalibrated or replaced every year. Maintenance contracts are often offered as part of the installation package.
There are various options available for calibrating the sensors of a warehouse temperature monitoring system. For temperature calibration, for example a calibration bath or calibration block (also known as a dry-block) can be used.
Humidity calibration uses a humidity generator or what is known as a reference solution to generate a defined humidity at a given temperature over a set period of time (for instance, 2 hours).
This allows the two devices to adjust to the relative humidity. For temperature warehouse sensor measurements, both baths and dry-blocks can be programmed to allow heating or cooling to a given point.
The simplicity or complexity of sensor calibration depends on several variables, and there are a number of options open to the temperature warehouse facility.
In-process calibration, performed on-site, can be fast, simple and economical, but it is less reliable. On-site calibration is less disruptive, can be performed to suit the client’s schedule and the daily operations of the warehouse temperature monitoring installation. The alternative is to remove sensors for laboratory calibration, but this creates more disruption unless the sensors are being replaced at the same time.
Self-calibrating sensors, as a relatively recent development, clearly offer an option that is less disruptive, but more expensive to purchase initially. There is increasing interest in the use of these sensors in many applications.
Pharmaceutical items and laboratory samples are precious. They're also surprisingly well-travelled! From lab to refrigerated truck to controlled temperature warehouse, those irreplaceable samples and medical supplies do get around.
In highly sensitive applications, for instance those involving cryogenic, dry ice and ultra-low temperatures (how low? Down to minus 200 degrees, that's how low!), real-time monitoring such as ELPRO's LIBERO G system is essential.
Monitoring temperature in the warehouse is just part of the journey. Clients need access to instant information about the locations of shipments and their condition wherever they are, both in storage and in transit.
Critical to these applications are monitoring systems which provide instant information on a range of factors including not only temperature and humidity, but light, shock and possible issues of tilt in storage.
A real-time monitoring system in a temperature warehouse allows you to immediately react if something happens. The most important requirements for a real-time monitoring system are:
fully automated data collection
easy to install and to maintain
immediate alarming via e-mail / SMS / phone call
fully GXP compliant
Extended battery length provides long term information on location and storage of vulnerable and high-risk items, matters that are essential to client satisfaction, patient safety and company compliance.
There are benefits to both cloud and on-premises data storage systems. The question that needs to be asked is one of compliance.
While on-premises storage provides control over data, it requires dedicated on-site resources and personnel, and there will be both set-up and ongoing management costs. When storing data on-premise, organizations need to have complete confidence in the physical security of the site and access to it.
Cloud storage systems have the advantages of being very cost-effective and easily installed by professionals. Systems such as ELPRO Cloud are literally plug and play and provide data immediately, as well as automatic alarms via SMS or email as soon as temperature limits are breached.
Cloud storage offers protection against data loss without major investment by the end user. Wireless sensors offer a safe and secure monitoring system without the need for complex engineering solutions on site.
Above all, it’s an extremely cost-effective way to guarantee compliance, create reports and reduce loss and damage. Companies using cloud-based software and storage solutions quickly recognize the benefits for both customer service and auditing.
In summary, pharmaceutical companies can ensure patient safety as well as traceable data for compliance purposes.