Compiled by Eamonn Ryan
HVAC systems for pharmaceutical premises are designed to maintain a safe and hygienic environment.
Ryan Rennie, from the Spada-Rennie Group. Supplied by Ryan Rennie
The building of new pharmaceutical premises is not a common project in South Africa, but Ryan Rennie: Spada-Rennie Group, a specialist with over two decades of experience in the design of pharmaceutical factories, notes that there is much retrofitting and upgrading occurring.
He shares some insights into the intricacies of designing HVAC systems for pharmaceutical factories, shedding light on the unique challenges and meticulous planning involved.
Rennie emphasises the specialised nature of pharmaceutical HVAC engineering. “We’ve been in this industry for about 20 years,” he notes, explaining that the complexity and strict regulatory requirements of pharmaceutical manufacturing deter many from entering the field. The need for highly controlled environments means that HVAC systems must meet rigorous standards to ensure product safety and efficacy.
The key component of pharmaceutical HVAC design is the creation and maintenance of clean rooms. These environments are essential for preventing contamination during the production of pharmaceutical products. Rennie’s company focuses heavily on this aspect. “We refer to them as clean rooms because of their stringent requirements,” Rennie explains.
Clean rooms are classified based on their adherence to specific conditions such as temperature, relative humidity, and air cleanliness. For instance, in a Biological Safety Level 3 (BSL-3) laboratory, which might handle dangerous pathogens like tuberculosis, the air must be meticulously controlled. “We want the air to leave the room without re-entering, and it must pass through specific filters,” Rennie details. This process ensures that any contaminated air does not pose a risk to the environment or personnel.
Beyond pharmaceutical clean rooms
Rennie highlights the importance of collaboration, and within the Spada-Rennie Group there exists a range of services from consulting and project management to construction. An integrated approach allows for seamless execution of complex projects. “We handle everything from design to construction. This holistic method ensures that every aspect of the HVAC system is tailored to the specific needs of the facility.”
“Clean rooms are our primary business focus. Clients come to us because they want one entity responsible for the entire project.” This comprehensive approach contrasts with traditional methods, where different consultants are hired piecemeal, often leading to miscommunication and suboptimal results. “I’ve seen it time and again. When consultants who aren’t familiar with the complexities of clean rooms are brought in, the project often fails to meet the client’s needs, and everyone ends up blaming each other.”
“Since bacteria and viruses travel on dust particles, controlling particle levels in the air is crucial for maintaining a sterile environment.” Stockgiu | Freepik.com
Rennie warns about the importance of appointing experienced consulting engineers in these projects. “If clients go for the cheapest option, it usually backfires. The intricacies of clean room design requires a deep understanding of various engineering disciplines, and the risk of failure is too high to cut corners.
“We assess the consulting team members we need. This includes HVAC specialists, architects, electrical engineers, and fire services experts. We have a solid team, but we also partner with other specialists to provide the full range of services.”
A critical component of the design process is the User Requirements Specification (URS). “The client needs to produce a URS, which is a document that clearly outlines what they need and under what conditions. This specification is essential for ensuring that the facility meets regulatory standards and operates as intended.”
The URS is particularly important in pharmaceutical manufacturing, where a responsible pharmacist must ensure that the production conditions align with the requirements for drug safety and efficacy. “It’s not just about classification; it’s also about temperature and relative humidity. These factors are major cost drivers in the design and construction of clean rooms.”
Rennie provides some context on the costs involved. “Typical air conditioning for an office might be about R1 000 per square metre, but for a clean room, the costs can be perhaps R8 000,” he says, reflecting the advanced systems required to maintain the stringent conditions necessary for pharmaceutical production.
From initial planning to final execution
“We create detailed drawings and renderings of the facility, which we present to the client before construction begins. This allows clients to visualise the final product and make any necessary adjustments early in the process.”
The design and construction of clean rooms for pharmaceutical manufacturing involves significant financial and technical considerations. “The numbers get big very quickly,” Rennie acknowledges. “For that reason, you’ve got to write that URS intelligently to make the project feasible. You have to question what is actually needed and be highly precise in defining the requirements to avoid unnecessary expenses.”
Once the URS is established, the design process begins, focusing on minimising costs by distinguishing between primary and secondary areas. “Primary areas are classified spaces, while secondary areas are for packing, storage or other purposes that don’t need classification. This strategic planning helps manage costs without compromising the quality and compliance of the facility.
A pharmaceutical manufacturing entity encompasses various specialised areas, each with unique requirements such as raw materials brought in through quarantines. DC Studio | Freepik.com
“An architect who understands GMP (Good Manufacturing Practice) is essential,” Rennie states. GMP dictates how people and products should flow through the facility to maintain safety and efficiency. Alongside the architect, a skilled HVAC engineer is crucial to manage the costs and technical aspects of the facility’s air-conditioning and ventilation systems.
During the URS phase, it’s also crucial to determine which standards the facility will comply with. Rennie mentions several key standards, including ASHRAE guidelines, ISO standards, and those set by various regulatory bodies like SAPRA (South African Health Products Regulatory Authority) and the World Health Organization (WHO). “These standards constantly evolving and staying updated is vital.”
Additionally, organisations like the International Society for Pharmaceutical Engineering (ISPE) play an important role in advancing clean room technology and methodologies. “They are constantly looking at new ways of doing things to improve efficiency.”
One of the most challenging aspects of clean room design is budgeting. “Arriving at an actual cost with all these moving parts is quite difficult,” Rennie admits. The complexity of the requirements, combined with the need for precision and compliance, makes the budgeting process a significant hurdle. However, by working closely with clients and thoroughly understanding their needs, one can develop accurate and feasible budgets.
There is a continuous evolution of this field. “These things are being rewritten and advancing all the time with organisations and standards bodies constantly updating guidelines and best practices. Innovations in clean room design and technology will continue to drive improvements in safety, efficiency and cost-effectiveness.”
A pharmaceutical manufacturing entity encompasses various specialised areas, each with unique requirements such as raw materials brought in through quarantines,” Rennie explains. After production, the products move to a finished goods warehouse, which also requires controlled conditions, albeit less stringent than those in the manufacturing area. “Generally, the products are sealed, so there are no special filtration requirements. It’s more about maintaining the right conditions,” he adds.
Particle control and airflow management
The execution phase involves providing the client with different options for finishes and ensuring the facility’s design minimises contamination risks. “For example, doors are designed to be high level with flat surfaces to avoid accumulation of dust and other particles,” Rennie says. Since bacteria and viruses travel on dust particles, controlling particle levels in the air is crucial for maintaining a sterile environment.
Stuart Karovsky, general manager at Air-Dale Engineering (Cool Breeze Airconditioning SA). © RACA Journal
Effective cooling and air management are vital for clean rooms. “Generally, you need an air handler. Standard hardware units are often insufficient for the precise airflow and air changes required in clean rooms. Custom-built air handlers are essential to meet these specific needs. The air handler is designed based on conditions such as humidity control, cooling capacity, airflow and fan size. It goes through a comprehensive engineering process,” he explains.
The choice of cooling systems involves several considerations. “There are different options for generating the heating or cooling requirements in the space,” Rennie notes. Options include DX units, VRF condensers or chillers, each with its own set of advantages and applications. However, not all cooling methods are suitable for clean rooms. “Evaporative cooling, which uses wetted media, is not acceptable for these highly controlled environments because it introduces particles into the airstream,” Rennie points out.
Evaporative cooling, while energy-efficient, is generally unsuitable for highly controlled clean room environments. “Evaporative cooling systems are water-hungry and have a short lifespan due to mineral buildup and other issues. This method also introduces particles into the air stream, which is unacceptable in sterile environments.”
Humidity control is a vital aspect of clean room environments. “Humidity can be controlled through heating and cooling. We pass air through a coil to absorb moisture and then reheat it. For extreme dehumidification, specialised dehumidifiers with desiccant wheels are integrated into the system. These systems can achieve sub-25% humidity levels, which is necessary for manufacturing certain products that are highly hygroscopic,” he adds. Although these systems are expensive and complex, they are essential to prevent moisture absorption during the manufacturing process.
The location of a facility significantly influences the choice of HVAC systems. “If you’re building a low-energy facility, you should consider the geographic location because the size of the equipment needed can vary drastically,” Rennie notes. Coastal areas, for example, pose challenges for cooling systems due to higher humidity levels.
Validation and compliance
Once a clean room facility is constructed, it undergoes a rigorous validation process. “Validation is where we test our design against the URS. This phase involves comprehensive testing, including particle counts and temperature mapping. We perform detailed particle count tests after the facility is built but before the client takes over. This includes filter integrity or DOP testing and recovery tests to ensure compliance with regulatory standards.”
Clients also conduct microbial testing to measure the levels of micro-organisms in the environment. “These tests are highly structured and form the basis for obtaining a license to operate the facility. If you don’t pass the validation, you don’t get your license.
“After the initial validation, maintaining the facility involves regular monitoring and filter changes,” he adds. The Building Management System (BMS) plays a key role in ongoing maintenance by providing real-time data and alerts.
“‘The numbers get big very quickly,’ Rennie acknowledges.” © RACA Journal
Selecting the appropriate HVAC equipment is a critical aspect of clean room design. Rennie outlines several factors that influence these decisions, such as budget, availability, and the specific needs of the facility. “We have established relationships with various suppliers as well as manufacturing our own range of AHUs, allowing us to choose the best systems for each project,” he notes. The choice of equipment is tailored to ensure optimal performance and compliance with industry standards.
Cool Breeze Airconditioning weighs in on evaporative cooling
As businesses and industries increasingly prioritise sustainability and cost-effectiveness, evaporative cooling emerges as a viable alternative to traditional air conditioning systems.
“With evaporative cooling you would change the air in a particular space around 30 times an hour – so essentially bringing in new air and removing the stale air. The rate of air change can vary depending on the varying circumstances. This concept of cooling differs from conventional air-conditioning which relies on air recirculation to get to the temperature required,” says Stuart Karovsky, general manager at Air-Dale Engineering (Cool Breeze Airconditioning SA) which has been in this business since 1964.
For this reason, evaporative cooling has emerged as a contender, particularly for large spaces like warehouses and commercial buildings.
“Evaporative cooling offers significant advantages, especially for cooling expansive areas with high ceilings or roofs. Compared to conventional air conditioning, it presents a more economical solution in terms of both upfront capital costs and ongoing operational expenses,” argues Karovsky.
The key difference lies in the absence of energy-intensive compressors and refrigerants typical of conventional AC units. Instead, evaporative cooling harnesses the natural process of water evaporation to cool the air, resulting in lower energy consumption and negligible carbon emissions.
“It’s a green, sustainable solution. The process relies on the interaction between water and air, leveraging the high surface area of water to extract heat from the air. This not only naturally cools the air but also maintains a comfortable indoor climate without relying on harmful chemicals,” says Karovsky.
Its use in pharmaceutical applications depends entirely on the user requirements, and where maintaining a stable temperature around 25°C evaporative cooling can meet these specifications effectively. However, the effectiveness of these systems is lessened in regions with high humidity levels, such as coastal areas or tropical climates.
But in dry climates prevalent in regions like the highveld, Northern Cape, Namibia and Botswana, he emphasises the efficiency of this system in such environments. “Dry climates are perfect for evaporative cooling.”
Unlike traditional air-conditioning systems that recirculate air, evaporative cooling introduces fresh air from outside while simultaneously expelling stale air, ensuring a constant influx of clean, oxygen-rich air. The water management process within evaporative coolers uses fresh mains water supply to prevent bacterial growth.
“There’s no standing water in our systems. Water is circulated and evaporated quickly, with any remaining water drained out when the unit is not in operation. Fresh water circulation and drainage mechanisms ensure that standing water, a potential breeding ground for bacteria, is effectively eliminated.” This reassurance is particularly relevant for industries like pharmaceuticals, where stringent air quality standards are imperative, says Karovsky.
The unique operational dynamics of evaporative cooling, place the focus not only on temperature regulation but also on maintaining air quality and minimising environmental impact. “In large warehouse applications, the need for unrestricted movement in and out of buildings poses a challenge for conventional AC systems. Evaporative cooling, on the other hand, benefits from open spaces, facilitating air relief and circulation without compromising cooling efficiency.”
Cooling extends to the hospital, as on the case of this Netcare hospital project covered in a previous issue of RACA Journal. © RACA Journal
Regarding operating expenses, the representative addresses concerns about water usage and associated costs. “While evaporative cooling systems do utilise water, the cost of water in many regions is relatively low compared to electricity expenses. Thus, the primary operating costs typically stem from electricity consumption rather than water usage,” he continues.
With a focus as much on pharmaceutical factories as well as event venues and industrial settings, evaporative cooling systems are highly adaptable to various spatial configurations. In fact, Karovsky explains that evaporative cooling finds widespread use across a spectrum of sectors, ranging from residential to commercial and industrial settings.
“From domestic households to large-scale industrial facilities, it offers a cost-effective and environmentally friendly solution. Retail spaces, warehouses, factories and supermarkets all benefit from the energy efficiency and clean air provided by evaporative cooling systems.
“In warehouse scenarios, a straightforward setup involving roof-mounted units dispersing cool air evenly throughout the space is common. However, for more intricate layouts or events, various ducted solutions are employed to direct airflow precisely where needed. While the primary setup typically involves roof-mounted units, the use of ducting allows for customised airflow patterns tailored to specific requirements,” notes Karovsky.
Regarding equipment diversity, he clarifies that evaporative cooling units come in modular designs suited to various project sizes and specifications. “Our units are modular and come in standard sizes, ranging from compact units for domestic use to larger systems catering to industrial and commercial applications. While there are different models available, the core design principles remain consistent across our product range.”
Cool Breeze evaporative coolers originate in Australia: “Our commitment to quality is evident in the high standards upheld by our Australian-manufactured units. While cheaper alternatives may exist, the longevity and performance of our products set them apart in the market,” says Karovsky.
Air-Dale Engineering has the technical resources – and the willingness – to collaborate closely with consulting engineers to ensure optimal system design and functionality. “While consulting engineers may spearhead design efforts, our expertise in evaporative cooling allows us to provide valuable insights and support throughout the process.”
Ducting
Fabric ducting is commonly used in pharmaceutical environments. Fabric ducting eliminates drafts and hot/cold zones by uniform air distribution and minimising temperature differences through the occupied area as low as 0.5°C.
Dave Mitchell, general manager Africa of Fabricair talks of an installation at pharmaceutical premises in a project covered in a previous RACA Journal issue. Working in pharmaceutical (or food) processing plants is often uncomfortable for workers because of the cold temperatures of anything from 16°C down to 8°C.
An example of FabricAir’s ducting in a pharmaceutical warehouse. © RACA Journal
The chill factor of air conditioning can take that to almost freezing point. This means workers can’t work long shifts and also get sick from regular exposure to different temperatures. Mitchell says that in one study at pork producer Danish Crown, for instance, sick time off was reduced by as much as 30% just by using fabric ducting.
“The VarioDuct system installed at Nkunzi Pharmaceuticals is the first installation of its type in South Africa. It’s relatively new on our list of products, having come onto the market about two years ago. It’s specifically designed to be versatile in summer and winter where we have the widely varying ambient temperatures creating a challenge of getting air to a comfortable level, particularly so in winter.
“There is a servo motor on the duct which drives the diaphragm within the duct. In summer it will allow the hot air out of the top half of the duct and the cold air will naturally fall – which is what drives the air down to comfort-level. In winter, the top half of the duct is shut off with holes in the bottom half that opens the bottom holes, releasing the pressure so the airflow flows down, forcing past the cold air to the comfort level where the people are,” explains Mitchell.
“Every ducting system is specially designed and built for a project. In the case of Nkunzi, because it’s a pharmaceutical warehouse with the ducting high up, there were concerns about getting heating to the bottom in winter. That’s why our product was selected. With conventional ducting system at heights, the efficiency changes with the seasons and becomes less effective in winter.
