Technological innovation can be dramatic; it can also be over-hyped (think Segway). Other times technical innovation comes with less drama, often the result of a couple of engineers and their product managers thinking deeply about how to make their design even better for users and those who authorize the purchase — more functional, easier to operate, simpler and cheaper to implement and maintain and so forth. Of course, this is the way of most companies in the business of creating and selling ubiquitous industrial technologies including Pepperl+Fuchs, who recently introduced a highly refined operator interface terminal (OIT) purpose-built for sterile, cleanroom pharma processing environments.
Without being overly remedial, a clean room’s primary function in Pharma is to assure a sterile production environment to prevent products from being contaminated. Further, regulators classify these environments and compel Pharma to follow their specific mandates to control particulate and microbial contamination and assure the public’s safety. The FDA recommends that the area immediately adjacent to the aseptic processing line meet, at a minimum, Class 10,000 (ISO 7) standards during production. Drug makers can also classify this area as Class 1,000 (ISO 6) or keep the entire aseptic filling room at Class 100 (ISO 5). An area classified at an air cleanliness level of Class 100,000 (ISO 8) is appropriate for less critical activities such as equipment cleaning.
IT'S THE PEOPLE
According to P+F, clean room workers are a clean room’s largest contamination source. “People generate particles in the form of lint, skin flakes, cosmetics and respiratory emissions,” says P+F’s Lou Szabo. “To prevent particulates and particles from settling and accumulating on equipment, housing finishes must be hard, polished and free of corners, crevices or seams where dirt and other unwelcome visitors like bacteria might collect.” Szabo notes that the OIT can be a flashpoint of contamination “because that’s where humans tend to spend the most time.” Szabo explains that OITs must be designed, first, to eliminate any feature that promotes the accumulation of contaminates and be able to withstand the rigors of aseptic cleaning. “Housings must resist high-pressure, high-temperature washdowns, including live steam and aggressive cleaning chemicals as well as simpler SOPs such as spray and wipe,” says Szabo.
Pepperl+Fuchs say a major pharmaceutical company with extensive biopharmaceutical operations (one that shall not be named), recently embarked on a program to expand their aseptic manufacturing space to meet demand for a new drug. Operations quality supported by information systems and process controls was a priority, says P+F, and their customer wanted these systems to be accessed by OITs in its Grade A and B spaces mounted flush with the surface of the new space’s modular walls with minimal protrusion from behind. Plant requirements, as well as lessons learned from the initial plant construction, called for two aseptically designed OIT panels in theses spaces: One to communicate with the DCS and a second to communicate with the manufacturing execution system (MES) in a virtualized environment. Additional terminals were also specified to provide access to company intranets and corporate applications such as email, as well as room status displays (RSD). Pepperl+Fuchs’ customer, as well as the firm engineering the new capacity, both wanted the installation and maintenance of the OITs to be more cost-efficient.
PANEL DESIGN'S INHERENT EFFICIENCY
According to Pepperl+Fuchs, the existing workstation’s installation cycle time was long — between six and eight hours per unit for Grade B and A spaces, respectively. “A good deal of time was spent aligning templates, drilling holes, aligning fixtures, affixing rear fixing plates, and finally, sealing all exposed seams with a silicone room temperature vulcanizing (RTV) elastomer sealant/encapsulant,” says Szabo, “This translates to one workstation installation per day, or in the case where 20 or more are being installed, a ‘critical path item’ in the project schedule.”
The company’s improved panel design incorporates some well-refined installation features. To start, the OIT requires mounting the enclosure shell to the studs in the wall. The unit is then secured from the inside of the enclosure shell with a torque-limited drill. As the screws are tightened, a clever spring-activated latch deploys and tightens against the rear of the modular wall. “The shell can be secured in two minutes,” says Szabo, then the integral FDA-grade silicone gasket forms an air/bacteria seal between the shell and wall.”
The company says the door is never removed from the shell, so no electrical connections are disrupted, minimizing commissioning time. Power and Cat5 connections are made, power applied, and the single vault-like hinge swings the door back in place and the latches set, pulling the door firmly against the second layer of the silicone gasket. In the process, an air/bacteria seal between the door and the shell is completed. “Clean rooms are expensive to design, construct and operate,” says Szabo, “and reducing labor-intensive installation time to under an hour and reducing maintenance time by at least 50 percent is certain to save CAPEX and OPEX.”
MAINTENANCE REGIME STREAMLINED
The existing workstation’s preventive maintenance (PM) cycle regime was relatively time consuming as well, between two and four hours per unit for Grade A spaces. First a technician had to tediously and thoroughly remove the silicone RTV sealant around the door frame. Then, each unit underwent a maintenance function, primarily recalibrating the capacitive touchscreen. Once that was accomplished, all exposed seams had to be resealed. “The PM cycle translated roughly to two workstation PMs per day,” says Szabo “or in the case where 20 or more are installed, that meant up to 10 days of downtime.” With the new, enhanced unit, Szabo explained, an MTTR (mean time to repair) of 10 minutes is achievable with the Pepperl+Fuchs’ dual-seal gasket and latching mechanism system.
There is another benefit to this design, the company says. “Installation cost and impact on project schedules,” notes Szabo. “For the traditional installation, each unit requires up to a day to install, and with more than 20 units, that can take up to a month — likely placing the workstation installation on the critical path list.”
As far as Pepperl+Fuchs’ reckons, a traditional OIT panel requires a 6- to 8-hour installation and two people to install it, characterizing it as a “one-a-day” approach. To help understand the math, the company’s marketers projected associated expenses and created a table to illustrate the installed cost at a burdened hourly rate of $100. Multiply this across 20+ units and one can see the total price tag for installation grows significantly as the number of units climb. “A secondary point, but perhaps more significant,” emphasizes Szabo, “is that engineering firms are often incentivized to deliver a facility project on time, ahead of schedule and/or under budget. These incentives can range upwards of $100,000 per day.” Szabo explains that the chart shows that specifying the Pepperl+Fuchs solution could shave enough time off the critical path to generate savings and contribute to a substantial (net) early completion bonus. “In our example,” says Szabo, “at $20,000 per day, the net savings of using this enhanced workstation over the conventional bolt-in-RTV goop version pays for the workstations.”
Additionally, during this expansion, the customer noted the thin clients from the first phase were no longer available, while their industrial grade thin client was unchanged for seven years. The difference is in the industrial world, where they design for long lifecycles and purchase embedded processors at the beginning of their lifecycle, while in the consumer world, their design is based on end-of-life purchases of processors and an 18- to 24-month product lifecycle. Additionally, these COTS clients and KVM extenders do not have the temperature characteristics required for enclosure mounted equipment with no airflow and a 27°F temperature rise over ambient as design criteria.