Simon Rice, GMP Validation & Quality Co-ordinator at Connect 2 Cleanrooms explains how to reduce downtime during testing, maintenance and calibration periods
Downtime for a facility comes at a cost, and it isn’t cheap. Whether the cause is a planned shutdown for maintenance or an unforeseen closure due to contamination or equipment failure, any lost time should be minimised as much as possible as the impact can be far-reaching.
From labour costs, including outside contractors and idled operators, to production costs, including wasted product and materials—downtime can seriously affect overheads.
Through design, effective maintenance, and calibration, downtime can be reduced so that only the minimum time to maintain, test, and requalify the facility is required.
Contamination Control Strategy (CCS)
The use of a Contamination Control Strategy (CCS) will effectively define critical control points that could potentially result in the contamination of a facility, and how these points can be assessed. By correctly implementing a CCS, the risk of downtime due to contamination will be greatly minimised. From the first steps of design, to the procedures introduced, and operator competency, a CCS should be used through the full lifecycle of the cleanroom, to risk assess potential contamination points and controls implemented. Whether this is through cleaning procedures such as rotational cleaning, the use of continuous monitoring, or staff training, the impact of a well-managed CCS cannot be discounted.
How design affects downtime
The reduction of downtime starts earlier than you think in the lifecycle of the cleanroom. During the initial design of the facility, future maintenance, service, and validation must be considered. This can be through designing a layout that allows engineers ease of access to critical systems that make up the cleanroom, or through the use of systems that can be replaced and tested without breaking the integrity of the cleanroom.
During planned shutdowns of the facility, routine checks of the HVAC system and any other systems required to support the use of the cleanroom are checked. If the facility has been designed to allow easy access to these systems, engineers will be able to work efficiently, without obstructions slowing down the process.
Another consideration at the time of design would be component selection. When reviewing the impact of maintenance on the cleanroom, the less invasive the maintenance and testing the better. For instance, if components such as room-facing lights are considered during design, changing lights would not require a full requalification as the room integrity would not be broken. Minimising this requalification would result in shorter downtime of the facility.
At the time the facility is installed, a complete O&M manual will provide the information required for the operation and maintenance of the build. This manual might include details of the building’s construction, including as-built drawings, and instructions for maintenance including manufacturer’s information for efficient and proper operations.
The ability to segregate zones of a facility, to allow maintenance in one area while carrying out routine operations, will greatly reduce the impact of a shutdown. The use of decentralised air handling systems provides the option to shut down sections of the facility while maintaining routine operations in others. If there is suitable space, segregated change areas for each area will allow staff to enter and leave rooms that are still in operation, while other areas are down. Traditional Air Handling Units (AHU) service the whole facility so it’s much more difficult to shut down separate zones.
Planned Preventative Maintenance (PPM)
Incorporating PPM into your maintenance schedule should result in a reduction in downtime. The concept of PPM means shifting from a run-to-fail strategy, to proactively seeking the prediction of required maintenance. Even when a facility is functioning normally.
In cleanrooms, PPM usually begins with monitoring. The use of routine or continuous monitoring of your facility is critically important to maintaining operations in a cleanroom. Not only will continuous monitoring pick up any out-of-specification results, such as high temperatures or increases in particulates, but the data can be analysed to determine any potential trends that may result in significant downtime to remedy.
Trend analysis of temperature, humidity, and viable or non-viable monitoring may show results heading towards the high end of acceptance limits. Could this red flag be a result of failing systems? A shorter preventative downtime to remedy the change in results would be preferable over a full failure of the system, which could result in a significantly longer shutdown. This trend analysis can be used to determine proactive maintenance for the future based on the visibility of reduced efficiency, as displayed by internally determined out-of-trend limits.
Equipment calibration
Routine continuous monitoring of a cleanroom usually requires supplementary monitoring systems to measure the environment of the room. Whether these are temperature and humidity data loggers or a particle counter, there is a requirement for these systems to be regularly calibrated to ensure the accuracy of the results generated. Without calibration, incorrect results may not flag potential issues which could result in facility downtime.
The calibration of equipment may result in site downtime if not planned ahead of time. For example, if a particle counter is required to carry out operations, and the particle counter is off-site for calibration, the cleanroom cannot function. There are several options to counter this potential situation:
* Purchasing spare equipment will allow for equipment to be sent off-site for calibration without impacting operations. This will also prevent the impact on site operations if there is a failure of a critical system, as the faulty equipment can be easily replaced with a spare. Keeping this equipment qualified and calibrated is still a necessity, but calibrations can be staggered, leaving at least one unit online at all times. There will be an initial outlay of expense with purchasing a second unit, but the benefit of keeping the facility operating should outweigh the initial cost of purchasing and maintaining spare equipment.
* Using a local calibrations service will prevent additional delays in downtime. Transit of the equipment and delays in customs can take up a large time that equipment is off-site, so by carrying out calibration in the UK the impact of equipment being off-site and therefore potentially resulting in downtime is minimised. Additionally, by using local services and reducing transit time, the risk of damage to potentially expensive equipment is minimised.
* If possible, using a loan piece of equivalent equipment provided by the company that is calibrating the equipment may be the best option to prevent downtime. By utilising this option, there is no requirement for purchasing additional equipment, and if the loan equipment is delivered before shipping the equipment for calibration, there should be no impact on operations. The potential barriers associated with this are whether the calibrations company provides this as an option, and if so whether the loan equipment is available at the time required.
In-house or independent testing?
The use of a combination of third-party and in-house validation and testing can combine to produce counter-measures to site downtime. By using in-house testing and monitoring, swift responses to any problems that may have occurred can be logged and actioned. Staff who regularly work in these areas are likely to spot potential deviations early on, and with an efficient system to capture these faults, they may be fixed before any room downtime is required.
The use of third-party validation and testing will provide an independent and more thorough test of the facility than can be achieved through in-house testing. Requalification of a cleanroom at regular intervals, whether determined by regulatory bodies or internal risk assessments, will assure that the cleanroom is operating within the expected acceptance criteria, and if any failures are observed, investigation and remedial work can be carried out by trained staff to reduce the impact on routine operations.
The use of calibrated equipment when executing requalification works is paramount to assuring that the cleanroom is operating as intended. Without proof of calibration, the results produced cannot be guaranteed to be accurate. If there is no guarantee that the results are accurate, the testing may need to be carried out again, which will add to the already experienced downtime.
Through a holistic and proactive approach to monitoring and maintenance, you not only gain better visibility of the operations of your facility, but you can raise productivity and cut back on costly downtime.
Connect 2 Cleanrooms is an integrated cleanrooms service provider offering Design and Build, Validation and Equipment Calibration services.
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