19 Steps to Better Cleanroom Construction

March 15, 2011
Make critical decisions early, and get all the right people involved.

As the demand for complex cleanrooms in the life sciences grows, construction challenges mount. Making the right decisions during the building and commissioning phases of cleanrooms will help to ensure that they are successful, better integrated, more operable and sustainable. Generally speaking, teamwork among designers, operators, maintenance people and builders that focuses on project timelines will achieve the best results. The suggestions below will help drug and device manufacturers step back and better envision the whole facility during the build process.

1. Plan constructability: First and foremost, bring on the mechanical detailers early to confirm whether conceptual design ideas have achievable timelines and are constructible. Is the overall project of sufficient difficulty to require a 3D model? What type of detailing should be confirmed prior to the release of RFP’s to equipment vendors and mechanical subcontractors? Answers to these questions will ensure all selected subcontractors have the full detailed scope in their subcontract.

2. Conduct pre-RFP planning: Complete a commissioning plan that fully details all procedures, documents and testing to be completed for all scope of work. The plan should also include system definition and be completed prior to release of the RFP’s.

3. Allow for equipment connections and clearances: Enlist thoughts and opinions early in the design phase from the entire team to obtain information on the sizes and utility requirements of equipment that will be located in and moved around the final operational space, including any cleaning equipment. Examine where the connection points are located on the equipment (front, back, side). Are they coordinated with the utility connection points in the cleanroom space? This will help eliminate rework after the space is complete.

4. Review path of travel: Is equipment to be installed too high to clear doorways or have adequate clearance under overhead utilities, including allowances for dimensions of lifting equipment? Dragging heavy equipment across new flooring can damage it and take substantial time to repair rips or tears. Include these height and width limitations in any procurement documentation for elements that must be moved into the space during initial construction or later during the operational lifecycle of the cleanroom.

It is time-consuming and therefore expensive to disassemble and reassemble equipment that was shipped as one piece that must be dismantled to make clearances. Disassembly and reassembly projects also require specialized workers that add to the budget and strain the timeline. Be very clear if equipment or utilities must be broken into components to be moved in to the space. Virtual design tools can be beneficial if used to simulate the transit and installation in sequence. If it is not possible to complete a virtual run, a full-size model of the equipment can be fabricated and moved through the space.

5. Use BIM to avoid fabrication problems: Building Information Modeling (BIM) software will quickly resolve issues that could impose costly delays. It also helps better integrate project delivery by bringing in the installers early in the process and minimizing design conflicts. Bringing in mechanical, electrical and plumbing (MEP) subcontractors and structural subs early so that clashes can be identified before the installation begins saves time and money. Some things that “fit” on paper do not fit when the assembly requirements are considered. BIM is a great tool for detailing, fabrication and installation. For example, equipment with moving parts, panel clearances, code clearances, operational considerations—such as removing tubes of a heat exchanger during maintenance—can be shaded in as “no fly zones” during detailing. During construction, the BIM software model can be downloaded to laptop computers to be used by field personnel to install pipes, conduits and the HVAC.

6. Prefab for efficient construction: Prefabricate all applicable elements as much as possible to save time and to remove the process from the congested construction floor area. Prefab allows more teams to build components offsite simultaneously that would require sequential construction in the field due to floor space constraints. Prefab also allows for use of more automated tools that are often available in shops but not in the field. In addition, prefabrication minimizes the required lay down area within the constraints of the cleanroom footprint during the build-time period, thereby easing congestion. Cleanroom elements should be modeled in addition to MEP scope. 

7. Consider operations and maintenance: Make sure to consider serviceability of the equipment when planning out layout and the size of the spaces. Also talk to the maintenance team and operators to determine how they will service and use this piece of equipment. There is nothing worse than having a piece of equipment installed and operational that can’t be operated or serviced. Secondly, focus on layout approval from the user, builder and architect in regards to the location of the windows, doors and utilities.

8. Review cleanroom specified requirements: Confirm that user requirement specifications for the HVAC system are within manufacturing requirements. If the base system does not support the cleanroom requirements, performance criteria will not be met. 

9. Consider value engineering requirements: Be very careful during the value engineering phase of a project to ensure that key elements of the utilities are not cut back in a vain attempt to save money. The result can be that utilities don’t support the electrical and mechanical loads of the cleanroom.

10. Understand building utilities compatibilities. Confirm early in the process that new, additional HVAC demand is covered with existing building utilities and loads. It is wise to engage an engineering consultant to complete a full utility survey of the building prior to design and equipment purchase. There is nothing more costly than to find out at project completion that an existing air compressor is not capable of delivering at the capacity advertised. 

11. Check pressure differentials: Confirm that pressure differential is workable within existing space. Think through how your commissioning team would use the entire space, including existing space. Document the agreed-upon steps and obtain consensus from all impacted parties in existing spaces.

12. Ensure cleaning solution compatibility: Make sure that panels inside a room will hold up to sometimes caustic cleaning solutions. Also explore the compatibility of cleaning solutions suggested for floors and for wall panels. If the cleaning solution from walls drips on the floor, it could damage the floor. On occasion, cleaning solutions specified for floor and wall products are incompatible.

13. Guarantee materials compatibility: During design, confirm what type of floor will be installed and make sure floor type is compatible with wall material, including constructability details at connections points between the floor, walls and ceiling.  Clarify warranty exposures for connection details.

14. Mock up . . . and mock up again: Better meet client expectations on caulk joints by creating a mock-up that illustrates the seismic joint. Obtain buy-in from all parties on the mock-up. Make multiple copies of it for the architect, owner and contractor, then retain mock samples for comparison to installation. Make sure the mock-up shows the floor, base, ceiling wall, door frame and window frame materials. This allows you to test all the cleaning solutions and show how the space will look when completed.

15. Coordinate equipment pass-through: Understand the flow of anything that passes from one class of cleanroom to another. There should be no moving parts moving between different classes of cleanrooms. 

16. Check bioseals: Make sure all bioseals are installed at changes in pressures and class.  Confirm during design review and also during commissioning.

17. Include plenum equipment: Review often-overlooked plenum equipment. All equipment mounted in plenum must be cleanable and comprised of equal materials.   Also think about the delivery date of plenum equipment. It should arrive after the walls are built, but prior to installation of the ceiling above the plenum.

18. Properly sequence leak test: Confirm that the subcontractor has completed the leak test on panels prior to air balance. If done out of sequence, you will lose time and money when you have to repeat air balances of these critical facilities on deadline.

19. Coordinate structural with cleanroom architecture: The layout between structural and architectural is crucial. This step is often overlooked. Without this back check, you can have a zero tolerance between the structural framework of the cleanroom and the architectural walls. Doors and windows must be coordinated with existing columns and building elements. About the AuthorsMelody Spradlin, a former Genentech senior manager for project engineering, is the leader of Dome Construction Corporation’s San Jose office. She can be reached at: [email protected]. Lisa Rose is an MEP specialist with extensive cleanroom construction experience.
About the Author

Melody Spradlin and Lisa Rose | Dome Construction Corporation