How to Plan a Cleanroom Design & Build Project

March 17, 2020

Guide & Considerations

AdvanceTEC starts with your process requirements and your business objectives. We then design and construct your cleanroom- based on your budget- from that foundation. Our in-house engineering, design, construction management and project management teams enable us to bring constructability and tool requirements into the cleanroom design flow.

  • All elements of the cleanroom project typically developed by project designer
  • Plan should define the design & construction related requirements for products and processes specified by user and facility management
  • Cleanroom project team- establish goals, objectives, needs of the project, project scope, technical performance requirements, outline schedule & budget, identify project responsibility
  • List of staff-building, environmental, safety, code regulations, good manufacturer practice guidelines
  • Consider cost of impact, schedule of design process, milestones
  • Risks need to be identified & mitigations planned

Cleanroom Contamination Control Considerations
  • All equipment & processes used in cleanroom should be in a matrix listing requirement
  • Additional issues that affect the building design and construct ability
  • Hierarchy of cleanliness should be specified & contamination control concept should be developed
  • Contaminant movement & mitigation need to be analyzed

Cleanroom Site Selection & Services Requirement
  • Ground load-bearing capacity
  • Ground water and soil toxicity
  • Ambient air quality & airborne pollutants
  • Availability of utility and services at site versus the required utility and services to determine if additional services or remote connections from adjacent facilities
  • Environmental issues
  • Site ambient vibration & noise levels determination of their acceptability for the process with or without special treatments
  • Ambient electromagnetic fields
  • Local zoning ordinances & regulation

Cleanroom Critical Flow Arrangements
  • Operations, maintenances and quality personnel need to be consulted throughout the design
  • Efficient operation- a systemic design effort to determine functional interdependences adjacencies & efficient flow to minimize the migration of contaminants and to optimize process flow
  • Design of personnel flow in and out of cleanroom
  • Equipment and materials entering cleanroom must be precleaned and moved through either an airlock or a pass through
  • Exposed room surface finish materials must be compatible with the processes in the cleanroom

Cleanroom Planning Guide – Checklist

Cleanroom Facility Design Considerations
  • Standard-ISO 14644-1
  • The class of airborne particle concentration is specified
  • Levels of other cleanliness attributes
  • Facility Planning- externally -> environment & community
  • Climate, geology, topography, building codes, height, color
  • Architectural Planning- internally driven -> engineer requirements, user requirements, quality requirements, corporate standards
  • Predesign & Design Activities
  • Project profile development
  • Expandability
  • Flexibility
  • Adequacy of space
  • Minimization of classified environments
  • Impacts to site/environment/community
  • Cleaning methods & materials
  • Cleanability and accessibility
  • Construction Methods
  • Standard construction
  • Prefabricated construction
  • Cleanroom construction materials
  • More monolithic, nonporous, non-shedding, easily clean
  • Pressurization-door seals->direction of swing
  • Vibration-internal/external
  • Constructability

General Indoor Design Conditions & Considerations
  • Temperature
  • Personnel considerations
  • Process-related conditions
  • Construction materials and temperature specification
  • Monitor and control
  • Humidity
  • Process equipment can add moisture
  • Exhaust
  • Replacement air should be conditioned before entering the cleanroom
  • The greater amount of outdoor air introduced, the higher the cost of conditioning
  • Airborne Molecular Contamination
  • Makeup Air
  • Air handling units (AHU) requires series of filters to remove particles from ambient air
  • Filters protect the coils & extend life of HEPA/ULPA filters
  • Process Exhaust
  • Filtration System-HEPA/ULPA filters typically mounted to ceiling

Indoor Environmental Quality
  • Air temperatures, humidity, supply air distribution speed

Outdoor Emission Control & Outdoor Air Intake
  • Release of particles, chemical fumes, or microbes

Design for Safety Concerns
  • Physical barriers & zone separation to reduce the impact of sudden dispersion
  • Zone-or room-based air purge system
  • Storage of toxic/flammable material
  • Proper egress path design to reduce the exit distance
  • Isolation of hazardous materials
  • Code requirements

Security & Access Control- Protect against unauthorized personnel
Building Codes & Standards- Authority having jurisdiction, international codes, national local codes/standards, OSHA, ADA, EPA, NEC

Cleanroom Testing Terminology
  • Airborne Molecular Contamination-AMC
  • Coincidence-presence of 2 or more particles
  • Colony-forming unit (CFU)
  • Condensation nucleus Counter (CNC)
  • Diluter
  • Functional requirement specification (FRS)
  • Macroparticle
  • Master plan
  • National Metrology Institute (NMI)
  • Particle Size Cutoff Device
  • Polydisperse Aerosol
  • Ultrafire Particle
  • Viable Particle

Cleanrooms in Semiconductor & Electronic Facilities
  • Facilities need to be flexible, environmentally benign, extendable, reliable and cost-effective
  • Wafer & chip are terms used to describe the base manufacturing units
  • Wafer-refers to mono-crystalline silicone dishes used to produce integrated circuit devices
  • Wafers & chips are produced in a fabrication facility or “wafer fab” or “fab”

HVAC Configuration Cleanroom
  • Meet heating & cooling needs- satisfies space air cleanliness requirements with that same system
  • Traditionally accomplished air cleanliness- by using high airflow rates
  • Challenge is to configure system when airflow rate required by dilution is higher than required heating & cooling load
  • A cleaner class cleanroom requires higher airflow rate
  • ACH= air changes per hour
  • Engineers first calculate airflow rate required to meet heating/cooling load
  • Then calculate airflow rate to achieve air cleanliness
  • Then use flow ratio to determine best practices
  • Airflow streams can either be mixed, diverted or both

HVAC Design for Various types of Pharma Facilities
  • Primary means of protection from cross-contamination
  • Pharma products in two categories:
  • Nonsterile Products-tablets, capsules, liquids, creams & ointments & medical devices noninvasive
  • Sterile Products-injected into blood stream by syringe or intravenous catheter, medical devices that are inserted into body
  • Two Basic Ingredients:
  • Inactive ingredients
  • Active ingredients

Clean Design
  • Interior surfaces & fitted air delivery systems have some impact on air cleanliness
  • For better HVAC
  • Corrosion-resistant interior surfaces
  • Direct-drive instead of belt-driven fan motors
  • Sealed bearings for motors
  • Ultraviolet (UV) lights for cooling coils
  • Antimicrobial coating on cooling coil drain pans

Design for Redundancy & Reliability
  • Redundancy should be provided at level matches process requirements
  • Addressed at a component level, multiple fans operating in tandem (fan wall), or at system level with multiple air handlers in parallel operation

Cleanroom Airflow Rate
  • Cleanroom height can impact air change rate and air velocity

Cost-Effective Options for Lowering Cleanroom Air Change Rates
  • More options are available than using a high air change rate
  • Some measures can be used to lower the air change rate requirement
  • Selecting equipment, machinery, furniture, and room construction materials with lower particle generation levels
  • Pick lowest particle generation as possible
  • Isolate and remove High-Concentration Particles generated in the cleanroom
  • Enhance surface cleaning protocols to prevent surface particles from turning into airborne particles
  • Control particle entry through supply air
  • Design return and exhaust air systems effectively for particle exit
  • Maintain proper pressurization/no depressurization

Bryan Phelan
Managing Partner, Director of Customers

As managing partner, Phelan is responsible for ensuring client satisfaction, shaping the company’s strategic direction, and managing all compliance aspects of the organization.

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