In clean room design we establish and maintain an environment with a low level of environmental contaminants such as dust, airborne microbes, aerosol particles and chemical vapors. Designing such a sensitive environment as the clean room is not an easy thing, but the following 10 steps definitely help you and define the easy way to design it.
Most clean room manufacturing processes required the extremely stringent conditions provided by the clean room. Clean room design in every proper orderly form is very important, as clean rooms have complex mechanical structures and high development, running and energy costs. The steps below present cleanroom evaluation and design methods, people/material flow in factories, space cleanliness classification, space pressurization, space supply airflow, space air exfiltration, balance of space air, variables to be evaluated, mechanical system selection, heating/cooling load calculations, and support space requirements.
1. People/Material Flow Assessment Design:
It is essential to assess the flow of material and people within the clean room. All critical processes should be isolated from personnel doors and pathways, this helps clean room workers because they are the largest source of contamination in a clean room.
There should be a strategy for critical spaces that, compared to less critical spaces, more critical spaces should have only one access to prevent the space from being a path to others. Some pharmaceutical and biopharmaceutical processes are susceptible to cross-contamination from other pharmaceutical and biopharmaceutical processes. For process isolation of materials, raw material entry and containment routes, and finished product exit and containment routes, process cross-contamination must be carefully evaluated.
two. to identify classification for space cleaning:
It is very important to know the primary cleanroom classification standard and what the particulate performance requirements are for each cleanliness classification at the time of selection. It is very important to know the primary cleanroom classification standard and what the particulate performance requirements are for each cleanliness classification at the time of selection. There are different cleanliness classifications (1, 10, 100, 1,000, 10,000, and 100,000) and the allowable number of particles in different particle sizes provided by the Institute of Environmental Science and Technology (IEST) Standard 14644-1.
3. to identify Pressurization for Space:
Maintaining a positive air gap pressure, along with dirtier clean order gaps, is critical to preventing contaminants from invading a clean room. It is extremely difficult to reliably maintain the cleaning order of a space when you have unbiased or negative space pressurization. What should be the spatial weight differential between spaces? Different tests evaluated the penetration of contaminants in a clean room versus the spatial weight differential between the clean room and the uncontrolled connection condition. These tests found that a weight difference of 0.03 to 0.05 wg was feasible to decrease contaminant invasion. Spatial weight differentials of more than 0.05 in. wg try not to give contaminant penetration control considerably better than 0.05 in. workgroup
Four. to identify Space Supply Airflow:
The cleanliness rating of the space is the primary variable in determining the supply airflow of a clean room. Looking at Table 3, each clean classification has an air change rate. For example, a Class 100,000 clean room has a range of 15 to 30 ach. The cleanroom air exchange rate must take into account the anticipated activity within the cleanroom. A Class 100,000 (ISO 8) clean room that has a low occupancy rate, low particulate generation process, and positive space pressurization relative to adjacent dirtier clean spaces might use 15 ach, while the same room clean with high occupancy, frequent in/out traffic, high The particulate generation process or neutral space pressurization will likely need 30 ach.
5. to identify Space air exfiltration flow:
Most cleanrooms are under positive weight, causing organized air leakage into connecting spaces that have lower static weight and improvised air leakage through electrical outlets, lighting fixtures, window surrounds , entrance outlines, wall/floor interface, wall/ceiling interface and access entrances. It is essential to understand that rooms are not hermetically sealed and have spills. A full fixed clean room will have a volume spill rate of 1% to 2%. Is this spill terrible? Not really.
6. to identify Space Air Balance:
Most cleanrooms are under positive weight, causing organized air leakage into connecting spaces that have lower static weight and improvised air leakage through electrical outlets, lighting fixtures, window surrounds , entrance outlines, wall/floor interface, wall/ceiling interface and access entrances. It is essential to understand that rooms are not hermetically sealed and have spills. Each fixed clean room will have a volume spill rate of 1% to 2%. Is this spill terrible? Not really.
7. Evaluate the remaining variables:
The different factors waiting to be evaluated include:
Temperature: Clean room specialists wear bunny dresses or full suits over their normal clothing to decrease particulate age and potential contamination. Due to their additional garments, it is important to maintain a lower room temperature for the comfort of the practitioner. A space temperature that extends somewhere in the range of 66°F and 70° will give comfortable conditions.
Humidity: Due to the strong wind current in a clean room, a large electrostatic charge is created. When the ceiling and walls have a high electrostatic charge and the space has a low relative humidity, particles in the air will attach to the surface. When the relative humidity of the space expands, the electrostatic charge is released and all trapped particles are discharged in a short period of time, causing the clean room to fall apart. Having a high electrostatic charge can also damage delicate electrostatic release materials. It is important to keep the relative humidity of the space high enough to reduce the build-up of electrostatic energy. An RH or 45% +5% is considered the ideal tack level.
Laminarity: Very basic procedures may require a laminar flow to decrease the amount of contaminants entering the airstream between the HEPA channel and the procedure. IEST standard #IEST-WG-CC006 provides wind current laminarity requirements.
Electrostatic discharge: Beyond space humidification, some procedures are extremely sensitive to electrostatic discharge damage and it is important to introduce a grounded conductive platform.
Vibration and noise levels: Some precision forms are exceptionally sensitive to clamor and vibration.
8. Mechanical system design identification:
Several factors influence the design of the mechanical framework of a clean room: space accessibility, affordable subsidies, process needs, cleaning arrangement, required consistent quality, energy cost, construction standards, and neighborhood atmosphere. Unlike typical air conditioning frames, clean room air conditioning frames have much more supply air than expected to meet cooling and heating loads.
Class 100,000 (ISO 8) and lower class 10,000 (ISO 7) clean rooms can have the full AHU air experience. Taking a look at Figure 3, incoming air and outside air are mixed, separated, cooled, heated, and humidified before being sent to HEPA terminal channels in the ceiling. To prevent contaminant distribution in the clean room, incoming air is obtained through low split returns. For cleanrooms above class 10,000 (ISO 7) and cleaner, the wind currents are too high for all the air to experience the AHU. Taking a look at Figure 4, a small part of the arriving air is sent back to the AHU for shaping. The rest of the air returns to the field fan.
9. Perform cooling/heating calculations:
When performing cleanroom heating/cooling calculations, consider the following:
Use the most moderate atmospheric conditions (99.6% heating plan, 0.4% dry bulb/medium wet bulb, and 0.4% dry/wet bulb cooling scheme information).
- Incorporate the filtration in the figures.
- Incorporates humidifying complex heat in figures.
- Incorporate the process stack into the figures.
- Incorporate heat from the distribution fan into the estimates.
10. Space fight in the engine room
Clean rooms are mechanically and electrically concentrated. As the order layout of the clean room becomes cleaner, more mechanical structure space is expected to provide satisfactory help to the clean room. Using a 1,000 square foot cleanroom, for example, a Class 100,000 (ISO 8) cleanroom will require 250 to 400 square feet of ancillary space, a Class 10,000 (ISO 7) cleanroom will require 250 to 750 square feet. square feet of ancillary space, a Class 1000 (ISO 6) cleanroom will require 500 to 1000 square feet of ancillary space, and a Class 100 (ISO 5) cleanroom will require 750 to 1500 square feet of ancillary space.
For Clean Room Design under experience, read also https://www.operonstrategist.com/clean-room-design-consultant/