Objective for URS of AHU :
This document is generating for the purpose of specifying the URS of AHU (Air handling unit). The objective of this document is to provide the requirement and appropriate design to support the prospective supplier to identify company needs, price quote for the Heating, ventilation and air conditioning system (HVAC) and performance requirements for procurement of HVAC system including major ancillary component or fabrication of the area so as to meet the in-house requirements as well as compliance with cGMP. The URS of AHU is also provided to the Supplier to provide a price quote for the supply for air handling unit including the design, Performance and manufacture of the equipment.
Table of Content for URS of AHU:
| Description |
| Title page |
| Objective |
| Table of contents |
| Approval of Documents |
| Scope |
| Location of equipment |
| Communication |
| Applicable codes and standard |
| System/equipment/instruments details |
| Scope of supply |
| Brief system description |
| Technical specification |
| Safety features |
| List of Abbreviations |
Approval of Documents for URS of AHU:
Prepared by:-
| Name | Designation/Department | Signature | Date |
| Executive/ QA |
Reviewed by:-
| Name | Designation/Department | Signature | Date |
| Manager/Production | |||
| Manager/Engineering |
Approved by:-
| Name | Designation/Department | Signature | Date |
| Manager/QA |
Scope:
The scope of this document is to define the requirements of the air handling unit in facility.
Location of equipment:
Machine will be installed in service area
References
Reference has been taken from the existing equipment and from the internet or vendor brochure
System/equipment/Instruments details for URS of AHU:
| Name of the equipment | Air Handling Unit |
| Model/Type | As per cGMP model |
| Capacity | As per requirement |
Scope of Supply:
| Type of Device | Air handling unit |
| Machine Standard | The current state of the art GMP Compliance. European medicine agency (EMA) and WHO, Regulations compliance. |
| Machine design standard for safety | ISO 13852:1996 safety of machinery -safety distance to prevent danger zones being reached by upper limbs.ISO 13853:1996 safety of machinery safety distance to prevent danger zones being reached by lower limbs |
| Features | Design conforming to cGMP standardsSimple and Convenient operation, , Cleanliness, Operator protection and Ease to maintenance.Easy cleaning designed with easy removal weight adjustment sector.AC Frequency drive for motor |
| Document & Certificate | Manuals and Maintenance Instructions Operator manualInstallation and assembly instructions for all devices.User’s manuals for all components.Trouble shooting guide.Maintenance Manual.Safety instruction.Training documentation. Electrical and Control diagrams Single line drawing for electrical distribution.Circuit diagramsCable list.Equipment location drawing for electrical equipment and instruments. |
| Qualification Protocols | DQ Protocols and reports.FAT protocol and report.SAT protocol and reportIQ protocol and reportOQ Protocol and reportVendor should organize for Execution of IQ/OQ and support for PQ |
| Training | Vendor should impart necessary Operational training to user department and maintenance training to maintenance department. |
| Test ,Calibration, MOC Certification | All test certificate for brought items will be provides during FAT with FAT DocumentsMOC Certificate will be providing during FAT with FAT documentsCalibration certificate provide for gauge during FAT. |
Brief system description:
- Air handling unit is sometimes abbreviated as “AHU.” As the name implies, an air handling unit is a piece of equipment that handles air. Its internal structure is very simple. The air handling unit (AHU) is the heart of central air conditioning. It collects outside air and room air, removes dust and other particles from the collected air, adjusts the temperature and humidity and then supplies comfortable and refreshing air-conditioned air into the rooms through ducts.
- Air handling unit is a huge indoor unit of commercial air conditioning equipment. This massive “indoor unit” is installed on a rooftop or along an external building wall. It produces cool/warm air and sends it to the rooms for cooling/heating. Unlike ordinary commercial air conditioners, air handling units are usually made to order for individual buildings. Furthermore, air handling units can be customized by internally mounting a filter, humidifier and other devices for the control of temperature, humidity, air flow and air cleanliness.
The basic construction of the machine consists of :
| Parameter | Specification |
| AHU Panel Sheet | Galvanized iron |
| Process blower | Mild Steel |
| Ducting | Galvanized iron |
| Damper | Aluminium |
| Condensate collector tray | SS-304 |
| Control panel | GI-with powder coated/ pre-wired electrical |
| Surface of air contact part | There should be no welding burrs.Surface should be smooth without crevices. All joints should be finished with silicon sealant and there should not be any gap for dust accumulating in the joints. |
The Drive:
The machine is equipped with frequency controlled drive. A large torque can be achieved even at low speed and because of its high regulating speed. The is centrally driven by an electric motor.
Grill/ Air Intake Screen
On the front of every AHU is a grill (or Air Intake Screen) to prevent large, unwanted objects from entering the system and potentially causing damage or a blockage.
Damper
The first internal component of any AHU is the damper. This is multiple sheets of rotating metal that are used to adjust the volume of air entering the AHU. They can open and close fully and also open partially. As well as controlling the volume of air, dampers are important when it comes to preventing the spread of fire, closing to act as a fireproof break two sides.
Filters
Having passed through the frost protection coil, the air then passes through a filter. This removes any small dust and dirt particles that, if allowed to enter the system further, would damage the components and would also result in people breathing in contaminated air. There are two types of filter – panel filter and bag filter
Mixing Box
A mixing box helps increase the energy efficiency of an AHU by recirculating returning air from the ductwork (from the zones/rooms) and mixing it with fresh air being introduced from outside. The heat from the returning air is used to heat the outside air, thereby reducing the energy output required from the AHU itself.
Cooling & Heating Coils
These set the temperature that leaves the AHU. A thermostat is used to ascertain the temperature of the air in the AHU. If the air is deemed too hot, the heating coil will be activated and vice versa. This desired temperature is known as the Set Point.
Supply Fan
The fan circulates the air from the AHU, into the ductwork, along to the various zones. It pulls the air into itself and then propels it out. The speed at which the air leaves the fan can be controlled. Historically these were centrifugal fans but for increased efficiency they are now EC (Electronically Communicated) fans .Fans has a pressure sensor to ensure they are running and functioning correctly.
Secondary Filter
A secondary filter further filters the air in the AHU before it leaves and continues its journey through the ductwork.
Dehumidifier
Depending on the geographic location and requirements of the building, some AHUs also have a humidifier (and humidity sensor). The sensor measures the level of moisture in the air, should the level need to be controlled. A humidifier is usually one of the last components in an AHU and if deemed unnecessary, they may be turned off to increase efficiency.
Control Panel
Every AHU will have a control panel, featuring individual switches and run and trip indicators for the fan and heater. There are three different types of control panel: single stage control panel, 3 step control panel and 6 step control panel, referring to the number of steps of heater control.
Electrical chamber and mechanical chamber:
All mechanical components such as gears, motors, and moving belts, as well as electrical components such as wiring, switches, and MCBs, are installed in this segment.
Technical Specification for URS of AHU:
| Particulars | Specification |
| Model/Type | As per cGMP model |
| Capacity | As per requirement |
| Speed Available | As per requirement |
| Overall dimension (mm) | As per requirement |
| VFD | As per motor rating |
| Design | Double skinned Outer skin (CRC powder coated)CFM- as per designed |
| Blower | As per required CFM |
| No. of air changes per hour in cubicle | Should be NLT20 Nos./ Hour for the Class of area ISO 8 at rest condition. |
| Particulate matter count | Should meet the specifications of Class / Grade: Class ISO 8 / Grade D area. |
| Microbial load | Should meet the specifications of Class ISO 8 / Grade D |
| Recovery / Clean up period | Should be achieved within 15 minutes |
| Recovery for temperature and RH | Should be achieved within 30 minutes |
| Air flow pattern | The smoke should be diffused uniformly at supply air location to room and pass through return location Also smoke should be passed from positive pressure area to negative pressure area. |
| Filter detail | Fresh Air Filter: Efficiency: 90% (10m)Pre filter: Efficiency: 90% 10m Description: EU–4 Fine Filter: Efficiency: 99% 5m Description: EU-9 HEPA Filter: Efficiency: 99.997% 0.3m Description: EU-13PAO Testing port should be provided for installed HEPA filter leak test and installed HEPA filter should be leak tested at siteAccess port / Door should be provided to allow HEPA filter integrity test on site. |
| Electrical motor for main supply blower | Type: 3 Phase induction motor. Motor should be compatible to run with VFD Motor should be Flame proof. |
| Coil | As per design |
| Ducting | Return air ducting Supply air ducting All duct joints should be filled with gasket & sealant for zero leakagesVolume control dampers should be used for the better air control Neoprene rubber gasket should be used between duct joints.Velocity sensor port should be provided in supply duct.Individual damper for each supply and return of the room side should be provided. |
| Duct leakages | Should be less than 3 % of total volume handled by system. |
| Operational feature | AHU cum dehumidifier should be operational through Auto / Manual switch and also compatible to run with VFD |
| Fresh air | Minimum 10% |
| Heater | As per design/requirement (flameproof) |
| Filter section | All the filter banks, blower section, coil section should be facilitate with the provision for the measurement of the differential pressure across the filters. |
| Damper section | Low leakage aerofoil dampers should be provided.Individual damper should be provided for supply, return, fresh air, relief air, reactivation air etc.All dampers should have positive locking arrangement. |
| Desiccant wheel | As per design/requirement |
| Machine Mounting | It should be 04 nos Anti vibration pad with 100/150 mm distance piece. |
| Electric panel | Electrical panel with push button and digital indicator.Emergency Switch.On/ off switchElectric panel with MCB, contactor, overload relay, controls relay, VFD. |
| Performance of the system according to operation. | The system is intended to be operated regularly 24 hours, 7 days per week. |
| Identification | Details of Make, Name, Serial. No., Capacity, Model and Year of manufacture should be available |
Safety Features for URS of AHU:
| Critical Variables | Acceptance Criteria | Reference |
| MCB | MCB is provided so that when there is an overload in current or any short circuit then the MCB trips. | Safety Requirement |
| Mechanical Guard | Mechanical guard for all rotating parts. | Safety Requirement |
| Joints | Welding of joints without any welding burrs. | Safety Requirement |
| Metal Parts | All the metal parts should be properly grounded without any sharp Edges. | Safety Requirement |
| Leveling and Balancing | Equipment should be properly balanced & leveled. | Safety Requirement |
| Installation | All the Installation must be in accordance with the cGMP. | Safety Requirement |
| View lamp and view window | FLP / NFLP view lamp should be provided in blower section with view glass on panel. | Safety Requirement |
| Alarm system | Alarm should be provided. | Safety Requirement |
| Electrical Wiring And Earthing | Electrical wiring should be as per approved drawings. Double external Earthing to control machine (panel and motors) and operator should be provided. | Safety Requirement |
| Noise Level | Below 80 db. | Safety Requirement |
| Emergency/Safety Switch | Provided easy access position | Safety Requirement |
Spare parts / Change parts
Vendor should provide Preventive Maintenance SOP, List of recommended critical spare parts with code no. considering 2 years of satisfactory working of machine. After Sale Service/ AMC for the machine should be provided after warranty period. Vendor should provide all spares required for 2 years of use at the time of shipment.