1.0 PURPOSE:
    
    To  describe  a  standard operating procedure for   Cleaning  /  Replacing the  filters of HVAC system of pharma area.
    
2.0    SCOPE:
    
     The Standard operating procedure describes in detail the method  of Cleaning / Replacing the filters of HVAC system of pharma area.
    
3.0    RESPONSIBILITY:
    
    The responsibility  of  cleaning / replacing the  filters as per the  standard operating procedure lies with the staff of rank not  lower  than  junior utility operator under the supervision  of  supervisor.
        
The  responsibility of preparing, reviewing  and approving  the  standard  operating  procedure lies with the  Manager  -  Maintenance, Head of Production and Head of QAD respectively.

4.0    METHOD:

4.1    Check the pressure difference across the filters daily and record same in the register as shown in the Annexure-I.

4.2    Filter Checking:

4.2.1    20 Micron Filter:

4.2.1.1    If the pressure difference is more than 6 mm of wgp clean the filter.

4.2.1.2    Clean the filter with air pressure at 1 Kg/cm2 and wash with water jet. Using air jet clean non-dust laiden face of the filter (reverse direction of air flow in system) and then from the other side.

4.2.1.3    Allow the filters to dry with air jet before reinstallation.

4.2.1.4    Install the filters and check the pressure difference.  Record the cleaning data in the register as per Annexure-II.

4.2.1.5    If the pressure difference is less than 2 mm of wgp check the flange leak and visual test of the filters, incase of puncture replace the filter.

4.2.1.6    If the pressure difference is more than 6 mm of wgp even after cleaning replace the filter with a new one and record the same in the register Annexure-III.

4.2.1.7    Frequency : Once in a week or whenever the pressure difference is more than 6 mm of wgp whichever is earlier.

4.2.2    10 Micron Filter:

4.2.2.1    If the pressure difference is more than 10 mm of wgp clean the filter.

4.2.2.2    Clean the filter with air pressure at 1 Kg/cm2 and wash with water jet. Using air jet clean non-dust laiden face of the filter (reverse direction of air flow in system) and then from the other side.

4.2.2.3    Allow the filters to dry with air jet before reinstallation.

    
4.2.2.4    Install the filters and check the pressure difference.  Record the cleaning data in the register as per Annexure-II.

4.2.2.5    If the pressure difference is less than 4 mm of wgp check the flange leak and visual test of the filters, incase of puncture replace the filter.

4.2.2.6    If the pressure difference is more than 10 mm of wgp even after cleaning replace the filter with a new one and record the same in the register Annexure-III.

4.2.2.7    Frequency : Once in a week or whenever the pressure difference is more than 10 mm of wgp whichever is earlier.

4.2.3    5 Micron Filter:

4.2.3.1    If the pressure difference is more than 12 mm of wgp clean the filter.

4.2.3.2    Clean the filter with air pressure at 1 Kg/cm2 and wash with water jet. Using air jet clean non-dust laiden face of the filter (reverse direction of air flow in system) and then from the other side.

4.2.3.3    Install the filters and check the pressure difference.  Record the cleaning data in the register as per Annexure-II.

4.2.3.4    If the pressure difference is less than 5 mm of wgp check the flange leak and visual test of the filters, incase of puncture replace the filter.

4.2.3.5    If the pressure difference is more than 12 mm of wgp even after cleaning replace the filter with a new one and record the same in the register Annexure-III.

    
4.2.3.6    Frequency : Once in a week or whenever the pressure difference is more than 12 mm of wgp whichever is earlier.

4.2.4    2  Micron Filters:

4.2.4.1    If the pressure difference is more than 12 mm of wgp clean the filter.

4.2.4.2    Clean the filter with air pressure at 1 Kg/cm2 and wash with water jet. Using air jet clean non-dust laiden face of the filter (reverse direction of air flow in system) and then from the other side.

4.2.4.3    Install the filters and check the pressure difference.  Record the cleaning data in the register as per Annexure-II.

4.2.4.4    If the pressure difference is less than 5 mm of wgp check the flange leak and visual test of the filters, incase of puncture replace the filter.

4.2.4.5    If the pressure difference is more than 14 mm of wgp even after cleaning replace the filter with a new one and record the same in the register Annexure-III.

4.2.4.6    Frequency : Once in a week or whenever the pressure difference is more than 12 mm of wgp whichever is earlier.

4.2.5    0.3 Micron Hepa Filters:

4.2.5.1    If the pressure difference is more than 30 mm of wgp check the air flow, check the condition of the prefilters.  If the pressure drop is more than 30 mm of wgp at all satisfactory conditions replace the filter with new and record the same in the register Annexure-III.

4.2.5.2    If the pressure difference is less than 15 mm of wgp check the flange leakage and puncture.  In case of puncture, replace the filter with new.

4.3    Filters cleaning status tag shall be displayed as follows.

4.4    Apart from the above cleaning frequency the filters shall be cleaned whenever the Engineering requisition comes from the user department that the room pressures are not maintained as per the specification.

4.5    Exhaust Grills/Filters shall be cleaned whenever there is product charge in the pharma area.
    
5.0    RECORDING:

    The responsibility of recording the cleaning and changing of filters in air handling system of pharma area lies with the staff of rank not lower than the supervisor of maintenance department as shown in Annexure-I, Annexure-II & Annexure-III.

Cleaning, filters of hvac, engineering