Purified water system validation

     

Purified Water system validation

water system validation shall be done in three phases.

Phase -1

Phase -2

Phase -3

Phase -1

A test period of 2-4 weeks should be spent for monitoring the system intensively. During this period the system should operate continuously without failure or performance deviation.Water cannot be used for pharmaceutical manufacturing in this phase.The following should be included in testing approach.

·       Under take chemical & microbiological testing in accordance with a defined plan.

·       Sample incoming feed water daily to verify its quality.

·       Sample each step of purification process daily.

·       Sample each point of use daily.

·       Develop appropriate operating ranges.

·       Demonstrate production and delivery of product water of required quantity and quality.

·       Use and refine the SOP’s for operation,maintenance,sanitization and trouble shooting.

·       Verify provisional alert and action levels.

·       Develop and refine test failure procedure.

Phase -2

A further test period of 2-4 weeks. Sampling scheme will be same as  Phase – 1.Water can be used for manufacturing process in this phase.

Approach should also

·       Demonstrate consistent operation within established ranges.

·       Demonstrate consistent production & delivery of water of required quality and quantity.

Phase - 3

Phase 3 runs for one year after satisfactory completion of phase-2.Water can be used for manufacturing process during this process.

Objectives & Features of Phase -3

·       Demonstrate extensive reliable performance.

·       Ensure that seasonal variations are evaluated.

·       The sample locations, sampling frequencies and test should be reduced to the normal routine pattern based on established procedures proven during Phase -1 & phase - 2.

Specification :

Test	Specification
Description	A clear colourless odourless liquid.
pH	Between 5.0 and 7.0.
Conductivity	Stage-1: Not more than 1.3 µS/cm (online).                             ( or) Stage-2: Not more than 2.1 µS/cm(off-line). Stage-3: If the conductivity result is greater than 2.1 µS/cm, then proceed as in table - pH and conductivity requirements.
Total Organic Carbon	Not more than 500 ppb
Nitrates	Not more than 0.2 ppm
Heavy Metals	Not more than 0.l ppm
Total Aerobic Microbial  Count	Not more than 100 CFU/mL
Specified Pathogens
Test for Escherichia coli	Shall be absent.
Test for Salmonella species	Shall be absent.
Test for Staphylococcus aureus	Shall be absent.
Pseudomonas aeruginosa	Shall be absent.

Air handling unit (AHU) Qualilfication and Clean room classification

Air handling unit (AHU) Qualilfication  and clean room Classification : 

 Ensure the AHU is in switch ON.

 Switch ON the anemometer and allow it to some time for stabilization.

  Ensure that anemometer measuring unit is in FPM mode.

 To change the measuring unit mode, press the UNIT button till display shows FPM.

Take the readings at five locations at each filter as per below mentioned diagram.

           

V1                                    V2                      V5 V3                                    V4

•  Position the probe pointing towards airflow. Locate the probe approximately 1/6 diagonal distance and measure velocities from each corner.For clean room measurement shall be taken at a distance of 150 mm from the filter face. Take the readings after stabilization or take the average reading of oscillating value shown in the display.

Procedure to Calculate the Air changes

  Calculate the supply grill area A= Length (in ft) x Width (in ft).

Calculate the supply grill Average velocity V= (V1+V2+V3+V4+V5 ) /5.( in ft/min) .

Calculate the air flow delivered by each supply grill in CFM   = A x V (in CFM).

Find the total quantity of supply air delivered in to the room in CFM by adding all             supply grills air flow CFM.

Calculate the air changes by below given formula.

                    Air changes per hour = Total supply air flow rate (CFM) in the clean room x 60

                                                                        Volume of the clean room (cu. ft)          

Example :

Air velocity =  100 feet per min

Air Flow =  Velocity Ft/ min x grill area(Ft²⁾

                              =  100 x 4 =400 Cubic feet per min(CFM)

If room has two supply grills, sum the two air flows = 400+ 400= 800 CFM

Air changes = Air flow x 60

Room volume(Ft³ )

=800 Ft³x 60 min

  1000 Ft³

= 48 Air changes per hour (Limit : Not less than 25 air changes per hour for ISO 8)

There are 5 tests during AHU Qualification.

S.NO	Test	Frequency	Instruments used	Acceptance criteria
1	Air Changes	For every six months (on or before 7 days)	Anemometer for Velocity of air	Not less than 25 air changes per hour
2	Particle count “At Rest Condition”		Particle counter	Not more than 3520000 for ISO 8 There is an equation to estimate particle limit.
3	HEPA Filter Integrity Test (Leak Test)		Aerosol Photometer and Aerosol generator using compressed air	No leak should be observed Not more than 0.01% leak
4	Recovery test	For every one year (on or before 15 days)	Particle counter	Recovered within 15 minutes, after polluting the room with aerosols
5	Air flow pattern		Dry ice in hot water to generate SMOKE	Uni-directional and positive and negative pressure should be indicative.

Regards,
Bujji Reddy.
9676749937














     

Reference standard and working standard

Reference standard/Primary reference standard evaluation requirements.

Characterization shall be done.
The elements of characterization are 1)NMR  2)Mass 3)IR 4)UV 5)CHN analysis.

Impurities(all impurities) tests shall be done :
 Organic impurities, Water content, Loss on drying/Residual solvents.

Potency : 100- All impurities.

In this way the reference standards are qualified.
All pharmacopeial standards comes under this category. No further testing is required for the primary reference standards.


Working standard/Secondary standard :

Select one approved batch to qualify the working standard

Analyse the sample against Pharmacopoeial reference standard for the Assay test and quantify for the assay.

Identification by Infrared spectroscopy using reference standard shall be done.

Preparation and usage of standards are very important. the batch release depends on the standards effectiveness and accuracy.

Air velocity and air flow and Air changes of AHU system in clean room

Air velocity: 
Speed of air under unit time, the units here are feet per minute(FPM).

Air flow measured in Cubic feet per minute(CFM):

= Air velocity(Feet per min) x Supply grill area(ft square)
= the results is in CFM.

Air changes per hour :

=Air flow x 60/ Total room area(Cubic feet)
= this gives air changes per hour
Limit is not less than 20 Air changes per hour

Limit of qunatitation-Requirements

The Quantitation limit or Limit of quantitation in short LOQ:

LOQ is the least level of concentration of an analyte(eg: Impurity-A) That an analtyical method can quantify precisely and accurately.

How to estatblish LOQ :

Method 1: Slope and standard deviation(=Steyx in Microsoft excel) method.

Inject low concentrations of an analyte  from the detection level about 3-4 concentrations and record the absorbances.

X= Concentration(% of impurity with respect to test sample concentration)

Y= Absorbances.

Now calculate slope and Standard deviation(SD) using Microsoft excel.

% LOQ = 10 x Slope/ SD

Method 2: Signal  to noise ratio method.

Prepare the analyte about 0.1% level and find the S/N ratio of the peak.

now estimate the concentration to get the  analyte peak signal to noise ratio is about 10:1

Inject the concentration to check the S/N is about 10:1

Now the estimated concentration is called LOQ concentration.

After obtaining the LOQ, we shall  prove this is precise and accurate.

Inject the LOQ concentration six times and check the  repeat-ability.( Precision)

Spike The LOQ concentration of impurity to the test sample and  verify the % recovery.(Accuracy)

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Limit of detection is 3.3 times less to the Limit of quantitation.

simply dilute 3.3 mL of LOQ solution to 10 mL with the diluent and analyse. the peak shall be visually detected and Signal to noise ration is about 3.

Usually LOD is not required for Quantification methods. It applies to the limit tests like TLC..

Description and solubility requirement as per USP/BP/EP

Description and solubility requirement as per USP/BP/EP :

These tests are only for information but not standards does not need to comply.

Long time ago, color and other organoleptic characteristics (taste, odor) and description (including the solubility and clearance of the solution) pertaining to an article, formerly included in the individual monograph, were considered subjective and general in nature. Now, this information is provided in the "Description and Solubility Section" of the USP-NF for those who use, prepare, and dispense drugs, solely to indicate descriptive and solubility properties of an article complying with monograph standards. The properties are not in themselves standards or tests for purity even though they may indirectly assist in the preliminary evaluation of the integrity of an article.

This explanation is so stated under the subtitle: “Description and Relative Solubility of USP and NF Articles” at the beginning of the section titled: “DESCRIPTION AND RELATIVE SOLUBILITY”.

Dirty equipment Clean Hold time studies :

Dirty equipment Hold time studies :

Now a days  the auditors are asking about the Dirty equipment Hold time study report in cleaning validation:

What is dirty equipment : 

Uncleaned equipment over a period of time

What is dirty equipment Hold time : 

The time between "after use" and "before cleaning" of equipment.


What to study : 
whether the cleaning process is capable enough to clean the dirty equipment and meets the acceptance criteria.

Plan :

Keep the equipment idle after usage(unload the material) and do not clean for 24 hours. collect the physical traces of sample after 8,12 and 24 hours respectively. then clean the equipment

Check for degradation using related substances method for the samples of 8,12 and 24 hours collected from different locations of the equipment.

Collect and check the rinse/swab sample after 24 hours for the product absence.

Clean hold time studies : 
The time period between "after cleaning and before use" of equipment.

Procedure :
After cleaning of an equipment, keep it idle for 48 hours and check swab sample for microbial counts.
TAMC : 1000 Colony forming units/swab
TYMC : 100 Colony forming units/swab

Temperature, Humidity and MKT in stability studies

Temperature, Humidity and MKT in stability studies:

*Relative humidity is a measure of how close the air is to reaching saturation with moisture

*Saturation is the point when the air can hold no more water vapor and is essentially full.

*Let us take  a glass filled with wine half full.

     The glass can hold 200 mL

*100 mL wine is in the glass - Absolute

*Content in % is 50 - Relative

Mean kinetic temperature :

*Across the year, temperatures vary from zero to 40°C

*The mean kinetic temperature will be the climatic condition.

*It is somewhat similar to average, But not exactly.

*It was calculated by using Arrhenius equation.

*For example, INDIA climate: 30°C / 75%RH.

*when Air becomes warm, Warm air can hold more moisture, because air expands

Relative humidity decreases.

*Air becomes cool, Relative humidity increases