Periodic HEPA Filter Replacement of a LAF\RLAF

GOOD VALIDATION PRACTICE (cGVP) EQUIPMENT VALIDATION
1

Dear all,

please tell me what should be the frequency for periodic replacement of HEPA filters installed in LAF\ RLAF’s. Although pressure drop across HEPA is well within specified range.

Also tell what are the various tests to performed for ISO class-5.

ISO-14644 does define the periodic replacement of HEPA filters. is there any such guideline for the same.

waiting for reply.

Thanks

2

[quote=parveen.garg]Dear all,

please tell me what should be the frequency for periodic replacement of HEPA filters installed in LAF\ RLAF’s. Although pressure drop across HEPA is well within specified range.

Also tell what are the various tests to performed for ISO class-5.

ISO-14644 does define the periodic replacement of HEPA filters. is there any such guideline for the same.

waiting for reply.

Thanks[/quote]

Hi praveen, i am also a new to this area from my knowledge , i share to u, if wrong please…

While installation qualification of LAF to be done atleast for the following parameters:

  1. Type of LAF
  2. Blower CFM
  3. Total number of filters
  4. Air velocity supplied to the dispensing booth
  5. Air changes/ hour
  6. Noise level
  7. Power Requirement

Filter integrity test;-

  1. Test Equipment :- Aerosol photometer
  2. Make :-
  3. Model :-
  4. Chemical used for particle generation :- DOP/ PAO with Compressed N2 gas
  5. No of HEPA filters :-
  6. Suface area of HEPA :- (LxBxW)
  7. Total surface area of suppling Grills :-
  8. Surface area of prefilters :-

Accepance criteria:- 99.99%( % of transmission must be not more than 0.03%)

Equipments used for Qualification:-

  1. Aerosol photometer
  2. Anemeometer
  3. Magnehelic Guages
  4. Particle generator
  5. Particle counter.
  6. Anemometer.

Air velocity :-
Acceptance Criteria:- 90±10 fpm

After qualification, periodic requalification to be performed to ensure the working condition of the HEPA, if any of the above parameters fails, may need the change of HEPA.

Also ensure the working condition of the pressure indicating devices, its qualification and calibration status.

Soon i will send the guidelines about this…

Regards,
Ramajayam.

3

dear Sir,

Thanks a lot, it will quite helpful for me.

please try to provide related guidelines.

Thanks

4

Dear parveen,
HEPA filter replacement its truely based on daily monitoring and its performance test result.
All regulatry guidelines are not more spefic on replacement.
So in practice people will fix depends up on manufacturer recomendations or by past experience.
As per my opinion with proper prefilter cleaning, PPM and monitoring activity you can go for even 5 Years also.
At present we are replacing all HEPA filters every 30 months or has & when required with proper jestification in replacement Log Book.

5

Dear Sir,

Thanks a lot , please let know you are replacing HEPA after 30 months in an OSD facilty.

Thanks
Parveen

6

Dear Jayamrame,

Please provide any reference guidelines for the same.

Thanks in advance

7

[quote=parveen.garg]Dear all,

please tell me what should be the frequency for periodic replacement of HEPA filters installed in LAF\ RLAF’s. Although pressure drop across HEPA is well within specified range.

Also tell what are the various tests to performed for ISO class-5.

ISO-14644 does define the periodic replacement of HEPA filters. is there any such guideline for the same.

waiting for reply.

Thanks[/quote]

To the best of my knowledge.

There is no schedule frequency for replacement .However Periodical HEPA leak (DOP) testing ,Air velocity is to be done,

Another way is environment monitoring which is routinly or almost daily done in ISO 5 area.

8

Dear Parveen (again)

Frequency is something you decide yourself.
When reading all your questions throughout the forum I think your company eresuires some policy setting so you don’t scury off asking anything and everything when a question is raised.

The tests to perform you have already.

Decisions are made based on how your HVAC functions (example every HEPA has its own dP measurement or one dP per room???)
and what kind of processes you are performing in the respective cleanroom.

For deciding on a change frequency, make a risk assessment based on the processes that happen in the respective clean room.
And try to make some general rules. And have like a regular scan of the filter (integrity)

For example: If you have always HEPA’s on stock and you are fully equipped to change and immediately test the filter then, AND processes are not criticial AND every HEPA has its dP ==> you can consider on waiting till the dP alarm is triggered and replace and test the filter.
(one of the most bad attitudes)

Better practice would be , and again depending on HVAC setup and processes) , as soon as one of the filters in a clean room is failing then you change them all.

I know of companies that change all filters in grade A/B (in certain areas) every year cause the product they make is too valuable.

So make the assessments and try to device a policy.

regards

Johan