Clean Room Condition Monitoring (Air Changes)

Objective:-

                        To ensure the air changes in sterile areas (clean Room) as per specification.

 Scope:-

                        It is applicable to the following areas:

§  Liquid Vial Injectabl filling area

§  Liquid Ampoule Injectable area

 Responsibility:-

QA Manager / Incharge

QA Officer

HVAC Engineer

 Procedure:-

In clean rooms, where Injectables are manufactured, it is necessary to periodically monitor the condition of the room. This is done by periodically measuring the velocity of the HEPA filtered air sent into the room and calculating the air changes in the room. This is an important parameter to assess the purging capacity of the air handling system. With the help of Anemometer the velocity of the air is measured at different sites of HEPA Filter out let and from this data the numbers of air changes are calculated.

 Calculation for number of Air changes in Sterile Area

a)      Number of Air inlets in the room = “N”

b)      Area of the inlet surface = Length X Width = “B” square feet

c)      Average Velocity of Air through an inlet = “C” Feet/min

d)     Volume of air = Area of surface X Average Velocity through an air inlet

i.e. = “BX C” Cubic feet / min

            Let “BX C” be denoted by “D”

e)      Volume of the room under consideration = L x W x H = E Cubic feet.

Now number of cubic feet of air through all filters / min = sum of cubic feet / min, of air through each filter in the room.

Thus CFM = D1 + D2 + D3 ………….. DN-1 + DN

Total CFM Di  denoted by “F”

                                                i = 1

f)       Total Cu. Ft of air through all filters in 1 hour = F X 60 CFH (where CFH = Cubic ft / hour)

Now 1 air changes = Total Volume of Room = E. eu.Ft.

Thus E Cu. Ft / Hour corresponds to 1 air change.

F * 60 Cu. Ft / hour corresponds to Air Change =   F * 60  Cu. Ft / Hour    =          Z air change

                                                                                      E Cu. Ft / Hour

 Criteria:-

Air changes / min (Z) should not be less than 20 for Class 10,000 and 5 or more for components preparation room.

Check Frequency:-

 Calculate the air changes for Class 100 area and component preparation room at quarterly frequency.