 As we have seen in our previous modules that agitation system or agitator system consists upon a one part that is known as agitator consists upon motor, regulator, seal, shaft and impeller. But then other part that is not directly associated with this system but that is attached with the body vessel that is known as baffle. So in this slide you can see the graphical representation of the baffle as you can see here that the baffles these are the small outgrowth inside the vessel. So that basically help to create the turbulence in the fermentation medium while agitation is going on. So that create the hindrance in the flow in a smooth flow because when there will be a smooth flow then there is a layering in the medium. So in fermentation process layering is not required because when there will be a layering then there is not equal environment inside the fermenter vessel. So that the material that remain outside and that some material remain inside all the way. So baffles help to give the equal chance of all kind of the media material and the organism to have the equal distribution over the fermenter vessel. So what will be the maximum height of the baffle we have seen in our module when we are talking about the fermented design with multi impeller fermenters. So that with the 3 models gave the ratio between the depth with the diameter and the baffle height. Apart from the baffles and other systems in industrial scale fermenter when the body is made up of stainless steel then there is a there should be the provision to observe inside the fermenter. So in a very large fermenter there are small glass openings we can say that they are known as the screen or there are small window by which we can see we can observe the process inside in some fermenter that have the assemblies with the light. So when we switch on the light and then we can see inside the fermenter. So you can see in this slide one worker working on in a fermenter that is visualizing inside the fermenter. So this part of the fermenter is very critical because the glass that has to you that can have the property to withstand the sterilization conditions as well as that have a very transparent. So as I have talked about the seals and the o-rings that is properly fixed on this we can see that the screen or the window. So then other on a very large scale fermenter when the fermenter height is a very significant then we can say that we have to wash out we have to clean the fermenter and sometimes a worker or a technicians sometime that need to have a maintenance. So in a large fermenter then the workers has to go inside physically inside the fermenter just by opening a window of the fermenter and then go to the bottom of the in such cases then there is a need of the ladder. You can see here the ladder. So ladder sometimes are designed in such a way that have in a some fermenter that is only simple ladder as you have seen in a different buildings either a small we have a ring but sometimes in a some fermenters baffles can be designed in a such a way that can be utilized as a ladder. So just by mixing the ladder and the baffle we have we see two properties in a one shot. So these are different design requirement on a large scale fermenter as you have seen that ladder provision, window provision and then baffle provisions along with the agitation system. So for as we have seen in our 13 basic principle of fermenter design when we talk about their maintenance provisions in their labour provisions and other provisions. So very each and every step for designing the fermenter is very critical. So in our later module I will talk about in detail the agitation system because the whole agitation system because the main focus of the agitation system is the mixing. So how the mixing are a good mixing can be achieved there is only possible when we have a suitable design of the impellers. So we will talk about those impellers in detail in our later modules.