Rouge is visible as layers of reddish coating on stainless steel surfaces inside pharmaceutical equipment and loops.
It can be removed using innovative pH-neutral products that do NOT damage the equipment and can therefore be used repeatedly and periodically without damaging the component.
Rouge: don’t underestimate it
It is not unusual for rouging to affect stainless steel surfaces.
Not even the main stainless steel conduit systems used in the pharmaceutical and biotech industries can escape the effect of rouge.
In most cases rouge is visible within WFI systems as layers of a reddish coating, whereas in steam circuits the rouge stratification that affects the surface is fairly dark and mainly concentrated inside the joints.
In these cases particles of rouge can also be present in other areas of the circuit and can therefore be removed by the flow of the product within the system.
It is advisable not to underestimate the problem of rouging, particularly in the “clean” pharmaceutical sector.
Rouging removal: be quick!
The passivation of new systems is an extremely important way to prevent rouging.
Despite this, however, it’s important to remember that protection doesn’t last forever!
A range of factors such as a low oxygen percentage combined with high temperatures can lead to the formation of rouging.
The only sure way to reinstate the surface is to carry out normal derouging using a neutral, non-aggressive product and to re-passivate the system.
First visible problems caused by rouge:
- oxidised particles of heavy metal that cause contamination
- micro-corrosive attacks on stainless steel surfaces
- a tendency for bacteria to proliferate on the biofilm of the stainless steel surface