Difference Between Positive and Negative Pressure Isolators
Understanding the different types and classifications of Barrier Isolators is important to ensure the right Barrier Isolator is selected for the right application.
This technical blog provides a basic understanding of Barrier Isolator Types and Classifications.
Foreword
All products can be misapplied across all industry sectors. Therefore understanding the most appropriate product type, classification and configuration for your application is therefore THE secret to equipment longevity, operational sustainability and operator health, safety and welfare.
For example, you wouldn't purchase a Formula one, Lamborghini or Ferrari sports car if you intended to drive off-road on mud and dirt tracks.
Equally, you wouldn't purchase a tractor if you wanted to race around a motor track at high speed.
The same selection for the application criteria applies to Barrier Isolators.
Types of Barrier Isolators
The Type of Barrier Isolator is essentially split into four main areas;
Classification based on the Type of operation
Negative Pressure Isolator
Positive Pressure Isolator
Classification Based on Material of construction
Rigid Isolator
Flexible Isolator
This simple classification is illustrated in the diagram to the right.
Negative Pressure Isolators :
Designed to maintain negative pressure inside
Used when the product is toxic, hazardous
Operator protection is more important
To prevent contamination of external environment from the product.
Explosive reactions
Controlled atmosphere such as a Nitrogen N2 atmosphere
Positive Pressure Isolators :
Designed to maintain positive pressure inside
Used when the product is sterile
Product protection is more important
To protect the product from the contamination from external environment.
Controlled atmosphere like sterile atmosphere
Rigid Isolators :
Rigid and sturdy, long life, Withstand corrosive environment, resistant for solvent atmosphere
Generally made of SS316L material body, Glass front panels.
On specific requirement it can also made from noble alloys like Hastelloy, Inconel, Titanium
Internal surface can be coated with PTFE or Stancoat with high chemical resistance
Flexible Isolators :
Made of plastic thin films, soft and flexible in nature
