Different Types of Diffusers Used in Pharmaceutical Clean Rooms (Controlled Area)

Different Types of Diffusers Used in Pharmaceutical Clean Rooms (Controlled Area)

Know about different types of air diffusers used in HVAC systems in pharmaceuticals to disperse the clean air in cleanrooms.

Air diffusers are used in clean rooms and other controlled areas to distribute the clean air passed through the HEPA filters. Diffusers are the important part of the HVAC system and play a vital role in the maintenance of the classified area.

The number of diffusers in a room depends upon the volume of the area, size of diffusers and required air changes per hour. Diffusers are mounted in the ceiling of the room to distribute the uniform air in the area and return risers should not be near the diffusers. Otherwise, air pockets will form that can increase the contamination level in the area. Place and type of diffusers to be used should be included in the HVAC system qualification.

Generally, three types of air diffusers are used in pharmaceutical industries.

1. Induction Diffusers
2. Perforated Plate Diffusers
3. swirl Diffusers

Induction Diffusers: Induction diffusers are generally used in offices and therefore also called office type diffusers. These diffusers direct the air to flow in different directions.WHO does not recommend these types of diffusers to use in pharmaceutical processing areas because these diffusers mix the fresh air with the contaminated room air (see figure) and the air should be replaced with the fresh air to minimize the contamination. In the areas where dust is liberated it is important to replace the air containing dust with the fresh air.

Perforated Plate Diffusers: These are the WHO recommended and widely used diffusers in pharmaceutical industries. They allow the air to flow in all directions replacing the air containing dust and contamination with the fresh air from the supply.

Swirl Diffusers: These rotating diffusers are also recommended by the WHO which rotates during the fresh air supply allow distributing the fresh air throughout the area.