what part of vacuum bag is the hepa filter?

In a vacuum cleaner, the HEPA (High-Efficiency Particulate Air) filter is typically a separate component from the vacuum bag itself.  Here's a breakdown of their roles and locations:

Vacuum Bag:

This is the primary container where dirt, dust, and debris are collected.

It is usually made of a paper or cloth material that allows air to pass through while trapping larger particles.

The vacuum bag is usually located inside the main body of the vacuum cleaner.

HEPA Filter:

This is a high-efficiency filter designed to trap very small particles that the vacuum bag or standard filters might miss, such as pollen, pet dander, dust mites, and even tobacco smoke.

HEPA filters can capture particles as small as 0.3 microns with 99.97% efficiency.

The HEPA filter is often located after the vacuum bag in the airflow pathway, meaning the air passes through the vacuum bag first and then through the HEPA filter before being expelled back into the room.

It is usually found in a designated compartment within the vacuum cleaner, sometimes at the exhaust end.

In summary, the HEPA filter is not part of the vacuum bag itself;  rather, it is a separate filter that further cleans the air after it has passed through the vacuum bag.