PAPRa Overview

Overview of the Tetra PAPRa.

Introduction to PAPRa

Many people are at risk for exposure to the COVID-19 virus and cannot afford to get infected. These people can isolate themselves, but often, their professions or requirements for daily life will take them in contact with other people, and they need some form of protection. Masks definitely help, but can become uncomfortable to wear, especially over long periods of time. This guide will walk you through creating a Powered Air-Purifying Respirator, which will protect the wearer and those around them from airborne viruses and bacteria, while at the same time providing positive airflow to the wearer’s face. That airflow makes sure that the wearer has a supply of fresh, clean air that has gone through a filtration process, and, in our tests, is the equivalent of wearing an N95 mask.

Or maybe you just want to walk around outside in an area with high particulate pollution, like Southern California during wildfire season?

The core of the idea is fairly simple: put a fan behind a filter in an airtight box, have the fan pull air through the filter, and push that air through a hose. The hose goes to a mask on the wearer’s face. When the wearer breathes out, air travels out through the filter in the front of the mask.

A completed build looks like:

MMR00133 edited XL

We have worn these PAPRas for multiple hours at a time and found them to be quite comfortable. Please send us any images you have of wearing your Tetra PAPRa that you’ve built, and if you want, we’ll post them on our website!

WARNING: We provide no warranty, implicit or explicit, that this device will work up to an N95 specification when built outside of a facility rated to do so. The only way to truly test one of these devices using something like a Portacount under controlled conditions.

PAPRa Build Guide (April 2024 Edition)

How to build the April 2024 version of the Tetra PAPR.

PAPRa Testing

Descriptions of the various tests and their results

Past Build Guides

Past PAPRa Testing Guides

These are tests that were run in the past but have since been superceded by more current tests.