An intelligent FFR with a self-adjustable ventilation fan

ABSTRACT

This article presents an intelligent Filtering Facepiece Respirator (FFR) with a self-adjustable ventilation fan for improved comfort. The ventilation fan with an intelligent control aims to reduce temperature, relative humidity, and CO₂ concentrations inside the facepiece. Compared with a previous version of the FFR, the advantage of this new FFR is the intelligent control of the fan's rotation speed based on the change in temperature and relative humidity in the FFR dead space. The design of the control system utilizes an 8-bit, ultra-low power STC15W404AS microcontroller (HongJin technology, Shenzhen, China), and adopts a high-precision AM2320 device (AoSong electronic, Guangzhou, China) as temperature and relative humidity sensor so that control of temperature and relative humidity is realized in real time within the FFR dead space. The ventilation fan is intelligently driven and runs on a rechargeable lithium battery with a power-save mode that provides a correspondingly longer operational time. Meanwhile, the design is simplistic. Two experiments were performed to determine the best location to place the fan.

KEYWORDS:

• FFR
• intelligent control
• ventilation fan

Funding

This work was supported by Hubei Provincial Natural Science Foundation of China (Grant No. 2015CFB307), the Fundamental Research Funds for the Central Universities of China (Grant No. 2042014kf0034), and the scholarship from China Scholarship Council (CSC) under the Grant CSC No. 201606275005. The authors gratefully acknowledge all the support.