Table 2.

Smart mask research prototypes from academic journals.

Name and purpose		Function	Feature
External pathogen detection and elimination
	ADAPT [22]	Pathogen sensing and mist spray activation	Sa: Airborne particle sensing Ab: Mitigation module on/off Cc: Bluetooth
COVID-19 detection
	SARS-CoV-2-sensing face mask [23]	Detects COVID-19 infection	S: Paper-based nucleic acid diagnostics
	Lightweight and zero-power smart face mask [24]	Monitor cough and check mask-wearing	S: Mask deformation C: RFd transponder
	AG47-SmartMask [25]	Monitor cardio-respiratory variables and to detect cough	S: Breathe pattern, skin/DSVe temperature, humidity, air pressure, HRf, and SpO2g C: Bluetooth
Respiratory disease–monitoring
	Smart face mask with Heat flux sensor [26]	Noninvasive body temperature and breathing rate–monitoring	S: Facial skin temperature and breathing rate C: LoRah and Wi-Fi
	Smart facemask for wireless CO2 monitoring [27]	Monitor CO2 in DSV	S: CO2 concentration C: NFCi
	Smart face mask with ultrathin pressure sensor [28]	Breath monitoring	S: DSV pressure change C: Wi-Fi connection
	Smart face mask with wearable pressure sensor [29]	Breath monitoring	S: DSV pressure change C: Bluetooth connection
	Smart medical mask for health care personnel [30]	Detect respiratory breathing, fever, and alert possible face irritation	S: DSV temperature, mask strain C: Wi-Fi
	Lab-on-Mask [31]	Monitor cardio-respiratory variables	S: HR, BPj, SpO2, and skin temperature C: Bluetooth connection
General health monitoring
	FaceMask [32]	Monitor cardio-respiratory variables and mask-wearing	S: Humidity, DSV or external temperature, volatile organic compounds. And head motion C: Bluetooth connection
	Facebit [33]	Monitor HR, respiration rate, mask fit, and wear time	S: HR, respiration rate, mask fit, and wear time C: Bluetooth
	Masquare [34]	Monitor cardio-respiratory variables	S: Respiratory pressure, HR, SpO2, and head motion C: Bluetooth

^aS: sensing.

^bA: actuation.

^cC: connectivity.

^dRF: radiofrequency.

^eDSV: dead space volume.

^fHR: heart rate.

^gSpO₂: blood oxygen saturation.

^hLoRa: long range.

ⁱNFC: near-field connection.

^jBP: blood pressure.