Germicidal devices and applications of same

A germicidal device, comprising:

• a lighting member operably in an on-state in which the lighting member emits ultraviolet (UV) light for killing microorganisms in an area, or in an off-state in which the lighting member emits no light, wherein the lighting member comprises a light source for emitting the UV light having a wavelength of 185 nm, wherein the light source comprises one or more UV light-emitting diodes (LEDs), and a low-pressure mercury lamp, and wherein the microorganisms include bacteria, fungi, viruses and/or spores;
• a sensing member configured to detect a movement in the area, an acoustic wave in the area, an intrusion into the area, an expiration of an on-state time period in which the lighting member is in the on-state, an expiration of an off-state time period in which the lighting member is in the off-state, and an instruction from a remote operation, wherein the sensing member comprises a built-in sensor unit comprising at least one motion sensor, at least one acoustic sensor and at least one timer, and a remote sensor unit consisting of a photo eye system and/or an electric fencing system, wherein the electric fencing system is configured to detect the intrusion into the area when a person or animal approaches to an invisible electric fence that is generated by the electric fencing system and surrounds the germicidal device, and wherein the photo eye system is configured to detect the intrusion into the area when the person or animal approaches to an invisible infrared fence that is generated by the photo eye system and surrounds the germicidal device;
• and
• a microcontroller unit (MCU) coupled with the lighting member and the sensing member, wherein the MCU is configured to control operations of the lighting member in a respective state in accordance with a detection of the sensing member in the area, such that when the lighting member is in the on-state and the sensing member detects an intrusion of the person or animal into the area, the MCU immediately switches the lighting member from the on-state to the off-state,
• wherein the lighting member, the built-in sensor unit and the MCU are assembled in a single unit.