A portable device called 'Fog Pass' has been designed and introduced for trains by the Northeast Frontier (NFR) to help drivers' visibility during the foggy winter months, said an NFR spokesperson on Saturday.

The device is a low-cost, Global Positioning System (GPS) based equipment that will be used when visibility reduces and running trains at permissible speed becomes risky, said NFR chief spokesman Pranav Jyoti Sharma.

"The device is an audio-visual navigation assistant in essence and displays the name and distance of approaching signals and other critical landmarks on track like Level Crossing Gates. It also provides voice guidance on real-time basis." – Sharma said.

The device was not a permanent fixture but can be carried by drivers whenever required.

"It weighs less than 1.5 kg and operates on rechargeable Li-ion batteries.

The introduction of the device is in line with the recommendation of the High-Level Safety Review Committee (Kakodkar Committee) constituted by the Ministry of Railways in 2011.