Convex mirrors at the edge of the platforms and upgraded emergency talkback units are among a slew of recommendations made by the commissioner of railway safety on Day I of his probe into Saturday’s fatal accident at Park Street Metro station.

The CRS (Metro circle), J.K. Garg, who flew in from Delhi on Monday morning, sought enlarged footage from the CCTV cameras at Park Street station to ascertain which part of Sajal Kumar Kanjilal’s hand — palm or wrist — was stuck between closing door flaps of an air-conditioned rake, officials said.

The driver and the guard of the rake were suspended on Monday because their statements were “not satisfactory,” an official said.

Garg told senior officials who accompanied him to the station that a convex mirror at the edge of the platform would help drivers see what was happening outside the coaches behind him.

An alleged miscommunication between the driver and the guard is believed to be among the reasons responsible for Kanjilal’s death.

After entering the station around 12.40pm, the commissioner headed straight to the end of the platform that leads to the tunnel for New Garia-bound trains, where Kanjilal was found dead.

According to a preliminary post-mortem report, he was electrocuted.

The 66-year-old made a last-moment attempt to board the train at Park Street station and had a part of his hand stuck between the shutters of the first door of the third coach from the front.

With his hand stuck and the rest of him on a “5cm-wide footplate” at the base of the door, the train ran around 60m into the tunnel.

Garg saw the CCTV footage of the sequence of events leading to Saturday’s accident and asked Metro officials whether the images could be blown up for more clarity. A footage shows Kanjilal standing on what Metro officials said a 5cm-wide footplate at the base of the door of the coach. But it is not clear which part of Kanjilal’s hand — palm or wrist — is stuck between the door flaps.

There is no clarity yet on how the train started moving with Kanjilal’s hand stuck between the door flaps.

Metro officials have been saying that while a thin palm need not prevent the flaps from closing, a fist will be counted as an obstruction by the censors and leave a gap between the flaps.

“The commissioner thinks enlarged footage will help in ascertaining whether his wrist or palm was stuck. We have already shown him enlarged images but he wants them blown up further,” an official said.

From Park Street, Garg took a train to Tollygunge station, where the rake that was involved in the accident has been kept on the tracks adjacent to a platform (one that is used in an emergency).

Accompanied by Metro officials, Garg entered the rake through the driver’s cabin. Metro sources said the commissioner told the officials to attach voice recorders to the emergency talkback units so the conversation between a passenger and the driver could be analysed.

Those who were in the third coach when Kanjilal was trying to board it had alleged that the device had not functioned properly.

The CRS (eastern circle) had made similar recommendations after probing the December 27 fire on an AC Metro rake in the tunnel.

Garg is also said to have suggested that the third rail current collectors be insulated. Metro officials said Kanjilal had fallen off the train in the tunnel and got electrocuted after coming in contact with the third rail current collector.

The commissioner met the Metro general manager, P.C. Sharma, earlier in the day and headed for the Noapara car shed from Tollygunge.

“The probe will cover all aspects. I visited the accident site and checked the safety features on the train today. Next, I will speak with the persons involved — Metro staff and passengers,” Garg told reporters at Tollygunge.