A scientist found dead at an HIV laboratory had stayed late to work with liquid nitrogen, an inquest has heard.
Damian Bowen was discovered at a laboratory connected to the Chelsea and Westminster Hospital by his colleagues on the morning of October 27 2011. He was 32.
The court heard Bowen had been working alone to freeze samples of blood. He was discovered wearing a lab coat and protective visor, on the floor of a room which contained a freezer of liquid nitrogen.
The inquest was told that the substance, if spilled, could make air unbreathable very quickly.
Dr Anthony Giles, who was called to the scene after Bowen's body had been discovered by a colleague, said "if [liquid nitrogen] is spilled in a room with not enough air it can be very dangerous. It leaves it without any oxygen. The effects of it can be very quick and you may not be aware."
The coroner said they are "likely to explore... Mr Bowen's training that he received at work [and] the circumstances of how he came to be found deceased at work in a room."
Loud alarms and flashing lights should sound in the room when it becomes filled with cold nitrogen, however these had not gone off when Bowen was found.
The Health and Safety Executive is still investigating whether there were any violations of workplace rules.
The inquest continues.