The deaths of dozens of bus workers who were exposed to coronavirus has led Transport for London (TfL) to commission a study the city’s mayor has described as “deeply personal”.

The two-part study will see TfL work with University College London (UCL) to “better understand the pattern of coronavirus infections and deaths among London’s bus workers”.

London Mayor Sadiq Khan said the study would ensure every possible measure was taken to protect “our heroic staff”.

“As the son of a bus driver, this is deeply personal to me,” Mr Khan added.

TfL said the two-part study was commissioned after the “tragic deaths” of 33 staff including 29 bus drivers.

The first part, due to take place in coming weeks, will review measures including cleaning and social distancing put in place by TfL during the pandemic to restrict Covid-19’s spread.

The second part, which will be run over some four months, will consider whether frontline transport workers are at greater risk of infection and death than London’s general population.

The study comes 10 days after unions called for tougher safety rules in response to data published by the Office for National Statistics (ONS) suggesting bus drivers were among workers with higher rates of death from Covid-19 than other staff.

Male bus and coach drivers were found to have a rate of 26.4 deaths per 100,000 compared to sales and retail assistants at a rate of 19.8.

TUC general secretary Frances O’Grady claimed the ONS figures showed the Government was “failing on workplace safety – with horrific consequences for our lowest-paid and most precarious workers”.

UCL Institute of Health Equity director Professor Sir Michael Marmot said it was “absolutely critical” that more was understood about the high level of coronavirus infections and deaths in London’s bus drivers.

As the son of a bus driver, this is deeply personal to me

“They are among our key frontline workers who are keeping society functioning during this Covid-19 pandemic,” he added.

Concerns have been raised that some peak time Tube trains and buses in London remain packed.

Britain’s train companies ramped up services from around 50% of the normal timetable to 70% this week to reflect coronavirus travel restrictions being eased.

Mr Khan said it was “crucial” demand for public transport remained “as low as possible”.

“I urge all Londoners to do their bit to keep our transport workers safe by only using public transport if you have no other alternative,” he said.