The head of the Grenfell Tower inquiry was heckled as he met with residents for the first time.
Retired judge Sir Martin Moore-Bick told locals he would look into the matter to the "very best of my ability".
A video of the meeting showed him being heckled as he said: "I can't do more than assure you that I know what it is to be impartial.
"I've been a judge for 20 years, and I give you my word that I will look into this matter to the very best of my ability and find the facts as I see them from the evidence.
"That's my job, that's my training, and that's what I intend to do. Now if I can't satisfy you because you have some preconception about me as a person that's up to you."
However residents said his words of reassurance were "not good enough", with one suggesting arrests had to be made over the catastrophe in order to win their confidence.
Sir Martin has already faced calls to resign amid criticism and frustration from survivors that the apparent remit of his inquiry may be too narrow.
The meeting, held in a centre overlooked by the burnt-out west London high-rise block, took place as the Government said further tests will be carried out on samples from other buildings across the country.
Some 190 samples from buildings located across 51 local authority areas failed combustibility in tests rolled out after the disaster.
Experts will now look at how different varieties of cladding insulation with different types of Aluminium Composite Material (ACM) panels react in a fire, the Department for Communities and Local Government said.
At least 80 people were killed when fire tore through the 24-floor tower in the early hours of June 14, with the building's cladding suspected to be central to its spread.
Sir Martin promised to consider a broad range of evidence after survivors and residents threatened a boycott over the inquiry's scope.
An official start date for the inquiry has yet to be set, although he told the meeting that he was keen to have the terms of reference sorted before Parliament goes into recess, according to a resident who attended.
The inquiry's terms of reference, concerns about the health of people living near the blaze, air quality, evacuation procedures and the condition of the block were among the wide-ranging questions posed by attendees.