By Michael McHugh, Rebecca Black and David Young, PA
Frontline doctors and nurses are frightened, Stormont's deputy first minister said.
Good progress is being made in acquiring more personal protective equipment for those tackling the coronavirus pandemic, Michelle O'Neill added.
An order of 5.5 million items of clothing began arriving in Belfast on Monday.
Mrs O'Neill said: "I have spoken with many frontline healthcare workers.
"You have told me you are frightened. You have told me you are worried about being able to do your job safely. You have told me that you are worried for your families.
"We see you, we hear you, and we are working night and day to make sure you get the protection that you deserve."
She said good progress is being made in securing more personal protective equipment and this remains a top priority for the devolved ministerial Executive.
Prospects for a joint order of kit from China placed with the Republic of Ireland have fallen through.
A formal memorandum of understanding has been devised by the health ministers north and south of the Irish border.
Mrs O'Neill added: "While we have two jurisdictions, we are one island and this means it's sensible that we have common action to combat this deadly virus.
"The Covid-19 pandemic does not respect borders, so there must be a common approach to action in both jurisdictions on this island."
First Minister Arlene Foster also appeared before an ad hoc committee of Assembly members at Stormont on Tuesday.
The DUP leader said: "We are doing everything we can... to get the right PPE to those who need it at the right time.
"We will continue to expand the testing of healthcare staff as quickly as possible.
"We fully understand the frustration that more staff have not yet been tested, both in the healthcare sector and across other sectors.
"We understand that people are concerned about potentially unknowingly passing on the virus to their loved ones, or those they are looking after.
"And we appreciate that people with Covid-like symptoms are frustrated at having to self-isolate while their colleagues are under pressure, when the results of a test may allow them to get back to work."
She said difficulties in scaling up testing are not due to a lack of effort or will.
"There are significant challenges including laboratory and staffing capacity and the unprecedented levels of global demand for testing reagents and swabs."
Meanwhile, Stormont health minister Robin Swann has been subjected to online threats which have been roundly condemned by Mrs Foster and Mrs O'Neill.
Former UUP leader Mike Nesbitt campaigned with Mr Swann for election to the Assembly in 2011.
He said his children's lives were in the hands of his colleague, who leads the NHS' response to coronavirus, and appealed for greater courtesy.
He said: "Loving each other may be a bit of a stretch but for God's sake we need to show each other a bit of respect."