Back office healthcare staff are entitled to the coronavirus vaccine as part of the first phase of the rollout, the Department of Health has confirmed.
Staff within business services including procurement, IT and accounts have been able to register for the vaccine since Monday.
Priority groups who will be vaccinated first include those in care homes, the over 80s and healthcare staff.
More than 140,000 people in NI have received the first dose of the vaccine.
BBC News NI's Good Morning Ulster programme asked the department for clarity on who was able to get the vaccine after questions were asked about people in non-patient facing roles.
Some listeners said they understood only "front-line" medical staff were eligible for the vaccine.
The government's Joint Committee on Vaccination and Immunisation (JCVI) issued guidance on who should be able to get the vaccine.
'Vital role' in the health service
The JCVI advises the first priorities for any Covid-19 vaccination programme "should be the prevention of Covid-19 mortality and the protection of health and social care staff and systems".
The Department of Health told BBC News NI it was the protection of "healthcare systems" that meant that back office staff were on the priority list for the vaccine.
Business Services Organisation (BSO) is a department within Northern Ireland's healthcare sector that provides business support functions including IT, accounting and payroll.
A spokesperson for the department said staff played a vital role in keeping the health service going.
They added that staff had been involved in recruiting and training contact tracers, organising the distribution of PPE, paying staff, providing legal guidance and supporting the IT system.
"Protecting business services staff via vaccination to continue to deliver this support is essential for the smooth and continued functioning of the HSC [Health and Social Care] during the pandemic and particularly at this time of extreme pressure on our health service," a spokesperson said.
"If the back office is down, the front line can't operate effectively."
The latest statistics show 160,396 doses of a coronavirus vaccine have now been administered in Northern Ireland, with 21,690 of those second doses.