Northern Ireland's Health and Safety Executive (HSE) has received nearly 1,000 complaints about conditions in workplaces since March 16.
HSE chief executive Robin Kidd said there had been 991 complaints lodged since the introduction of lockdown.
Speaking to the Assembly's Economy Committee, Mr Kidd added that there had been 666 investigations, with 325 of them being passed on to other bodies, such as local authorities, for closer investigation.
However, he also praised the local food processing sector for its ability to adapt.
Mr Kidd accepted that companies were lagging behind in the introduction of measures designed to improve workplace safety, but said it was only because food processing, unlike manufacturing, had been in constant operation since the introduction of lockdown.
The HSE chief executive also stressed it was difficult to see how certain sectors could become compliant with social distancing guidelines.
However, he added: "Social distancing will be with us for some time, so it's not a short-term fix or 10 to 12 weeks - it's for long-term survival."
Mr Kidd stressed that it was not within his organisation's power to close down businesses that break the rules.
He also said he had sought details about social distancing measures at Northern Ireland's three airports.
He made the comment in reference to widely publicised pictures showing a busy Aer Lingus flight from George Best Belfast City Airport to London Heathrow on Monday morning.
Mr Kidd told the committee: "We have been in touch with all three airports asking them to confirm what social distancing measures are in place."
The HSE is responsible for enforcing and informing the guidelines around workplace safety.
That includes at Belfast City, Belfast International and City of Derry airports, but it does not extend to what happens on board aircraft themselves.
The HSE chief executive said that after contacting Belfast City Airport, "I am assured that they have improved social distancing measures and (introduced) additional staff to remind passengers as they travel through the airport".
"One of the challenges around an aircraft is the very small and confined space. It will add to the timing of loading passengers to adhere to social distancing. That is one of the real challenges going forward," Mr Kidd added.
The Civil Aviation Authority is responsible for what happens on board aircraft.