Boris Johnson has promised that the government will next week publish a “comprehensive plan” on reopening businesses, with professional bodies working through the weekend to help draw up detailed guidelines on working during lockdown.

Large parts of the economy remain closed because of concerns that companies may not be able to adequately protect their workers, but the government is keen for firms to return to work where possible in order to cushion the blow to the economy.

The government is due to announce its latest decision on whether to extend lockdown conditions on 7 May, although there is little expectation of any major relaxation of rules, with health services still under pressure.

However, the prime minister on Thursday said he expected to present “a comprehensive plan” on how to get the UK economy moving as well as providing childcare for workers, allowing travel to work and allowing safer work within businesses.

The UK government has expanded the criteria for who qualifies for a free test for coronavirus to all essential workers and their families in England – up to 10 million people. The list of essential workers is the same as the one used to allow the children of key workers to carry on going to school during the lockdown:

Health and social care
Frontline health and social care staff such as doctors, nurses, midwives, paramedics, as well as support and specialist staff in the health and social care sector. In addition it includes those working in supply chains including producers and distributors of medicines and personal protective equipment.

Education and childcare
Nursery, teaching staff and social workers.

Key public services
Those required to run the justice system, religious staff, as well as those responsible for managing the deceased, and journalists providing public service broadcasting.

Local and national government
Administrative occupations essential to the effective delivery of the Covid-19 response or delivering essential public services.

Food and other necessary goods
Those involved in the production, processing, distribution, sale and delivery of food.

Public safety and national security
Police, support staff, Ministry of Defence civilian staff and armed forces personnel, fire and rescue staff, and those responsible for border security, prisons and probation.

Transport
Those who will keep air, water, road and rail passenger and freight transport modes operating.

Utilities, communication and financial services
Staff required to keep oil, gas, electricity, water and sewerage operations running. Staff in the civil nuclear, chemical and telecommunications sectors. Those in postal services and those working to provide essential financial services.

The business secretary, Alok Sharma, has been gathering views from businesses and lobby groups on guidelines that should be implemented, giving details of how different sectors should adapt. The advice is expected to cover different types of workplace, such as factories, offices, shops, logistics and outdoor work such as farming and mining.

While there is no legal impediment to companies returning to work – aside from non-essential retail and public venues that have been explicitly shut down – some businesses are concerned they could face a backlash in the absence of a clear signal from the government.Here is how the different anti-coronavirus measures could work:

Factories

Any work that cannot be done with social distancing should be done with workers standing either back to back or side by side – rather than face to face. Cleaning of work surfaces will be more regular and shifts should be staggered to prevent large congregations of workers at factory gates or in rest areas – in which 2-metre distancing will be enforced.

The carmaker Vauxhall has made face masks and eye protection compulsory at all times. However, sources in other industries have said the government is unlikely to mandate this across the country, given the need to prioritise personal protective equipment for the NHS.

Offices

There is little prospect of a return to working en masse in offices in the coming weeks, with working from home still encouraged among those who can do so. However, for those who must return to offices, desks will be spaced out and start times could be staggered to prevent rush hour crowding on public transport.

Retail

Britons have already become familiar with distancing requirements in shops deemed essential by the government. The British Retail Consortium and the Usdaw union have drawn up guidance that covers issues ranging from limiting access to public toilets, to the installation of protective screens at tills and keeping changing rooms permanently closed in clothes shops in order to prevent contamination.

Delivery services

Warehouses and trucking companies have been in demand like never before as people are stuck at home. Within warehouses safe practices are almost identical to factories, while delivery drivers who interact with consumers as part of their job need to wait for the customer to pick up packages at a safe distance.

Outdoor work

In farms, quarries and mines, workers should work side by side if they are unable to carry out their jobs 2 metres apart, and enclosed spaces such as machinery cabs should have windows left open to allow for ventilation. The sale of goods – such as farm produce – should not encourage the gathering of crowds, with online orders and deliveries recommended.

Construction

Some housebuilders had faced protests over continuing work during lockdown, with concerns that some parts of the job are impossible to do while maintaining 2-metre distancing. However, the housing minister, Robert Jenrick, last week gave clear guidance to the construction industry that it should return to work if possible. The housebuilder Taylor Wimpey is manufacturing a bespoke face shield, which will attach to a construction hard hat and will be used on all its sites for two-person tasks. Large sites such as the Hinkley Point C nuclear power station will have split shifts to reduce overlap.

Transport and tourism

While transport is not thought to be among the sectors to be covered by new business department guidance, any large move back to work will require more public transport. Bus and train companies are hoping for continued government funding to allow them to operate with empty seats – a costly move – to preserve 2-metre distances.

Any recovery of the airline industry is likely to be more reliant on international agreements. However, the Hungarian budget airline Wizz Air on Thursday said masks would be compulsory on its flights from now on, with limited flights to resume from Luton airport on 1 May. The Ryanair boss, Michael O’Leary, has rejected the idea of leaving the middle seat empty on planes in order to maintain physical distancing.

Hospitality

There is little expectation that public gatherings will be allowed for months, given the focus on reducing the potential for coronavirus to spread. The JD Wetherspoon pub chain plans to reopen in June, although few analysts believe that is likely. Any pre-vaccine reopening would need strict social distancing and cleaning routines – if customers could be persuaded to return.