Supermarkets are racing to install measures to keep shoppers and staff at least 2 metres apart after the government called for an immediate increase in safety efforts to contain the coronavirus outbreak.

On Tuesday, Sainsbury’s, Asda, Marks & Spencer and Waitrose confirmed they would begin limiting the number of shoppers in stores at any one time . Most retailers said they would have marked areas outside each store where customers will be instructed to queue two metres apart.

Waitrose said restrictions would be specific to each store and it was introducing marshals to manage queues outside shops.

New rules announced on Monday night stipulate that retailers remaining open during the lockdown, such as supermarkets, must ensure there is 2-metre distance between customers and staff and that shoppers enter in small groups, so that spaces do not become crowded. The government has also ordered retailers to manage queues outside their stores.

The rules apply to supermarkets, but also to pharmacies, home improvement stores, newsagents, post offices and even bike shops, all of which have been classed as “essential” retailers under new rules which have led to the shutdown of thousands of high street stores.

Waitrose, the Co-op and Sainsbury’s are taking further measures to protect staff, including closing checkouts where two assistants sit back to back. Waitrose, Lidl and Asda are also joining Sainsbury’s, Morrisons and a number of other retailers in installing perspex screens to protect check out staff.

Morrisons and Aldi to put up checkout screens to protect staff Read more

Asda said from Wednesday it was going to be asking shoppers to only touch items that they wanted to purchase and offering hand sanitiser at the entrance and exit of stores.

Marks & Spencer said it was cleaning trolleys, baskets, screens and all touch points every hour and deep cleaning them every night so that customers could “shop with confidence”. It is also installing what it called “sneeze guards” at tills as an extra precaution.

Bérangère Michel, the executive director for customer service at Waitrose’s parent group, the John Lewis Partnership, said: “While these measures will dramatically change how people shop and interact with others in our stores for the moment – they are absolutely vital to ensure that our customers can shop safely and that our partners are protected as they go above and beyond to serve shoppers in this time of crisis.”

Christian Härtnagel, the chief executive of Lidl GB, said: “We hope this additional safeguard will help to provide extra reassurance for those both working and shopping in our stores.”

The Usdaw union, which represents store workers, has called on retailers to protect staff further with measures including:

Limiting the number of customers in store at any one time.

Increasing security.

Telling customers to shop alone if possible and only buy what they need.

Enforcing essential workers’ and vulnerable people’s shopping hours.

Usdaw has also raised concerns that staff from Argos standalone stores, which closed on Monday, have been asked to work in Sainsbury’s supermarkets.

The Usdaw national officer, Dave Gill, said: “With the overwhelming pressure on all food retailers, it is inevitable that companies are going to look at redeploying staff within the business. However, this is extremely unsettling for staff in what are already difficult and testing times for everyone.”

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Sainsbury’s is to keep open Argos concessions within its supermarkets despite the catalogue shops falling outside the “essential retail” category of stores ordered to close. Sainsbury’s said the concessions were staying open as they were part of its supermarkets. The retail group’s Habitat outlets have shut.

Pressure on staff has intensified as shoppers stockpiled goods and switched from dining out to cooking at home. The closure of all non-essential retailers is likely to add to demand in supermarkets, with little capacity to increase home deliveries in the short-term.

The average spend per supermarket trip rose 16% in the week ending 17 March. In the same period, there were an additional 15m food shopping trips – an increase of 12% – according to the market analysts Kantar, amid widespread concern about shortages of essentials.