A union has questioned the decision to keep a wind turbine factory open during the coronavirus outbreak.
Siemens Gamesa makes giant blades for offshore wind farms at the £310m plant in Hull and said it had changed working methods to enforce "social distancing".
Unite said it wanted clarity on whether the firm's work was "essential".
Siemens said the Department for Business, Energy & Industrial Strategy classified "renewable energy workers...as essential at this time".
The site closed down for a week to introduce new measures, which include thermal cameras on entrances to take the temperature of staff.
Other changes include opening up extra space so workers can spread out, staggering shifts and break times, issuing personal protective equipment, banning visitors and offering flexible working to staff whose partners are key workers.
"We have changed the pattern of work throughout the factory so that the two metres is built in to the way we work," a spokesperson said.
Unite said its members were "rightly anxious whether the new health and safety measures are adequate enough".
The union added: "We want to discuss with the company whether the production of blades is an 'essential' industry at this time. If it is not, we would want our members furloughed on full pay."
About 750 people are employed at the site, which opened in 2016 and supplies 250ft-long (75m) rotor blades for the world's largest wind farm off the Yorkshire coast.