One of the largest producing gas fields in Russia's Yamal-Nenets region has escaped tougher quarantine measures after 20 airlifted workers tested negative for Covid-19.

According to the public health department of the regional administration, the workers were released on Monday from a hospital in the city of Nadym to where they were evacuated from the Bovanenkovo field on 27 March after suspected contact with a Covid-19-infected individual.

Three of the workers were reported to have exhibited flu-like symptoms at the time of evacuation.

However, double tests for the Covid-19 infection carried out in Nadym returned negative results.

On 16 March, all 20 employees flew in the same airplane from Moscow to a connection point in the city of Yekaterinburg with a person who was later confirmed as infected by the coronavirus.

Despite the good news, Bovanenkovo operator Gazprom dobycha Nadym is understood to have kept in place current restrictions on inbound travel of personnel to the Bovanenkovo, which came into effect on 28 March. An airport near the field, shut last week, has been re-opened only for cargo shipments, earlier on Monday.

Employees scheduled to replace workers on other major Gazprom gas fields in the Nadym-Pur-Taz district will be able to do so until 2 April, with inbound travel to come to the halt after that deadline, according to the operator.

Gazprom dobycha Nadym executive director Igor Melnikov said workers at Bovanenkovo and on its other Yamal Peninsula assets accepted an offer from the company to extend their shifts to two-and-a-half months instead of the previous one month.

Melnikov added that the company will pay 50% of the regular salary to those employees due to travel to the field soon, but who now have to remain at home following the decision.

Gazprom dobycha Nadym said that gas production at the Bovanenkovo field, which accounts for about 25% of Gazprom’s total output, “continues as normal”.

According to the Yamal-Nenets Public Health Department, no Covid-19 cases have been reported in the region as of 30 March.

The Yamal-Nenets region hosts a number of major gas fields operated by state-controlled monopoly Gazprom and the country’s largest independent gas producer Novatek, as well as oilfields operated by producers Rosneft, Gazprom Neft and Lukoil.

Almost all companies in the region said that they asked workers at the fields to extend their one-month shifts to between two and three months to reduce the risk of the pandemic, spreading to personnel.

Space is usually limited at dormitories built at the fields, with almost all workers having to share a room.