The NHS has reportedly been forced to cancel blood tests due to a green policy limiting air-conditioning units. This summer’s record temperatures are said to have put equipment in some GP surgeries out of action. The NHS has denied the claim.

Some GP practices have been struggling to keep room temperatures below the 25C needed to store blood samples, which can be affected by heat. The NHS Net Zero Building Standard details the service’s ambitions to decarbonise its estate, including by phasing out fossil fuel use.

It also says “mechanical cooling should be minimised as far as possible” in order to meet “thermal comfort criteria” and to reduce energy demand. Guidance for GP practices says they should explore other ways of cooling, including windows and better insulation.

This summer’s heatwaves have seen appointments cancelled because of risks associated with blood test tubes, which have to be thrown away if they are in hot conditions too long, according to the Telegraph.

The same publication reports that some patients have been invited to do another blood test as their samples were degraded.

Blood samples should be stored at temperatures between 15C and 25C, although they can be stored overnight in a fridge.

An NHS spokesperson said the claim is inaccurate and NHS guidance does not restrict the use of air conditioning where it’s needed to deliver safe care.

They added: “Where practices do not have the ability to maintain temperatures within the limits required for pathology equipment, NHS staff are doing all they can to limit the impact for patients and ensure any non-urgent blood tests that require rescheduling are done as soon as possible.”

Many GP practices are owned by GPs, who decide if fitting air conditioning is appropriate for their building. Dr Munro Stewart, the vice-president of the Royal College of GPs, said reliable diagnostics rely on clinical samples being stored in the right conditions and tested in a timely manner.

He added: “GPs and our teams will do our best to ensure samples are kept cool through use of fridges and air-conditioned rooms, but this will be more challenging for some surgeries.”

Shadow Energy Secretary, Claire Coutinho, said air con is the norm in many countries because it makes workers more productive and people more comfortable.

She added: “To effectively ban it in new homes and hospitals because bureaucrats think it uses too much energy is absurd. The Conservatives would end the de-facto air con ban and make Britain cool again.”

The Government in June denied there is an air-conditioning ban in the UK. It pointed to a £2,500 grant being made available to eligible homeowners in England and Wales to help more households access “low-cost” cooling and heating systems.