By September, the legal wrangling was still going on, the emails show, even though the suits had, by then, been released to the NHS.
"We are being drawn into the legalities", one official wrote, saying they'd been asked to provide a statement that PestFix's products had had the right safety documents.
"I have been contacted by [name redacted] today requesting a statement to the effect that HSE were provided with the required documentation by Pestfix… This is not factually correct," the safety regulator wrote.
The following day, another email reveals: "…various colleagues in DHSC are contacting those involved in the assessment of the Pestfix products requesting statements to the effect that HSE assessed the products and they were compliant - not factually correct".
An email, dated 25 June, said Pestfix was worried news its equipment had not completed necessary testing might leak to the public.
"We are very concerned about whom we speak to with regard to getting these suits tested as we do not want it to be made public knowledge that PPE from Pestfix has not passed HSE inspection," it read.
The firm added that, with the legal challenge looming, it hoped that new tests could be done quickly. This was so that "we and the DHSC can confirm that the product… has been certified and accepted".
The isolation suits were ultimately tested to the required standard, and on 6 August the regulator allowed them to be used for staff treating Covid-19 in hospitals.
But it insisted the products were relabelled because the description was incorrect. The decision says: "The product refers to itself as an isolation gown, but it is clearly a disposable coverall".