“Parents should be aware that preparations are not sufficient to guarantee a safe expansion of school opening on Monday in Hertfordshire,” the National Education Union has warned.

From Monday, schools across England are welcoming back pupils in reception, Year 1 and Year 6, under government plans to ease the coronavirus lockdown.

However, parents are not under any obligation to send their children in and, with widespread concern that it is too soon to be safe, many have decided not to.

The government has confirmed that parents will not be fined for their children’s non-attendance, and schools will not be accountable for absences.

On Friday, Paul McLauglin, regional secretary of the eastern region of the NEU, said: “We have had some constructive conversations with many local authorities across the region. One of the issues that remains outstanding in most areas is the issue of adequate provision of PPE.

“In Hertfordshire the situation is particularly dire and we are concerned they are not taking the issues seriously enough.

“The local authority has admitted there are no gowns, and limited supplies of gloves, and yet they still are stating schools can expand opening safely. This is not true and puts children’s safety at risk.

“Parents should be aware that preparations are not sufficient to guarantee a safe expansion of school opening on Monday in Hertfordshire.

“Parents are being told that schools are safe when clearly in many cases they are not.

“We are urging caution. Wait until proper arrangements are in place. Why risk staff and students’ health unnecessarily? Adequate supplies of PPE is a basic requirement for all schools.”

The UK’s largest union, UNISON, has also waded in. Nalin Cooke, UNISON’s eastern regional organiser, said: “Hertfordshire schools need much more time to complete their risk assessments and put processes in place to guarantee the safety of everyone involved.

“Parents will also need reassurance that teaching assistants, caterers and other support staff have the protective kit they need to keep their children safe.

“Ministers claimed they had placed a ‘protective ring’ around care homes, but failed miserably. School students are obviously at a much lower risk, but we can’t allow classrooms to become the next breeding ground for this pandemic.

“Everyone wants schools to reopen. A delay allows unions, the government, local authorities and academies the space to work together and make sure schools reopen safely.”

Councillor David Williams, leader of Hertfordshire County Council, said: “I believe that both our planning and that of schools has been very thorough. Possible risks have been reviewed in every school by headteachers, with advice and support from the council. Where necessary, safeguards have been put in place. I am confident it is now safe for schools to reopen in the planned and measured way proposed by the government. I am confident our children will be safe in school, as will staff, and I would urge parents now to join in returning their children to school.”

A spokesman for the county council added: “It is clear pupils are suffering from the current closure. This is not only the effect of the closure on their learning, but also the impact on children’s social development and emotional wellbeing.

“The government in its decision-making has access to resources and advice which Hertfordshire County Council does not. It is able to look at the effects of school reopening as part of a wider strategy for managing the pandemic. Its decision-making is informed by schools as part of our wider social system, rather than in isolation. HCC is happy, therefore, to follow the national guidance and not seek to second-guess government judgements.

“For primary-aged pupils, in particular, the evidence is very strong that they are not at risk of serious illness to anything like the extent that older adults are. That should be a reassurance to parents.

“Each school will only reopen when the headteacher is satisfied it is safe to do so, after completion of a thorough risk assessment, so all possible measures can be taken to reduce risk. For many schools, they will not be able to bring back all children in the relevant age groups immediately, for legitimate reasons round safety and proper operation. The county council understands and supports schools in the challenges they face here.”

Cllr Terry Douris, HCC’s executive member for education, concluded: ”I think we can be confident that schools, alongside staff, will do the very best they can to operate and develop the system of partial reopening safely and in the interests of staff, parents and pupils, both in terms of safety and education.”