Staff at exam board AQA are to stage a 72-hour walkout that could affect the delivery of thousands of GCSE and A-level results, Unison announced on Friday.
Union members will walk out for three days, from Friday July 29 to Sunday July 3 and Unison warned industrial action is likely to escalate unless talks are reopened.
Many of the staff involved say they are struggling to make ends meet following successive below-inflation pay awards, Unison said.
The union said staff were given an increase of 0.6% last year, with 3% offered this year though AQA insist staff were actually offered 5.6%.
Unison official Lizanne Devonport said the workers have been left with “no other option” but to strike.
“Pay has been falling behind prices for years and 3% isn’t a wage rise, with costs spiralling it’s a pay cut,” she said.
“Things are so bad staff are fear ful they will no longer be able to make ends meet.
“Workers only strike as a last resort. They’d rather be doing the jobs that they’re proud of. They don’t want to disrupt students and know how important exam results are to them.”
An AQA spokesperson said: “Our priority is always to make sure students get the results they deserve on time - and we have robust plans in place to make sure any strike action won’t affect that. It’s a shame that Unison is claiming otherwise, as this is wrong and only serves needlessly to alarm students and teachers.
“We’re giving our people a pay rise that’s affordable and higher than many organisations, so it’s disappointing that Unison has decided to take strike action. The vast majority of our staff don’t support a strike, as only around 5% of our workforce and well under half of Unison’s own members voted for it.
“Indeed, nearly nine out of ten of our staff have already opted in to our new pay framework and agreed to the pay rise, including many Unison members, so it’s hard to see what this strike is trying to achieve."
This is the latest in a long line of industrial unrest this year which has seen workers on the railways and the law courts strike while professions from teaching to midwifery are also onsidering industrial action.