Members of the civil service's biggest union will strike for two days at the Disclosure and Barring Service next month in a dispute over the introduction of a new "customer contact" model.
PCS members who work in the complaints and complex enquiries team at the background-checking agency's Liverpool office will walk out on 9 and 10 December.
Officials working in the wider DBS customer services team will stage action short of strike from 9-24 December.
The dispute centres on the planned introduction of a new customer-contact model that PCS argues will impose an increased workload on "already stretched" staff, and which will see incoming calls routed directly to members of the complaints and complex enquiries team.
Among DBS staff's broader concerns are that employees of Hinduja Global Solutions – the outsourced contractor that operates the DBS contact centre – will be able to channel callers directly to the in-house team.
The new model, which involves the Max Contact telephony system, is due to go live in the second week of December. PCS said the planned industrial action will go ahead unless DBS either withdraws or amends its plans.
Fran Heathcote, general secretary of PCS, said members' views on the new contact model are being ignored by management and warned that the industrial action is likely to affect people who need DBS checks for their work.
"The new system has met with technical problems but the proposed system, as it stands, is causing our members a lot of anxiety and stress," she said.
"There are also issues with an outsourced contractor passing complaints about their work through to our members directly employed by DBS, which adds extra stress to their working lives.
"The employer still has time to resolve the dispute by listening to our members and addressing the problems with the new system before introducing it."
A ballot of around 50 staff in the customer-services team saw 86% vote in favour of strike action and 93% give their backing to industrial action short of strike in the dispute. Turnout was 54%.
A DBS spokesperson said: "DBS has been notified that a small number of staff working in our customer services team, who are members of PCS union, will be taking strike action and action short of strike.
"We do not anticipate that any industrial action will cause any delays to the processing of DBS checks, or for customers wanting to contact DBS for support. Measures are in place to ensure that DBS continues to provide a quality service to all customers.
"Quality and continuous improvement remain at the core of what DBS does, in our products, in the services we provide, and in the decisions that we make – including the development of our enhanced customer-service model."