Thousands of union members are expected to parade through the streets of Brighton and Hove tomorrow in what is expected to be the biggest public sector action in decades.

Picket lines will also be manned across the county as public sector, teacher and firefighter unions take part in one day of strike action.

Union leaders promised services will be disrupted but said residents relying on council services in “life and limb” situations will not be put at risk.

Councils are hopeful that, for the majority of services, it will be business as usual on a day when a number of unions will air their grievances.

Members of the National Union of Teachers are striking in an ongoing dispute with the Government about pay, pensions and working conditions while Unison, Unite and the GMB union will strike over opposition to the Government’s 1% pay award that has been offered to staff. The Fire Brigades Union will also join the industrial action as part of its continuing dispute with the Government about pensions which will continue into next week with a planned eight-day strike starting on Monday.

Scores of schools are expected to close on the day, with 49 full closures and 27 partial closures in East Sussex and 20 closures and 21 partial closures in West Sussex announced so far.

The majority of Brighton and Hove’s 49 infant and primary schools and ten secondary schools are also predicted to close.

Court buildings and Jobcentres could also face disruption with Public and Commercial Services Union members taking action, although Government officials are confident the sites will remain open.

GMB branch secretary Mark Turner said “enough is enough” and public sector workers who have lost £2,000 in pay in real terms on average over the past five years should not pay for a financial crash they played no part in.

He added: “Services will be affected. There is no doubt about that.

“There will be some departments that will have skeletal service and some that will have no service at all. Certainly there will be no refuse collection or street cleaning during the strike.

“We are constantly in dialogue with the council about what services we will supply during the 24-hour strike.

“There will be some workers who will be given dispensation in terms of life and limb situations. You are not going to have a situation where a care worker will not be helping a disabled person or an elderly person if their circumstances are critical.

“Our dispute is not with the public and not directly with Brighton and Hove City Council, it is with the representatives sent to negotiate at a national level.”

Phil Clarke, secretary of the Brighton and Hove Trades Union Council, said: “The disruption caused by this strike is entirely the fault of the Government.

“We must not allow them to divide public and private sector workers – we all need a pay rise.

“If we value our public services we must stop the fall in pay, recognise fighting fires at 60 and teaching 60 hour weeks until 68 is not acceptable, and back these strikes.”

An East Sussex County Council spokesman said the authority was “not aware” of any other service disruptions outside of schools.

He added: “We will do our best to ensure that essential local services are maintained throughout the day to minimise any potential impact on those in the community who depend on our services.”

A West Sussex County Council spokeswoman said it had no control over the situation locally as the industrial action was the result of national disputes between the Government and the various unions.

The authority is advising parents to check with their child’s school to see what impact the action is likely to have on staff levels.

The council’s call centre will remain open during the day as usual.

The spokeswoman said: “Whilst the county council will be taking action to try and minimise the impact of the action on critical frontline services, it is inevitable that some services will be affected and some school closures are expected.

“Residents are also being warned to expect some disruption across council services.

“The council will not know until the day the full impact of the strike but is working to ensure contingency plans are in place.”

Elsewhere around the county councils have been reassuring residents that they do not expect the widespread strikes to dramatically disrupt services.

A spokesman for Worthing and Adur councils said: “Initial indications are that the majority of services delivered by Adur and Worthing Councils will not be deeply affected by the strike action.

“On the day of the strike, the councils’ leadership team will be closely monitoring service related issues to ensure that customer service standards are maintained as far as possible.

“Some refuse and recycling collections may potentially be affected and if this happens, information will be made available as soon as possible and any collections which can’t be carried out will be made as normal the following week when all waste will be cleared.

“During the strike, your patience will be appreciated if call wait times or email response times are slightly longer than normal.”

A spokesman for Eastbourne Borough Council said: “Current indications are that there will not be significant disruption to any council services. “Additionally, the council has plans and policies in place to ensure that essential services will be given priority in the event that more sizable numbers of staff do decide to take strike action.”

A Crawley Borough Council spokesman said: “We won’t know how many staff will strike until Thursday because they do not have to give advance notice of their intention to strike.

“However, we expect the majority of services will be able to provide a normal service.”

Councillor Jonathan Ash-Edwards, cabinet member for finance and service delivery at Mid Sussex District Council, said: “We are expecting the majority of our staff to come to work as usual on Thursday and therefore any disruption will be kept to a minimum.

“I am confident that we will be able to provide the residents of Mid Sussex with our normal high standard of services.”

A Lewes District Council spokeswoman said: “Lewes District Council will endeavour to continue to provide services where we are able to do so.

“We ask residents to bear with us if we are unable to answer a query as quickly as we would like or where there are some service delays.

“We will keep residents and businesses informed once we have clearer picture on the day via the council’s website, twitter and local media.”

A spokesman for HM Courts and Tribunals Service, which is responsible for criminal, civil and family courts and tribunals, said: “We have robust contingency plans in place which will prioritise the delivery of our most essential services such as custody cases and urgent family cases.

“Our aim is to keep disruption to a minimum and continue to work with all staff to deliver our services to the public.”

A Department for Work and Pensions spokesman, which is responsible for Jobcentres, said a rigorous action process was in place to cope with the anticipated strike and there was not anticipated to be any impact on services to customers.

For full details of affected services and school closures, residents are advised to visit, or