Up to 500 ambulance personnel have started a planned strike as part of an ongoing trade union dispute.

The work stoppage, which will continue until 5pm, forms part of an ongoing dispute over trade union representation rights and the deduction of union subscriptions at source from their pay.

The staff concerned, who are members of the National Ambulance Service Representative Association (Nasra), are scheduled to hold further work stoppages on Thursday, February 28th and Friday, March 1st.

Members of Nasra already held a 10-hour work stoppage at the end of January.

The HSE said on Thursday it now anticipated the stoppage would take place as scheduled on Friday and it was putting in place contingency arrangements to apply for the duration of the planned strike.

The HSE also said the focus of its national ambulance service was “to ensure that service and care delivery is not compromised in any manner,” and that the Department of Defence would be providing a number of Army ambulances crewed by military personnel on Friday.

It said managers who were qualified paramedics would be carrying out front-line duties.

It maintained the trade union Siptu, which represented most front-line ambulance staff, had said it expected its members to work as normal and that the Psychiatric Nurses Association (PNA) had confirmed that it would not be calling upon members of other unions to participate in the strike.

The HSE also said that the PNA had confirmed that emergency cover would be provided where necessary.

Nasra is a branch of the PNA and the union’s general secretary Peter Hughes said the escalation of the industrial action demonstrated the resolve of ambulance personnel “to be represented by the union of their choice, and not by a trade union that the HSE wants to force them to join”.

A spokesman for the PNA said the strike was going ahead as planned .

The HSE defended its stances in relation to Nasra and said ambulance personnel were well represented through agreed industrial relations processes.

“Recognition of other associations or unions would undermine the positive engagement that exists and would impair good industrial relations in the National Ambulance Service. It is a well-established principle of public policy that fragmentation of union representation in the public sector is not in the interests either of the public or of workers. For that reason, where grades of employee already have strong representation rights – as is the case in the National Ambulance Service – it is not appropriate for employers to recognise break-away unions. Recognising break-away unions has a destabilising effect on good industrial relations.

“The principle of engaging only with recognised trade unions has been acknowledged previously by the Labour Court in a dispute involving the PNA and a different public-sector employer. With this in mind, National Ambulance Service will stand by the agreements that it has made with recognised unions and will not undermine those agreements by engaging with other associations or unions. This approach is in keeping within Government policy and supports the consolidation that is happening within the wider trade-union environment.”