Privatising airport security could compromise systems "critical" to safety, a union representing staff says.
Transport Minister Simeon Brown has put out a discussion document which suggests he is looking into privatising the Aviation Security Service (AVSEC).
E tū union spokesperson Michael Wood, himself a former transport minister, told Nine to Noon on Tuesday privatisation would undermine safety.
"Having appropriate aviation security is one of the most safety critical things of the system, and the prospect of privatising those services does compromise them," Wood said.
"We, alongside other unions, have real concerns about this and staff are extremely concerned about what this might mean for the safety of everyone who uses our airports."
He said it was important for AVSEC to remain separate from commercial interests.
"This is complex and skilled work... it's enormously important. These people are trained and they have statutory powers. The current model under AVSEC is that basically they do one thing - their sole focus is on ensuring we have a safe and secure aviation system."
If security was privatised, Wood feared competing interests could lead to lacklustre safety measures.
"If they were airports or airlines who could deliver these services... [They] have an interest in other operational matters," he said.
"If things are running late, that costs airlines a lot of money and that starts to bring other incentives into the system, other than the safety of ensuring everyone is appropriately screened and that process is done well."
Wood said privatisation could lead to lower wages, which he said was a safety risk in itself.
"The experience of the privatisation of these sorts of models is that there is then always a squeeze down on the paying conditions of the workers. In the long run that has an impact on the safety of the system because you end up with poor morale... high turnover."
And it could lead to higher costs for travellers.
"Central government pays for all the expensive capital investment that goes in, things like the walk-through metal detectors, X-ray screening, etcetera," he said.
"Under this model those costs would need to be met by providers, and then they would presumably over the long run have to fund the cost of that out of the levy passengers pay as well."
Brown told the New Zealand Herald he wanted to make the boarding process more efficient and cost-effective.
"People travelling through airports expect a reliable and efficient aviation security service that is secure and can quickly scale up during times of peak demand."
He said airlines could do it themselves at smaller airports "which only screen a limited number of flights each day".
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