With Consumer NZ voicing concerns at the variability of results from testing sunscreens – here's some tips on how to choose an effective suncreen.

Consumer NZ this year tested a range of sunscreens, including children's products, with eight products failing either the Sun Protection Factor or broad-spectrum tests.

Now the organisation is calling for annual testing of sunscreen products and auditing of labs.

Consumer NZ CEO Sue Chetwin says another issue is for Kiwi consumers is sunscreens here are classified as cosmetics, so don't require approval before they can be sold.

Companies are encouraged to sell sunscreens that comply with the Australian and New Zealand standard. But products that don't meet any standard can legally be sold here.

Consumer reckons making sunscreens a therapeutic product, like in Australia, and ensuring they meet the Australian-New Zealand standard should be a priority.

In the meantime, here's some tip on how to buy effective sunscreens:

• Look for sunscreen with an SPF of at least 30+, plus water resistance and broad-spectrum protection
• Apply sunscreen at least 15 minutes before going out in the sun
• Apply plenty – about one teaspoonful for each arm, leg, back front and face (35mls for a full body application)
• Mopping up sweat or towelling dry will reduce your protection – apply another coat straightaway
• Sunscreen is only one part of your defence against harmful UV rays. Limit your time in the sun and wear cover up clothing.