An average sized adult should be using a least six full teaspoons of suncream to be fully protected.
The Health Products Regulatory Authority has issued a warning to people to make sure they are using the right amount of suncream and to ensure products are not out of date.
It said people need to apply the product at least 20 minutes before being exposed to the sun and it needs to be reapplied every two hours.
The HPRA says no suncream will give 100% protection, but if you use the right amount and the product is not past its usage date, you will be protected from harmful UVA and UVB rays.
Skin cancer is the most common form of cancer in Ireland.