Consumers should check the gap between the IKEA VYSSA crib mattress and the side and end of the crib. If the gap is greater than 3 cm, the mattress may be returned to any IKEA store for an exchange or full refund. For further information, consumers may contact IKEA Canada toll-free at 1-800-661-9807 or visit IKEA's website . How to measure: Let new mattresses air for 72 hours after unpacking. It takes 3-4 days for the mattress to assume its proper shape and volume. Remove all bedding, for example fitted sheets. Push the mattress into one of the corners of the crib and measure the gap between the mattress and the crib's side and end using a measuring tape. Any gap should be less than 3 cm. Health Canada would like to remind Canadians to report any health or safety incidents related to the use of this product or any other consumer product or cosmetic by filling out the Consumer Product Incident Report Form . Date modified: 2014-09-04