Tight-fitting pajamas are less flammable because fires need oxygen to burn. So if there is no air between the child's skin and the fabric, the fire gets less oxygen.

Do pajamas need to be flame retardant?

To this day, pajamas for kids age 9 months through size 14 must be flame resistant or fit snugly. ... The Consumer Product Safety Commission confirmed that it is aware of just one flame-retardant chemical used occasionally on loose, all-cotton pajamas.

What does flame retardant do to your body?

There is growing evidence that many flame retardant chemicals can affect the endocrine, immune, reproductive, and nervous systems. Some animal studies have shown that long-term exposure to flame retardants can lead to cancer.