A playpen can help parents get things done with the knowledge that baby can’t wander off or get into some sort of mischievous. But it’s no substitute for parental oversight.
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Here are suggestions to help you find a safe playpen, courtesy of the Nemours Foundation:

• If you choose a playpen with mesh sides, protect baby’s fingers by making sure the holes are small — 1/4 of an inch or less. The mesh must also be sturdy and properly attached to the device’s edges.
• The sides of the playpen must extend at least 20 inches above the floor.
• The rails on each side should be well-padded to protect baby from a head injury.
• Make sure that your infant can’t reach any of the playpen’s locks.
• All hinges and supports should be enforced and protected.
• If acquiring a used playpen, make sure its floor is in good shape, with no tears or worn spots.