When designing you always have to consider safety first.

Here is some simple advice that people either don’t know or pass by. It mainly concern nurseries and toddlers, but you can find it useful even for older kids.

Crib

Cribs must be bought from trustworthy sellers or manufacturers and comply with safety regulations. If safety regulations are not provided or are not clear contact the manufacturer.
Check if the crib model you wish to buy has ever been recalled and if that is the case check why it was recalled.
Cribs with sides that can be lowered are no longer considered to be safe and must not be used.
Crib slates or spindles must be spaced no more than 60mm.
Use appropriate fitted mattress. No more than two fingers width between the edge of the mattress and the crib side. Also check if the manufacturer specifies the mattress height.
Check regularly for loose screws, missing, cracked or splintered parts.
The crib must not be placed near windows.

Furniture

All furniture must be anchored. This is the most ignored safety instruction which can lead to serious injuries.
Heavy items must be stored on the lower part of shelving systems and bookcases in order to avoid injuries in case of fall.
All toys must be within the reach of children.
Storage must not have a cover and if it does it must be lightweight and easily removed by a toddler. Locks are completely forbidden.
Don’t use floor lamps. They can easily tip over.

Cords

If using a baby monitor, it must be placed at least 90cm away and not inside, above or next to the crib.
Cords attached on roman shades or blinds are responsible can lead to strangulations and must be placed out of the reach of children.
Remove mobiles above crib when the baby is able to sit up.

Two extra tips:

Always follow exact manufacturer instructions.
If not sure about the mattress dimensions, give the seller the crib gap dimensions. They will provide you with the right mattress dimension.