Are All Crib Mattresses the Same Size?
Crib mattresses should be firm to avoid suffocation and overheating risks for infants, and waterproof to protect against diaper leakage and spit-up from leading to mold, mildew and other microorganisms that could pose risks for baby health.
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Crib mattresses are manufactured to ensure there's no gap between the mattress and crib edge, decreasing the risk of babies getting caught between limbs and edges of their cribs.
Size
Your baby's crib mattress should fit snuggly in its frame with no more than an inch between its edges and mattress for optimal safety purposes. Any gaps may lead to your infant attempting to climb out and potentially suffocate themselves, thus decreasing chances for potential falls or other accidents.
Crib mattresses are strictly regulated by the Consumer Product Safety Commission and have very small variance in dimensions; there can be up to an variance of 5/8 inch smaller or larger from their standardized 28 inches by 52 38 rectangle depending on manufacturer.
Some manufacturers provide 2-Stage crib mattresses, featuring one firmer side for infants and the other softer for toddlers as they transition into big kid beds. These mattresses may also be made of organic materials certified as GOTS, GREENGUARD Gold or GOLS certified to give parents peace of mind that their child is sleeping on non-toxic materials that meet GOTS, GREENGUARD Gold or GOLS certification criteria; providing parents with peace of mind that their child's sleeping surface doesn't contain chemicals that might otherwise harm him/her while sleeping on conventional foam or innerspring options would.
Firmness
Firm mattresses provide additional resistance when teaching babies to roll over and stand in their cribs, and thus help lower the risk of suffocation.
For testing the firmness of a crib mattress, press down on it with your hand firmly. If it springs back instantly, that mattress should be suitable for your infant; otherwise if an indentation remains, it is too soft and should not be used.
Material selection for crib mattresses is important too. Polyester pads tend to form air pockets that obstruct baby's breathing; cotton or wool (or both) pads make better insulators than cheaper polyester mattresses.
When searching for an innerspring crib mattress, look for one with high coil counts and low steel gauge. Lower gauges indicate thicker wires that make the mattress firmer.
Materials
Your crib mattress's materials will affect its durability and firmness; foam mattresses tend to be lighter and cheaper while innerspring models with coils will carry higher prices tags.
Make sure that the mattress you select for your baby's sleep environment is certified organic to minimize exposure to hazardous chemicals and contaminants. Other certifications worth keeping an eye out for are GREENGUARD Gold which limits chemical emissions, CertiPUR-US, Oeko-Tex Standard 100 etc.
A crib mattress's quality can also depend on its materials used to craft it, which may impact breathability and heat retention. To maximize comfort, look for one crafted with breathable fabrics such as wool or cotton; in-person purchasing allows easier inspection for proper size and firmness inspection as well as noting any visible indentation that could indicate overly soft mattresses that pose a suffocation risk.
Warranty
When purchasing a crib mattress, look for certifications that demonstrate its quality. A CertiPUR-US label on a foam mattress indicates it meets stringent safety requirements – this includes avoiding chemicals like phthalates which have been linked with developmental issues and restricting flame retardants such as PBDEs or TCEP.
Firmness should also be an important consideration, since soft mattresses can increase the risk of SIDS by creating indentions that trap baby's head. Furthermore, it should fit securely within a crib without any large gaps between each corner.
Finally, select a mattress that is easy to maintain and durable – this will prevent stains and odors from building up that could harbor harmful pathogens. Also check for recall lists; Americans can find a comprehensive list of current recalls here while Canadians can do the same here.