The American Academy of Pediatrics recommends newborn nursery environments not exceed an hourly average of 45 dBA, with momentary peaks below 65 dBA. SafeSonic applies this directly to the 0–3-month band. Source
The University of Toronto infant sleep-machine study recommends no more than 50 dBA at the infant's ear during sleep, with sound sources kept at least 2 m from the cot. Source
WHO community-noise guidance recommends bedrooms stay below 30 dBA for good-quality, restorative sleep — SafeSonic's "Ideal" zone. Source
The US EPA identified a 70 dB 24-hour average as the level preventing any measurable hearing loss over a lifetime — the ceiling for the older awake bands. Source
NIOSH sets 85 dBA (8-hour, 3-dB exchange rate) as the occupational exposure limit. SafeSonic treats ≥85 dBA as hazardous at every age. Source
The WHO-ITU safe-listening standard allows children and sensitive users (all under-18s) a weekly sound dose equivalent to 75 dBA for 40 hours, and adults 80 dBA for 40 hours (3-dB exchange). The "safe time at this level" figure is computed from the allowance for the selected age. Source
| Age | Sleep limit | Awake limit | Peak alert |
|---|---|---|---|
| 0–3 mo | 45 dBA* | 60 dBA | 65 dBA* |
| 3–6 mo | 50 dBA* | 65 dBA | 70 dBA |
| 6–12 mo | 50 dBA* | 65 dBA | 75 dBA |
| 1–2 yr | 55 dBA | 70 dBA* | 80 dBA |
| 2–4 yr | 60 dBA | 70 dBA* | 80 dBA |
| 4–12 yr | 60 dBA | 70 dBA* | 80 dBA |
| 13–17 yr | 60 dBA | 70 dBA* | 80 dBA |
| Adults | 60 dBA | 70 dBA* | 80 dBA |
* Values marked with an asterisk come directly from published guidance (AAP, Pediatrics 2014, EPA, WHO-ITU). Unmarked values are conservative interpolations between published anchors — stated transparently because no body publishes thresholds for every age band. 85 dBA is always treated as hazardous, at every age (NIOSH).
Phone microphones are not laboratory instruments — readings can vary by ±5 dB or more between devices. For best accuracy, compare SafeSonic against a calibrated sound-level meter in a steady noise environment, then adjust the offset until the readings match.
Tip: a quiet bedroom at night typically measures 25–35 dBA; normal conversation at 1 m is roughly 60 dBA.
SafeSonic is an informational tool, not a medical device, and does not diagnose, treat or prevent any condition. Smartphone microphone readings are estimates; the app is deliberately conservative, but it cannot replace a calibrated meter or professional advice.
If you have concerns about your child's hearing or sound environment, consult a paediatrician or audiologist. Never leave a phone inside a cot or within an infant's reach.