Typical burn time range for ~10 cm (4") sparklers: ~10–45 seconds, depending on composition and manufacturer. Cake/wedding “mini” 10 cm sparklers are often rated ~20 seconds; other 10" (≈25 cm) wedding sparklers burn longer (30–45s). Use the manufacturer burn-time spec if you need exact timing.Disposal: after burn, place hot used sparklers in water or on non-flammable surface until fully cooled. Do not leave lying around where children can grab them. Certification & licensing: established manufacturers list PESO / safety registrations on product pages — buy from reputable sellers and check labels.