Dimensions of nasal CPAP interfaces and mean expiratory limb pressure at flows of 6, 8 and 10 L/min
| Interface | Size | Prong length (mm) | Internal diameter (mm) | Outer diameter (mm) | Expiratory limb pressure (cmH2O) at varying set flows | ||
| 6 L/min | 8 L/min | 10 L/min | |||||
| Hudson | 0 | 11.5 | 2.0 | 3.6 | 3.69 | 7.84 | 15.53 |
| 3 | 14.9 | 3.5 | 5.1 | 0.47 | 0.94 | 1.95 | |
| 5 | 16.1 | 5.0 | 6.3 | 0.14 | 0.34 | 0.73 | |
| RAM | Preemie | 7.5 | 2.0 | 3.1 | 6.55 | 10.86 | 19.01 |
| Newborn | 7.4 | 2.5 | 4.5 | 5.95 | 9.37 | 14.45 | |
| Infant | 7.9 | 3.0 | 4.7 | 4.53 | 7.07 | 10.91 | |
| F&P prong | Small (3020) | 15.2 | 2.0 | 2.8 | 6.13 | 12.23 | 22.52 |
| Medium (4030) | 17.1 | 3.0 | 3.9 | 1.02 | 1.95 | 3.44 | |
| Large (5040) | 17.5 | 4.0 | 4.8 | 0.22 | 0.46 | 0.83 | |
| Infant Flow prong | XS | 11.0 | 2.5 | 3.3 | 0.33 | 0.71 | 1.27 |
| M | 13.3 | 3.5 | 4.3 | 0.25 | 0.53 | 0.92 | |
| XL | 16.9 | 4.0 | 5.1 | 0.25 | 0.55 | 0.93 | |
| Height* (mm) | Width* (mm) | Length* (mm) | |||||
| F&P mask | Small | 4.2 | 6.6 | 4 | 0.00 | 0.00 | 0.00 |
| Medium | 4.2 | 6.6 | 4 | 0.00 | 0.00 | 0.00 | |
| Large | 4.2 | 6.6 | 4 | 0.00 | 0.00 | 0.00 | |
| Infant Flow mask | XS | 5 | 5 | 1.2 | 0.18 | 0.40 | 0.68 |
| M | 5 | 5 | 1.2 | 0.18 | 0.42 | 0.68 | |
| XL | 5 | 5 | 1.2 | 0.19 | 0.42 | 0.71 | |
*Mask measurements indicate the dimensions of the airflow channel at connection to the CPAP circuit (the narrowest point of the device) rather than the dimensions of the nasal mask itself.
CPAP, continuous positive airway pressure.