Sources: NOAA NCEI 1991–2020 normals for Tucson airport; manufacturers’ manuals linked below. HHZ didn’t test any devices; the limits below come from manufacturers’ manuals.
Tucson temperatures (airport, 1991–2020)
| Month | Normal high | Normal low |
|---|---|---|
| May | 91.8°F | 61.8°F |
| June | 101.2°F | 71.1°F |
| July | 100.2°F | 76.3°F |
| August | 98.6°F | 75.2°F |
| September | 95.1°F | 70.4°F |
Station elevation: 776.9 m (about 2,549 ft).
Device limits
| Device | Operating temperature | Operating humidity | Source |
|---|---|---|---|
| ResMed AirSense 11 | 41–95°F | 10–95% RH, non-condensing | User guide |
| ResMed AirCurve 11 | 41–95°F | 10–95% RH, non-condensing | User guide |
| Inogen Rove 4 / Rove 6 | 41–104°F | 15–90%, non-condensing | Rove 4, Rove 6 |
| CAIRE FreeStyle Comfort | 41–104°F | 15–95% RH, non-condensing | Manual |
| Oxlife Independence | 50–104°F | 10–95% at 82.4°F | Manual |
Practical steps
| Situation | Guidance from the documents |
|---|---|
| CPAP at night | Normal summer lows are well inside the 95°F limit; use air conditioning |
| POC outdoors at midday | Keep within the 104°F operating limit; seek shade and cool breaks |
| Device left in a car | Storage ranges go to 158°F (AirSense 11, Rove 6); operation doesn’t |
| Dry air | Within humidity ranges; see CPAP dry mouth |
| Summer outages | Power outage plan |
Verdict
Tucson’s summer daytime heat exceeds CPAP operating limits, so keep equipment air-conditioned and plan outdoor oxygen use around the hottest hours.
Related: Phoenix heat guide, Las Vegas heat guide, El Paso guide.