Dell P26S Owner's Manual page 61

Relative Specifications
humidity
(maximum)
Operating 10 % to 90 % (non condensing)
Storage 5 % to 95 % (non condensing)
Altitude Specifications
(maximum)
Operating –15.2 m to 3048 m (–50 to 10,000 ft)
0° to 35°C
Non-operating –15.24 m to 10,668 m (–50 ft to 35,000 ft)
Airborne G2 or lower as defined by ISA S71.04–1985
contaminant level
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