Described herein is a gas detection system (5) including a housing (10) having an inlet (20) in fluid communication with an atmosphere; an analyzer (25) within the housing (20) and configured to detect and measure a gas species in the atmosphere using a gas sensor (37); and a pneumatic system (60) contained within the housing (10) and in fluid communication with the inlet (20) to draw an air sample from the atmosphere. The pneumatic system (60) includes a pump (15); a low flow branch (65) in fluid communication with the pump (15) and having an airflow sensor (90) and a first orifice (85); and a high flow branch (70) in fluid communication with the pump (15) and having a second orifice (95). Such a system is particularly suitable for remote sampling because it prevents the high flow needed for remote sampling to be directed towards the gas sensor withstanding only low flow. Related apparatus, systems, methods and/or articles are described.