Figure 14
From: First evaluation of a novel ionisation chamber for thermal neutron beam monitoring
The effect of humidity on a monitor response, when electrons and ions drift through air. Here a Honeywell PID is studied, which relies upon a very similar detection and charge collection mechanism as the 
. For typical environmental conditions of relative humidity between 40% and 60%, the signal, that is the output current, degrades by about \(\beta _{\mathrm{humidity}}\approx \)2/3 as a result of humidity. Figure and description adapted from [48]