Carlos Sainz believes the presence of the Halo cockpit safety device prevents the detection of light rain, forcing drivers to guess track conditions.
Running at the end of yesterday's session, in damp conditions, the Renault driver said he failed to notice it had started to rain because the Halo had prevented the drops from reaching his visor.
"Today when it started raining a bit, the rain, you couldn’t see it on the visor," explained the Spanish driver Monday evening.
"The Halo was not allowing the rain drops to go onto the visor.
"So you were not really seeing if it was raining or not. You were just feeling it in your hands, in your ass to see how the grip was."
Sainz admits that light rain conditions are challenging as drivers resort to guessing a track's level of grip or rely on information from their pit wall.
"This kind of rain sometimes as drivers it really bothers us because you don’t know if you can actually push 100% or not," he added.
"You have to guess it with the pit wall and see how much rain there was because for us, our visor was completely dry and outside it was raining. So a bit tricky there."
Overall however, the 23-year-old Renault driver insisted he had no issues with the Halo's presence.
"After two laps you don’t see it any more you just see through it," he said.