Answer:
In order to protect the face.
Step-by-step explanation:
The grill spaces on a helmet are small in order to prevent objects to enter inside the helmet. This small grill spaces on the helmet protect the face from very small as well as large objects. The main reason for making grill spaces small on the helmet so that we prevent the entering of the ball and avoid injury of the face so that's why we can say that grill spaces are small on the helmet.