In Portugal, Volunteer FDs can only use Yellow for regular firefighters, Red for team leaders and White for commanders. The Professional FDs use Black for all firefighters, except for the watch/station managers, officers, commanders etc. that use White helmets (sometimes with additional stripes in other colors).
We use yellow Pacific F7s for most of our calls, red/yellow MSA Gallet F2s for wildfires and blue/red modified MSA Gallet F2s for EMS Operations (we have 3 of these per ambulance).
Lisbon's Professional Fire Brigade (RSB Lisboa) has been using the Rosenbauer Heros in black with white stripes (with the FF ID number on the sides and, sometimes, its rank and name). RSB's paramedics use the same helmet model as the USAR teams (lighter than the fire helmets and more exposed), in white/blue with the ID number and name on the sides. The thing is, when RSB paramedics that aren't on ambulance-duty (basically, they are firefighters with additional training that can also respond to regular FD calls), their fire helmets have a white Star of Life on the sides.
Our team-leaders use red Pacific F7s and RSB watch managers, officers, etc. use white Rosenbauer Heros with red stripes (and sometimes with its rank written on the side "Watch Manager", "Operations Commander" or something like that, it really depends).
Our public EMS (INEM) uses yellow helmets with "INEM" on the sides.
Pics:
These pictures were taken during a training exercise in Chiado, last year.