A big change in policy on how the Yakima Fire Department responds to emergency calls. The department is no longer sending fire trucks on every call for emergency medical services.   Dispatchers will decide whether a call can be handled by an ambulance.  The fire department says three-quarters of it's emergency calls require only paramedics. Yakima Deputy Fire Chief Bob Stewart says "running trucks to every bloody nose or sore foot wears them out.  Trucks and firefighters will be saved for critical emergencies.