Its mad the way times have changed so much, standards were different back a few years.
My mother left me on my own (with the placid dog) for a whole week whilst she went away, albeit only 1hr half away but still went away for 7 days. my care file shows the police, school and SS discussed but no action was taken 
and I was left to it and my mother to my knowledge never had any consequence from that.
I on the other hand have had ss round for allowing my oldest child go to the park round the corner from my house alone at 6 ( I live rurally with not a lot of traffic to put that in context), they took no action but they still came out and did a initial assessment 
Regardless I feel I know best, I also know my children better than anyone else, nowadays I leave my sensible 9yr old(and more mature than my 11yr old) alone for 10 mins while my 5 yr old is fast asleep(and will have been for several hrs at the point)in bed whilst I pick up the oldest from a club that finishes late evening. he is fine, knows not to unlock and answer the door, cant get into kitchen as it locks with a lock that requires a key so no access to gas, cooker, kettle etc and just sits playing pc.
I wouldn't leave either oldest children with younger one if younger was was awake though.
I think its very dependant on the individual child, I completely understand why some people bauk at the idea of a 14 yr old alone whilst others are happy to leave younger ones. my middle child is far more sensible and wise than the oldest who is 2 yrs older, he doesn't take risks, hes very cautious, very safety aware, the oldest however is the complete opposite, risk taker, impulsive etc
I think a sensible approach is to think about it carefully when planning to leave a child alone, whats the worst they could do? what do they have access to? can they contact you?