Excessive speed for the road conditions, coupled to insufficient awareness of other vehicles and the poor use of mirrors are all considered to be contributory factors.
Ystyrir bod cyflymder gormodol o ystyried amodau’r ffordd, ynghyd ag ymwybyddiaeth annigonol o gerbydau eraill a defnydd gwael o ddrychau oll yn ffactorau sy’n cyfrannu.