抄録
The octane number requirement (ONR) for recent gasoline vehicles in Japan has been surveyed using a primary reference fuel (PRF) for octane number measurement and a commercial type fuel (CTF). The ONR for regular gasoline recommended vehicles has hardly changed since 1997, but the ONR for premium gasoline recommended vehicles has slightly increased. The ONR measured with the PRF, which has zero sensitivity (RON-MON=0), and that measured by the CTF with a high sensitivity for 1997 to 1999 model year vehicles are quite similar in terms of RON. On the other hand, the ONR measured with the PRF is smaller than that measured with the CTF for 2006 model year vehicles, which shows that MON also affects the ONR of recent vehicles.
