An annual conference among Asian nations against chemical weapons opened here Monday to discuss appropriate responses and countermeasures in case of incidents involving chemical-warfare agents, according to Seoul\'s defense ministry. About 30 experts from 20 nations, including China and India, are taking part in the five-day conference of the 7th Regional Assistance-And-Protection Course for Asian States Parties, the ministry said in a statement. Jointly hosted by the ministry and the Organization for the Prohibition of Chemical Weapons (OPCW), the conference is also aimed at facilitating the exchange of information and experiences among Asian nations regarding pacts under the Chemical Weapons Convention, an arms control treaty that outlaws production, stockpiling and use of chemical weapons, it said.