NOTAM contains information concerning the establishment, condition or chang in any aeronautical facility, service, procedure or hazard, the timely knowledge of which is essential for peronnel concerned with flight operations. The text of each NOTAM contains the information in the order shown in the ICAO NOTAM Format and is composed of the signification/uniform abbreviated phraseology assignned to the ICAO NOTAM Code complemented by ICAO abbreviations indicators, identifiers, designators, call sign, freguencies, fiqures and plain language. NOTAM is originated and issued for Bangkok FIR and is distributed in five series identified by the letters A,C,J,H and G as follows;

Series A - NOTAM containing information on Thailand International Airports and ATS routes according to circumstances. Distribution: International.
Series C - NOTAM containging information on Thailand International Airports, domestic airports and ATS routes according to circumstances. Distributioni: Domestic.
Series G - NOTAM concerning the status of elements of the global navigation satellite system (GNSS.) Distribution: International and Domestic.
Series H - NOTAM containing information of concern VIP Flight in Bangkok FIR Distribution: International and Domestic.
Series J - NOTAM containing information of concern to scope warning (W) activity near or affecting Controlled Airspace or ATS routes according to circumstances. Distritbution: International and Domestic.