Minimum specifications from the IHOG for Helicopters:
TYPE 1
5,000 lb allowable payload (sea level, 59 degrees F)
15 or more passenger seats (standard category)
700 gallons retardant or water capacity
12,501 lb. maximum gross take off and landing
TYPE 2
2,500 lb allowable payload (sea level, 59 degrees F)
9-14 passenger seats (standard category)
300 gallons retardant or water capacity
6000-12500 lb. maximum gross take off and landing
TYPE 3
1,200 lb allowable payload (sea level, 59 degrees F)
4-8 passenger seats
100 gallons retardant or water capacity
Up to 6,000 lb. maximum gross take off and landing