Rule presets

Chinese Official (also known as Mahjong Competition Rules)

This rule preset is based on the official rules presented by the China State Sports Commission, initially in 1998 and slightly revised for the later tournaments. The rules are highly pattern-centered and have a high minimum point requirement (8 points). On the other hand, the pattern selection is huge, and the required amount of points can be achieved with several relatively easy hands, as well. Chicken hand is rewarded with 8 points, and considering the number of available patterns, not necessarily the easiest hand to collect: it must consist of four sets from all three suits and a pair of Winds or Dragons, and the suit sets must not form any pattern.

Unlike the Chinese Old Style and New Style Mah Jong, Chinese Official does not use a settling table to determine the final score. Instead, scores for patterns are simply added up (though rules for exclusions are a bit complex). The payoff scheme is similar as in the Taiwanese Mah Jong: if the winner goes out self-drawn, all losers pay the winner directly the amount of his final score. If the winner goes out on a discard, discarder alone pays the amount of winner's final score.

Other features not normally seen in other modern Chinese versions of Mah Jong include abandon of Dead Wall (as to have more available tiles for this demanding version of Mah Jong) and passing of the deal after East's win and after a draw.
Tiles 144 (136 + Flowers and Seasons)
Initial points 500 pts
Limit points Not used (in Four Winds, set to a maximum value of 100,000 pts). 
Note: It seems that the rule has changed recently so that a limit of 88 points is used.
Restrictions for the winning hand Minimum of 8 points required, bonus for Flowers and Seasons ignored when determining the minimum points
Claiming rules for going out Player first in turn wins
Passing of the deal Always when the deal ends (after draw and even when East wins)
Rule of Ready None
Dead hand rules None
Payment To winner only; Chinese Official/Taiwanese scheme + winner always collects the minimum (8 pts) from each loser
Discards Per player, no extended discard information
Specialties No Dead Wall, concealed Kongs are melded face down
Scoring Point-based
Basic tile points None
Scores for basic sets Melded Kong (1 pt); Concealed Kong (2 pts), Terminal and plain Wind triplets 1 pt, Dragon triplets, own Wind and Wind of the Round triplets each 2 pts.
Scores for Flowers and Seasons Points only for single Flowers and Seasons (1 pt for each)
Scores for patterns based on Chows Same Chow from 2 suits (1 pt), Same Chow from all suits (8 pts), Two identical Chows (1 pt), Three identical Chows (24pts), Four identical Chows (48 pts), 123789 of the same suit (1 pt), 123789 twice of the same suit (pair of 5's of the same suit required, 64 pts), 123789 twice of two suits (pair of 5's of the third suit required, 16 pts), Run of 6 tiles of 1 suit (1 pt), 2 runs of 6 tiles of 1 suit (3 pts*), 3 Chows of 3 suits, step 1 (6 pts), 3 Chows of 1 suit, step 1 (16 pts), 3 Chows of 1 suit, step 2 (16 pts), 3 Chows of 3 suits, step 3 (8 pts; Chinese Official exclusions used), 3 Chows of 1 suit, step 3 (16 pts), 4 Chows of 1 suit, step 1 (32 pts), 4 Chows of 1 suit, step 2 (32 pts)
*) 2 runs of 6 tiles of 1 suit (e.g., B123456 C123456) is not explicitly specified in these rules but because of complex exclusion rules used in CO, a player cannot use the components of two runs of six tiles (B123456 C123456) to compose any additional Chow patterns (e.g. B123C123 and B456C456) accordingly two runs of six tiles would give only 2 points. On the other hand, a player is allowed to arrange the above hand as B123456 (a run of 6 tiles), and then use C123 to compose B123C123 and C456 to compose B456C456, which would give a total of 3 points. Accordingly, specifying 3 points for 2 runs of 6 tiles of 1 suit (which automatically implies all possible lower Chow patterns) results in correct scoring.
Scores for patterns based on Pungs and Kongs 2 triplets of the same number (2 pts), Three triplets of the same number (16 pts), 3 triplets in sequence of 3 suits (8 pts), 3 triplets in sequence of 1 suit (24 pts), 4 triplets in sequence of 1 suit (48 pts), Two concealed triplets (2 pts), Three concealed triplets (16 pts), Two Kongs (4 pts), Two mixed Kongs (6 pts), Two concealed Kongs (8 pts), Three Kongs (32 pts), Four concealed triplets (64 pts), Two Dragons (6 pts), Little Three Dragons (64 pts), Big Three Winds (12 pts)
Scores for patterns based on the whole hand Concealed hand (concealed Kongs allowed; 2 pts), Fully concealed hand (concealed Kongs allowed, 4 pts implies Self-drawn last tile; forced scoring, meaning that by nature concealed winning hands get points for Fully concealed when they go out self-drawn, instead of an extra point for going out self-drawn), Chicken hand (8 pts; Flowers and Seasons ignored), Chow hand (No Honor pairs; 2 pts), Pung hand (6 pts), All same upside down (8 pts; implies points for Two suits and Two suits with Honors), All even (18 pts + points for Pung hand), All simples (2 pts), Terminal or Honor in each set (4 pts),  All Terminals and Honors (32 pts; implies Pung hand and points for Pung of Terminals, Kong of Terminals, Pung of Winds and Kong of Winds), Same number in each set (16 pts; the number must be five), All of 1, 2, 3 and 4 (12 pts), All of 6, 7, 8 and 9 (12 pts), All of 1, 2 and 3 (24 pts), All of 4, 5 and 6 (24 pts), All of 7, 8 and 9 (24 pts), No Honors (1 pt), All Suits, Dragons and Winds (6 pts, only for regular hands), Two suits only (1 pt, Honors are allowed), One suit with Honors (6 pts), One suit only (24 pts)
Scores for miscellaneous patterns Four same in two sets (2 pts), Four same in three sets (2 pts), Four same in four sets (2 pts)
Scores for winning Fully exposed hand (concealed Kongs not allowed, 6 pts), Self-drawn last tile (1 pt; implied in Fully concealed hand), Out on 4th of its kind (4 pts), One-chance hand (1 pt), Out on the last tile of the Wall (8 pts Self-drawn last tile implied), Out on the last discarded tile (8 pts), Out on a supplement tile (8 pts only for Kongs, Self-drawn last tile implied), Out by robbing a Kong (8 pts).
Rounding None
Penalties Faulty out: The offender pays 10 points to each of the other players and cannot go out during the rest of the deal; False claims: None; Insurance penalties: None
Limit hands Classical: All Green (88 pts + components), Four Kongs (88 pts + components), Three Great Scholars (88 pts + components; bonus for Dragon triplets implied), Little Four Winds (64 pts + components), Big Four Winds (88 pts + components), All Honors (64 pts + components; Basic winds implied), All Terminals (64 pts + components), Nine Gates (88 pts + components), Thirteen Orphans (88 pts + components); Serpents: Knitted Dragon (12 pts + components; melds allowed); Pairs: Seven pairs (24 pts + components); All Honor Pairs (88 pts + components), All Terminal Pairs (88 pts + components), All Terminal and Honor Pairs (56 pts + components), Consecutive Pairs in One Suit (88 pts + components) Note: Identical pairs allowed; Special ways of going out: None; American hands: None; Miscellaneous: Independent (Knitted; 12 pts + components), Independent with 7 Stars (Knitted; 24 pts + components).

Related topics:
Classification of rules
Alan's Zung Jung
American Classical
American Modern
British Official
Chinese Classical
Chinese New Style
Chinese Transitional
Dutch League rules
EMA Riichi Rules
European Classical
Hong Kong Mah Jong
Internet Mahjong Server
Italian Official
Japanese Classical
Japanese Modern
Japanese Transitional
Korean Style
Mahjong Masters Million
Taiwanese 16-Tile Mah Jong
Wilmington Advanced 12-Tile rules
WMPA Rules
Comparison table