最近在靠北排球FB專頁上看到相關的討論,
想起以前學生時代也常碰到這個問題,
所以再次本版舊文並補充相關資料,以利想了解的人查閱。
FB原文： #靠北排球9083 https://0rz.tw/bMDzW
相關回文 #靠北排球9086 https://0rz.tw/uwNi1
#靠北排球9092 https://0rz.tw/jqJeQ
FIVB英文規則原文：
12.5 SCREENING
12.5.1 The players of the serving team must not prevent their opponent,
through individual or collective screening, from seeing
the service hit and the flight path of the ball.
12.5.2 A player or a group of players of the serving team make(s) a screen
by waving arms, jumping or moving sideways
during the execution of the service, or by standing grouped,
in order that both the service hit and the flight path of the ball
are hidden until the ball reaches the vertical plane of the net.
Should either be visible to the receiving team this is not a screen.
中文版（香港總會版本）
12.5 遮擋 SCREENING
12.5.1 發球隊的球員不得在發球時，以個人或集體遮擋方式，
阻礙對方注視撃球和球的飛越路線。
12.5.2 發球時，若發球隊的一名球員或一組球員揮動手臂、跳起、側向移動，
或以集體站位的方式，掩護撃球和球直至飛越網頂的路線，即為遮擋。
若發球撃球或球的飛越路線能被接發球隊見到，則不是遮擋。
FIVB Guidelines-Instructions 2024中提及的部分：
The 1st referee should pay attention to screening during the execution
of the service when a player or group of players of the serving team,
waving arms, jumping or moving sideways or by standing grouped,
prevent their opponent from seeing the server and flight path of the ball
until the ball crosses the vertical plane of the net.
So if the served ball can be seen clearly throughout its path,
until it crosses the net to the opponent, it cannot be considered as a screen.
Referees must be more zealous in taking care of the teams' intentions
to create a screen and prevent from the beginning of the game that the teams
abuse the screening rule with the excuse of "tactical strategy."
Therefore, when a team is CLEARLY GROUPED with the intention of screening,
or players are with hands above head height (they may, however, protect their
heads for safety reasons but must not rise their hands above the head),
the referee can indicate this to the serving team, by blowing his/her whistle,
to separate the players, and, if they do not do so,
the 1st referee MUST CALL THE SCREEN after the service.
It is necessary that ALL referees apply these instructions
from the beginning of the matches,
to reverse this trend that affects the fair play.
另外補充,
引用一本絕版的書籍《排球裁判執法實務要領》,作者：蔡崇濱、陳進發。
掩護的類型及成立條件與說明
https://imgur.com/ME6UUxP
書中所附範例一
https://imgur.com/sL27o6E
範例二
https://imgur.com/yNEAKeO
範例三
https://imgur.com/P8LUXqo
（靠北排球FB原文那個案例應該近似於此範例）
總結：
大體上來說掩護（遮擋）發球（SCREENING）的規則是明確的,
之所以一直讓人有種像是灰色地帶的原因似乎是實務執法時鮮少有裁判適用
（FIVB的指引中也有提到裁判須適時地闡明,並對於指示後仍違反者判罰）,
也可能是實戰時使得違規的條件成就機率相對不高
（例如即便對方站位阻擋視線,我方接球員也會挪移）,
亦或者,通常在適用該規則判罰前,主審通常也會給予指示提醒。
其餘相關的規則說明詳如上附資料。