V. PERSONNEL VI. FACILITIES & ON-SITE CONDITIONS 6.01 Courts A.Court Surface D.Responsibilities 1) Recruit a sufficient number of competent officials for the tournament. Be prepared  to respond to or make recommendations to the Fulltime Official who is coordinat - ing assignments and designations of all necessary and required Chair Umpires. 2) Conduct the necessary pre-tournament training of officials including review of all  appropriate ATP Rules and Regulations. 3) Prepare a list of officials, which shall include the mailing address and national  or local certifications, if any, of all officials used during the tournament. A copy of  such list shall be delivered to the Referee and to the Supervisor. 4) Be on-site at all times during play. The Chief of Umpires may not be a chair or Line  Umpire unless authorized by the Supervisor. 5) Schedule the on-court assignments of Line Umpires for each day of the tourna - ment, subject to the approval of the Supervisor. Line umpires for the quarterfinals,  semi-finals and finals must have worked a minimum of two (2) days prior to the  quarterfinals and have the Supervisor’s specific approval. 5.11 Ball Persons (See ATP Addendum, page 377) Each ATP Tour and ATP Challenger Tour tournament must provide ball persons for all  main draw and qualifying competition matches. Ball persons should be on-site and  available at a reasonable time prior to the first match of the day and there shall be ball  persons available until the conclusion of play each day. A.Number. (See Challenger Addendum, page 398) Six (6) ball persons are recommended per court. B.Clothing  Clothing provided by the tournament for ball persons shall not be solid white, yellow  or other colors that may interfere with the vision of the players, unless otherwise ap - proved by ATP. It is recommended that dark-colored clothing be avoided for outdoor  tournaments played in high temperatures. Clothing should not be identical to clothing  provided to the Line Umpires. 5.12 ATP/GRAND SLAMS/ITF/WTA Code of Conduct for Officials A.  The ATP, the Grand Slam Tournaments, the ITF and the WTA as members of the Joint  Certification Programme require a high standard of professionalism from all Certified  Officials (National, Green, White, Bronze, Silver and Gold) and all other Officials,  (together, “Officials”) working at ATP, Grand Slam, ITF and WTA events. All Officials  are automatically bound by, and must comply with, this Code of Conduct for Officials  (“Code”). The ATP, Grand Slam Board, ITF and WTA shall continue to have jurisdic - tion over a retired Official under the Code and, as applicable, ATP, Grand Slam, ITF  and WTA Tournament Regulations and Codes of Conduct in respect of matters taking  place prior to his/her retirement. The full text of the Code of Conduct for Officials can be found at the following website:  https://officiating.itftennis.com/rules/code-of-conduct-for-officials/. 84 85 1)  Outdoor court surfaces shall be classified as either a) hard; b) clay; or c) grass. 2)  Indoor surfaces shall be Indoor Hard and shall be constructed using an acrylic or  similar surface paint applied on a hard or semi-hard base. 3) Any court surface or change in a tournament’s court surface must be approved by  ATP. 4) A change in a tournament’s court surface will not be considered for approval  without a written petition by the tournament. B.Size, Position and Color of Courts  1)  The Court shall conform to the specifications of the  Rules of Tennis.  ATP reserves  the right to restrict the color of an indoor synthetic court as well as outdoor surfac - es. The lines of the court shall be white. 2)  Courts shall be laid out with the long axis north and south; however, geographic  considerations may modify this orientation in order to minimize the adverse effect  of serving into the sun.  3) Courts shall not be less than 60 feet (18.29 m.) wide and 120 feet (36.58 m.) long.  Center courts should be 66 feet (20.11 m.) x 132 feet (40.23 m.). C.Preparation of Surface  Clay, composition and loose surface courts shall be swept and lines cleaned before  the start of all matches and properly maintained. D.Lighting 1) Minimum Number of Lighted Courts  – Outdoor events a)  ATP Tour Masters 1000. Center Court, two (2) other show courts plus one (1)  practice court. b)  ATP Tour 500. Center Court plus one (1) other show court. c)  ATP Tour 250. No minimum requirement. 2) Intensity  a) ATP Tour Tournaments. Lighting must be evenly distributed on the court  with a minimum recommended intensity of 100 foot-candles (1076 LUX), av - eraged over 15 readings on court.  The recommended minimum lighting for televised events broadcasting in  high definition is an average of 185 foot candles (approximately 2,000 lux).  The light should be distributed across the court evenly with a consistent color  temperature. b) ATP Challenger Tour Tournaments . Lighting must be evenly distributed on  the court with a minimum recommended intensity of 70 foot-candles (750  LUX), averaged over 15 readings on court. 3) High/low ratio . A ratio of the highest to lowest readings should be no greater than  1x2.0 but the recommended ratio is 1x1.5.  4) Light poles.  Light poles should be positioned so that they are evenly distributed  around the court and it is recommended that light pole heights for other than show 