1. Field of play description/requirements

  1. Playing field (Dohyo)
    1. The dohyo shall be not less than 600cm and not more than 727cm square.
    2. The dohyo shall be set on a clay surface or, on combat sports mats overlaid with a smooth, seamless single-layer tarp.
    3. The dohyo can be constructed either at ground-level or elevated to a height of up to 50cm.
    4. The four sides of the dohyo shall be identified as North, South, East and West.
    5. A dohyo shall be installed indoors, unless it is an outdoor dohyo with a roof over it.
    6. A minimum ceiling height of 3.5m is needed, with no objects hanging below this level.
  2. Combat area
    1. The ring area should be marked as a circle in the center of the dohyo area with a diameter of 455cm.
    2. The ring line shall be made of rice bales, called tawara, or a comparable material suitable for delineating a dohyo circle, such as half-cylinder segments of polyethylene foam or other appropriate substitutes.
    3. Four tawara are places slightly outside the perimeter of the ring circle, at the four cardinal points, and these shall be referred to as toku-dawara.
    4. The bales shall be 64cm in length, 11cm in width, and 4cm tall above the surface of the ring.
  3. Shikari-sen
    1. There shall be two dividing lines in the center of the ring named shikari-sen.
    2. The standard length of the dividing lines shall be 70cm apart, 80cm long, and 6cm wide.
    3. The dividing lines shall be painted white.
  4. Peripheral Arrangements
    1. Seats for the judges shall be installed at the four corners of the dohyo.
    2. If the height of the platform requires it, steps shall be installed on the East and West sides. Additional steps may be installed on the North and South sides for convenience.

2. Field of play variations

  1. Clay Dohyo
    1. The inside of the ring circle shall be covered with a thin layer of sand.
    2. A thin layer of sand shall be spread along the outside border of the ring circle forming a fringe 25cm wide.
  2. Tarp Dohyo
    1. The tarp dohyo shall be installed on combat sports mats, overlaid with a smooth, seamless, single-layer square tarp.
  3. Outdoor Dohyo
    1. An outdoor dohyo shall be covered by a roof, such as a canopy.
    2. Competition and practice shall take place in an outdoor dohyo only when weather conditions allow it.