Haw. Code R. § 12-240-3
Call buttons in elevator lobbies and halls shall be centered at approximately forty-two (42) inches (1065 millimeters) above the floor. When situations prohibit mounting at forty-two (42) inches, in conjunction with ICC A117.1-2009, hall buttons maybe be mounted between fifteen (15) inches and forty-eight (48) inches for unobstructed forward reach, and between twenty-five (25) inches and forty-eight (48) inches for obstructed forward reach. Such call buttons shall have visual signals to indicate when each call is registered and when each call is answered. Call buttons shall be a minimum of three-fourths (3/4) inch or nineteen (19) millimeters in the smallest dimension. The button designating the up direction shall be on top as shown in Figure 240-1, titled, "Hoistway and Elevator Entrances", dated December 6, 1990, which is made a part of this chapter, and located at the end of this chapter. Buttons shall be raised or flush. Objects mounted or placed beneath hall call buttons shall not project into the elevator lobby more than four (4) inches or 100 millimeters.
Haw. Code R. § 12-240-3