Tex. Educ. Code § 37.0021. Use of Confinement, Restraint, Seclusion, and Time-Out.

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(b)  In this section:      

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    (3)  "Time-out" means a behavior management technique in which, to provide a student with an opportunity to regain self-control, the student is separated from other students for a limited period in a setting:

    (A)  that is not locked; and                                                
    (B)  from which the exit is not physically blocked by furniture, a closed door held shut from the outside, or another inanimate object.