42 CFR §88.17

1. (a)A physician affiliated with either a CCE or NPN will promptly transmit to the WTC Health Program a determination that a member's exposure to airborne toxins, any other hazard, or any other adverse condition resulting from the September 11, 2001, terrorist attacks is substantially likely to be a significant factor in aggravating, contributing to, or causing the illness or health condition, including a mental health condition. The transmission will also include the basis for such determination. The physician's determination will be made based on an assessment of the following:
   1. (1)The individual's exposure to airborne toxins, any other hazard, or any other adverse condition resulting from the September 11, 2001, terrorist attacks.
   2. (2)The type of symptoms experienced by the individual and the temporal sequence of those symptoms.
2. (b)For a health condition medically associated with a WTC-related health condition, the physician's determination must contain information establishing how the health condition has resulted from treatment of a previously certified WTC-related health condition or how it has resulted from progression of the certified WTC-related health condition.