N.M. Code R. § 20.11.21.17
Current through Register Vol. 35, No. 12, June 25, 2024
Section 20.11.21.17 - DETERMINATION OF VENTILATION INDEX CATEGORYA. PB-I and PB-II prescribed burns are allowed to be ignited only with a ventilation index category rated "good" or better, unless a waiver has been granted by the department. The ventilation index category may be obtained by contacting the department, or the burner may make the determination by calculating and documenting the ventilation index category using the following methodology: (2) select the appropriate zone for the location of the burn project within the New Mexico map showing the various zones;(3) examine the forecast and find the reference elevation to be used to determine the general ventilation index category for the Bernalillo county zone (e.g., Albuquerque - 5,300 feet above mean sea level or Mountainair - 6,500 feet above mean sea level);(4) record the mixing height for "today" or "tomorrow" as appropriate;(5) calculate the mixing height at the burn location by adding the forecasted mixing height and the reference elevation obtained above. From the sum of these two items, subtract the elevation of the burn location; and(6) calculate the ventilation index for the prescribed burn by multiplying the mixing height at the burn location by the average forecasted transport wind speed. B. Once the ventilation index for the prescribed burn has been calculated, refer to the following table to see if the ventilation index for the burn project is acceptable to ignite the burn: Category | Knot-Feet |
Excellent - Acceptable | Greater than or equal to 150,000 |
Very Good - Acceptable | 100,000 - 149,999 |
Good - Acceptable | 60,000 - 99,999 |
Fair - Not Acceptable | 40,000 - 59,999 |
Poor - Not Acceptable | Less than or equal to 40,000 |
N.M. Code R. § 20.11.21.17
20.11.21.17 NMAC - N, 12/31/03; A, 7/11/11