2022 Nevada Revised Statutes
Chapter 393 - School Property
NRS 393.393 - Assessment of ventilation rates; demand control ventilation system. [Effective through June 30, 2023.]

1. In assessing the ventilation rates of a school pursuant to NRS 393.3915, qualified adjusting personnel or qualified testing personnel, as applicable, shall:

(a) Ensure that the ventilation rates in each room of the facility that is routinely occupied meet the minimum requirements for ventilation rates set forth in the Uniform Mechanical Code;

(b) Calculate the required minimum outside air ventilation rates for each room of the facility that is routinely occupied based on the maximum anticipated rate of occupancy and the minimum required ventilation rate per occupant in accordance with the Uniform Mechanical Code;

(c) Ensure that the minimum outside air ventilation rates meet the required minimum rate calculated pursuant to paragraph (b);

(d) If the minimum outside air ventilation rates do not meet the required minimum rate calculated pursuant to paragraph (b):

(1) Determine whether additional ventilation can be provided without adversely impacting the performance of the filtration system or the environmental quality of the building; and

(2) If additional ventilation can be provided, adjust the ventilation rates to meet the required minimum rate;

(e) If the minimum outside air ventilation rate cannot be met after adjusting the ventilation rates pursuant to paragraph (d), explain why the rate cannot be met;

(f) Conduct survey readings of the inlets and outlets to:

(1) Ensure that ventilation is reaching the served zone and is adequately distributed;

(2) Ensure that the inlets and outlets are balanced to be tolerated by the design of the filtration system;

(3) Document read values and deficiencies; and

(4) If the original values of the design of the filtration system for inlets and outlets of the filtration system are not available, document the available information and note the unavailability of the original values;

(g) Ensure that there is a positive pressure differential between the building and the outdoors, that the building is not overly pressurized and that rooms designated for temporary occupation by sick pupils or staff maintain a negative pressure differential or a pressure differential otherwise set forth by the applicable industry standards;

(h) Ensure that the coil velocities and the coil and unit discharge air temperatures maintain the desired indoor conditions and avoid moisture carryover from the cooling coils;

(i) Ensure that the separation between the outdoor air intakes and the exhaust discharge outlets is in accordance with the Uniform Mechanical Code;

(j) Verify that the air handling unit is bringing in outdoor air and removing exhaust air as intended by the design of the filtration system;

(k) Measure the air volume for the exhaust fans and document any discrepancies in volume between the measurements and the original volume of the design of the filtration system;

(l) Verify that the coil condition, condensate drainage, air temperature differentials of the cooling coils, operation of the heat exchangers and drive assembly meet applicable industry standards;

(m) Review the control sequences to verify that the systems will maintain the intended ventilation, temperature and humidity during school operation;

(n) Verify that daily flushes are scheduled in accordance with the standards set forth by the American National Standards Institute and the American Society of Heating, Refrigerating and Air-Conditioning Engineers and any applicable local or state guidance; and

(o) Ensure that the operation times and set points of the heating, ventilation and air-conditioning system and exhaust fans are in accordance with any applicable guidance set forth by the American National Standards Institute and the American Society of Heating, Refrigerating and Air-Conditioning Engineers and any applicable local or state guidance.

2. Except as otherwise provided in subsection 3, if a demand control ventilation system is installed at a school, qualified adjusting personnel or qualified testing personnel, as applicable, shall ensure that the set point for carbon dioxide is set to 800 parts per million or less.

3. Qualified adjusting personnel, qualified testing personnel or a licensed professional engineer shall disable a demand control ventilation system installed at a school and configure the overall ventilation system to meet the minimum requirements of NRS 393.390 to 393.399, inclusive, if:

(a) The demand control ventilation system does not maintain an average daily maximum carbon dioxide concentration of less than 1,100 parts per million;

(b) The board of trustees of the school district or governing body of the charter school, as applicable, determines that a public health crisis caused by an airborne illness is in effect; and

(c) Disabling the demand control ventilation system would not adversely affect the operation of the overall ventilation system,

until the board of trustees or governing body determines that a public health crisis caused by an airborne illness is no longer in effect.

(Added to NRS by 2021, 1771)