(See Note A-2.4.2.5.) (See also Note A-2.2.8.3.)
(1)
Farm buildings housing livestock with below-floor storage of liquid manure shall be provided with a ventilation system that supplies outdoor air at a rate that is
(a)
sufficient to limit the concentrations of dangerous goods classified as flammable gases to not more than 25% of their lower explosive limit,
(b)
sufficient to limit the concentrations of dangerous goods classified as toxic gases to those permitted in the ACGIH’s “Industrial Ventilation: A Manual of Recommended Practice for Design,” and
(c)
not less than 2 air changes per hour. (See Note A-2.4.2.5.(1))