154.1838—Discharge by gas pressurization.
         The person in charge of cargo transfer may not authorize cargo discharge by gas pressurization unless:
    
    
    
        
        (b) 
         The pressurizing medium is the cargo vapor or a nonflammable, nontoxic gas that is inert with the cargo; and
    
    
    
        
        (1) 
         A pressure reducing valve that has a setting that is 90 percent or less of the tank's relief valve setting; and