 
            
	
                Red Line
                
                March 11, 2022
            
         
        
            
                UL 228
            
            
            
	
                UL Red Line
                
                
                Edition 5
                Published Date: March 11, 2022
                
                
                DOD Approved: October 03, 1994
                
                
                    Scope
                    
                        002280-000000-0000001 Scope
1.1 These requirements apply to swinging door closers equipped with integral electromechanical or electromagnetic holders and which may be provided with integral smoke detectors.  These requirements also apply to electromagnetic door holder units which are for use with a separate door closer and separate automatic fire detector.
1.2 When integral smoke detectors are provided with the combination door closer-holder, the smoke detectors shall comply with requirements for smoke detectors of the photoelectric or combustion products type.
1.3 Requirements for the installation of these combination door closers-holders with or without smoke detector units are included in the Standards for Fire Doors and Fire Windows, NFPA 80, and National Fire Alarm Code, NFPA 72.
1.4 The combination door closers-holders (with or without integral smoke detectors) described in this Standard provide one of the following types of hold open functions:
- a) Single point hold open. 
- b) Multiple point hold open.  (Two, three, four, etc. discrete hold open points as set at the manufacturer's plant.) 
- c) Infinite hold open points with one as set by the user.