Standard 991, Edition 3
UL 991

Standard for Tests for Safety-Related Controls Employing Solid-State Devices

UL Standard Edition 3 Published Date: October 22, 2004 Last Revision: June 09, 2010


Revisions and Related Documents

Red Line Std. (2)

June 09, 2010 Revision
April 02, 2008 Revision
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Proposals (2)

CSDS Proposal   

CSDS Proposals

An electronic document associated with a UL Standard for Safety or Outline of Investigation, and issued by UL to propose:

  • A revision of a single or multiple requirement(s).
  • A complete new edition of an existing Standard or Outline.
  • A new Standard or Outline that has not previously been published.

CSDS Proposals provide access to view the proposal and submit comments within UL's Collaborative Standards Development System (CSDS) appropriately.


February 16, 2024
September 26, 2023
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UL LLC - Certification Requirement Decision    Learn more about CRDs
April 19, 2007
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Other Updates (0)

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Referenced Standards (0)

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Reverse Referenced Standards (79)

UL 991 is referenced in the following list of UL Standards

82 9 Electric Gardening Appliances
130 13 Standard for Electric Heating Pads
141 9 Garment Finishing Appliances
174 11 Household Electric Storage Tank Water Heaters
197 10 Commercial Electric Cooking Appliances
201 3 Garage Equipment
283 3 Air Fresheners and Deodorizers
295 2 Commercial-Industrial Gas Burners
334 2 Outline of Investigation for Theater Lighting Distribution and Control Equipment
353 5 Standard for Limit Controls
430 8 Waste Disposers
458 6 Power Converters/Inverters and Power Converter/Inverter Systems for Land Vehicles and Marine Crafts
471 10 Standard for Commercial Refrigerators and Freezers
489B 1 Molded-Case Circuit Breakers, Molded-Case Switches, and Circuit-Breaker Enclosures for Use with Photovoltaic (PV) Systems
561 7 Floor-Finishing Machines
710B 2 Recirculating Systems
710C 3 Outline of Investigation for Ultraviolet Radiation Systems for Use in the Ventilation Control of Commercial Cooking Operations
749 12 Household Dishwashers
756 8 Standard for Coin and Currency Changers and Actuators
858A 3 Safety-Related Solid-State Controls for Household Electric Ranges
859 11 Household Electric Personal Grooming Appliances
943B 3 Appliance Leakage-Current Interrupters
963 4 Standard for Sealing, Wrapping, and Marking Equipment
964 12 Electrically Heated Bedding
970 1 Retail Fixtures and Merchandise Displays
987 8 Standard for Stationary and Fixed Electric Tools
1008 9 Transfer Switch Equipment
1008A 2 Transfer Switch Equipment, Over 1000 Volts
1008S 1 Solid-State Transfer Switches
1012 8 Power Units Other Than Class 2
1018 6 Electric Aquarium Equipment
1042 5 Electric Baseboard Heating Equipment
1090 7 Electric Snow Movers
1261 6 Electric Water Heaters for Pools and Tubs
1278 4 Movable and Wall-or Ceiling-Hung Electric Room Heaters
1447 6 Standard for Electric Lawn Mowers
1482 7 Solid-Fuel Type Room Heaters
1559 5 Insect-Control Equipment - Electrocution Type
1647 6 Motor-Operated Massage and Exercise Machines
1699B 1 Photovoltaic (PV) DC Arc-Fault Circuit Protection
1778 5 Uninterruptible Power Systems
1795 5 Standard for Hydromassage Bathtubs
1815 5 Nonducted Heat Recovery Ventilators
1917 5 Solid-State Fan Speed Controls
1973 3 ANSI/CAN/UL Batteries for Use in Stationary and Motive Auxiliary Power Applications
1995 5 Heating and Cooling Equipment
1996 4 Electric Duct Heaters
2006 5 Standard for Halon 1211 Recovery/Recharge Equipment
2021 4 Fixed and Location-Dedicated Electric Room Heaters
2111 1 Standard for Overheating Protection for Motors
2157 4 Electric Clothes Washing Machines and Extractors
2158 6 Electric Clothes Dryers
2161 2 Standard for Neon Transformers and Power Supplies
2202 3 DC Charging Equipment for Electric Vehicles
2264A 2 Outline of Investigation for Water Electrolysis Type Hydrogen Generators
2267 3 Standard for Fuel Cell Power Systems for Installation in Industrial Electric Trucks
2271 3 Batteries for Use In Light Electric Vehicle (LEV) Applications
2271 3 Batteries for Use In Light Electric Vehicle (LEV) Applications
2272 2 Electrical Systems for Personal E-Mobility Devices
2442 2 Wall- and Ceiling-Mounts and Accessories
2523 1 Solid Fuel-Fired Hydronic Heating Appliances, Water Heaters, And Boilers
2565 1 Standard for Industrial Metalworking and Woodworking Machine Tools
2580 3 Batteries for Use In Electric Vehicles
2580 3 Batteries for Use In Electric Vehicles
2594 3 Electric Vehicle Supply Equipment
2750 1 Wireless Power Transfer Equipment for Electric Vehicles
2753 2 Outline of Investigation for Battery Operated Ride-On Lawn Mowers
2790 1 Commercial Incinerators
2849 1 Electrical Systems for eBikes
2850 1 Outline of Investigation for Electric Scooters and Motorcycles
2875 2 Outline of Investigation for Modular Cable System Assemblies and Fittings for Industrial Control, Signal and Power Distribution
3141 1 Outline of Investigation for Power Control Systems
3202 1 Outline of Investigation for Mobile Electric Vehicle Charging Systems Integrated with Energy Storage Systems
5840 1 Electrical Systems of Battery Powered Aviation Ground Support Equipment
9540 3 Energy Storage Systems and Equipment
9741 1 Electric Vehicle Power Export Equipment (EVPE)
1400-1 1 Outline of Investigation for Fault-Managed Power Systems - Part 1: Safety Requirements
2231-2 2 Personnel Protection Systems for Electric Vehicle (EV) Supply Circuits: Particular Requirements for Protection Devices for Use in Charging Systems
60335-1 6 Standard for Safety of Household and Similar Appliances, Part 1: General Requirements
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