In the U.S., the tradition of electric lights during the holidays began as early as 1894, when President Grover Cleveland hung the first electrical lights on a Christmas tree in the White House ². Many developments have been made since then as households across the country have adopted the same practice, but some risks and hazards still remain. In the 2022 holiday season in the U.S., about 14,800 people were treated in hospital emergency rooms due to holiday decorating-related injuries, including falls, electrocutions, and burns ¹. One way to reduce holiday fires is to make sure that the decorations themselves do not add to fire risk. Common pitfalls in holiday decoration contribute to the risk of fire and injury. Since 1965, UL Standards & Engagement has been defining stringent requirements for various safety measures related to seasonal and holiday decor, and yet, from education to manufacturing and testing, there is still more to be done so we can all share a safer, brighter holiday season.

UL 588 defines the scope of what a seasonal holiday light or decoration is. A temporary-use, seasonal decorative-lighting product covered by this standard is only to be used for 90 days or fewer in a year. If a light were intended to be used more than that, then it would not be considered seasonal. The standard also identifies the types and parts of seasonal decorations and the restrictions on those parts for safety, including seasonal decorative lighting products and accessories like decorative lighting strands, wreaths, light sculptures, and motorized displays. Over time, UL 588 has changed to provide testing guidance for many temporary and even permanent light styles such as LED lights, rope lights, and year-round outdoor patio lights.

UL 588 provides guidance for the following:

• Safe limits on the strength and rigidity of indoor and outdoor holiday decor enclosures based on their composition (i.e., metallic or plastic)
• Various electrical supply connection types
• Requirements for strain relief in assemblies and wires
• Circuit requirements including every circuit’s battery, switches, wiring boards, lamps (bulbs), lamp holders, and fuses
• Markings for consumer awareness and use

UL 588 provides testing requirements for every safety-relevant component, too. Leakage current, small amounts of electric charge leaving their intended circuit, can cause shocks, so a leakage current test measures any current dissipating from all exposed conductive and insulating materials of the product. Excessive heat from a product could ignite fires if placed near flammable materials by the user, so a temperature test is used to help ensure lamps and other materials do not exceed safe temperature thresholds. A strain test helps ensure that when pulled, the product does not expose any conductive materials which could cause a short circuit or a shock to the user.

In the event of product failure, the downward burning rate test helps ensure that the material used to make the product will burn at a slow rate (no more than 4 inches per minute). Tests for normal and abnormal use and tests for markings and tags support user interactions, helping make sure that the user is informed of appropriate use and that the product is likely to remain safe even if misused. For example, plastic becomes more brittle in colder temperatures, so a cold impact test augments the traditional product impact test to help ensure that a consumer using a decoration in the winter would still be protected by a sturdy enclosure.

In the U.S., the impact of UL 588 being the listing standard for the NEC is regulatory. But regulation is rarely enough — implementation is also crucial, as is adapting to new contexts and technologies.

In 2020, the Philippines’ Department of Trade and Industry’s Bureau of Philippine Standards (DTI-BPS) signed a collaboration and licensing agreement with UL Standards & Engagement to “share information and bolster safety, security, and sustainability of the Philippines.” In December 2022, DTI-BPS adopted UL 588, the Standard for Seasonal and Holiday Decorative Products, which specifically covers temporary light strands and assemblies including stars and light sculptures, like parols. Products in the Philippines can be certified to UL 588 if they meet the strength and rigidity standards to withstand normal use, and if they meet the wire gauge, overcurrent protections (fuses), and linking requirements to help prevent risks of electrical shock and electrical fires.

In addition to adding lanterns, the standard has been revised to acknowledge that products covered by UL 588 might be used year-round, even if a manufacturer advises they are to be used for 90 days or less. To mitigate the increased risk caused by continuous use, UL 588 includes a supplement on string lights for all-year use, listing additional requirements for safety:

• Larger wire gauge size and increased insulation thickness of the wire to minimize overheating and fire hazards, especially when multiple devices are connected in series
• Enhanced flexibility and strain requirements to ensure wires will not break or pull out of insulation during use
• Different safety markings and instructions for year-round use of lit decor.

In addition to regulations, education can help implement safety standards effectively. In the case of the Philippines, ULSE is working with DTI-BPS to educate parol manufacturers on how to construct lanterns that meet UL 588. DTI-BPS is also engaged in educating the public on how to look for the Philippine Standard Mark, indicating the product has met UL 588’s testing standards. In the U.S., education remains an important goal as well. Annual nationwide public service campaigns by the National Fire Protection Association (NFPA) stress the importance of complying with UL 588 restrictions. For example, if a string of lights connects with other strings, knowing how many are safe to string together is essential. The NFPA works to influence safe consumer actions like looking for certification insignia, keeping lights away from heat and flammable materials, and turning off lights at night.

Still, just the existence of an appropriate safety standard and recommendations to look for safety marks does not mean that consumers are guaranteed safe products. Additional oversight helps ensure that when unsafe items come onto the market, they are recalled or eliminated. In the U.S., while retailers often only stock compliant products, there are exceptions. On Christmas Eve 1998, the U.S. Consumer Product Safety Commission recalled about 176,000 Christmas lights for being poorly constructed with undersized wires, no fuses, and wires that could easily be pulled out of the plugs, presenting fire and electrocution hazards [7]. Recalling those strings helped to remove threatening products from the market.