Christmas Light Safety FAQs
Do Christmas lights cause fires?
Yes, unfortunately Christmas lights can cause fires and lead to fatalities at a higher rate than other fires. That is why it is important to follow instructions that come on your Christmas lights and avoid overloading your electrical circuits. The National Fire Protection Association reports that 40% of Christmas tree fires were caused by Christmas lights, and Christmas lights cause additional fires in other areas in and around the home. Between 2011 and 2015, one out of every 32 reported home Christmas tree fires caused a fatality, compared to an average of one death per 143 reported home fires.
Are Christmas lights safe?
Christmas lights are safe if the electrical wiring and electrical panel in your home are working properly, lights are used according to instructions, electrical circuits are not overloaded, and you follow holiday light safety best practices. It is important to keep your Christmas tree well watered to slow the progression of a fire in the case that your Christmas tree catches on fire.
Is it safe to use outdoor Christmas lights indoors?
Yes, it is safe to use outdoor Christmas lights indoors, as long as the voltage required is safe for your electrical circuits. However, you should never use indoor Christmas lights outside your home. They are not designed for exposure to moisture and could start a fire outside the home.
Are outdoor Christmas lights safe in the rain?
Outdoor Christmas lights that are rated water resistant or waterproof are safe in light rain. If there is water pooled on the ground and your lights are touching it, this is a hazard regardless of the type of lights. Always protect the electrical outlets from rain, and do not touch cords of Christmas lights that are submerged in water.
Is it safe to leave string lights on all night?
You should avoid leaving string lights on all night, as they are not designed for continuous use. Overheating of Christmas lights can be a fire hazard.
Why do my outdoor Christmas lights keep going out?
If your outdoor Christmas lights are continually going out, it could mean that your electrical circuit is overloaded. Call a licensed electrical to help you troubleshoot the source of the problem and correct it, since it could be a safety issue that could cause a fire or electrical emergency. If only some of the lights go it, you likely have a missing or broken bulb on your string of lights.
How Many Strands of Christmas Lights Can You Connect?
Connecting multiple strands of lights is common during the holidays, but there is always a limit to how many you can safely plug into one another. Exceeding that limit can cause overheating, blown fuses, dim lights, or even a tripped breaker. At Palmer Electric, we see this issue every season, especially with older incandescent strands.
a. Follow Manufacturer Instructions
Every light set is designed with a specific maximum number of strands that can be safely connected end to end. Always check the packaging or the tag on the cord, since different brands and bulb types vary.
As a general guide:
- Incandescent lights: usually safe for 3 to 5 strands connected together
- LED lights: often safe for 15 to 50 strands, depending on the brand and wattage
LEDs use far less power, which is why you can connect more of them without overloading the circuit.
Most light strands also have small built in fuses inside the plug. If you exceed the safe limit, these fuses will blow to protect the wiring. If your lights suddenly go out, this is often the reason.
b. Never Mix Bulb Types
Do not mix incandescent and LED strands in the same chain. They draw different amounts of power and are not designed to operate together. Mixing types can ruin the bulbs, blow fuses, or cause overheating.
c. Choose Matching Brands and Series
It is safer to stick to the same brand and product line when connecting multiple strands. Why? Different manufacturers use different electrical loads and connection styles. If you mix them can cause uneven brightness or early failure.
d. Be Mindful of Distance and Extension Cord Limits
The longer the total run, the more resistance you create in the wiring. This can dim your lights or put stress on the first strand in the chain. If you are decorating a larger area, split the load across two outlets or circuits instead of running everything in one line.
| Light Type | Typical Strand Length | Max Strands You Can Safely Connect | Notes |
|---|---|---|---|
| Incandescent Mini Lights | 50 to 100 bulbs | 3 to 5 strands | Highest heat output, higher wattage, easiest to overload |
| Incandescent C7/C9 Bulbs | 25 bulbs | 1 to 2 strands | Large bulbs draw more power, often have very low connection limits |
| LED Mini Lights | 50 to 100 bulbs | 15 to 50 strands | Very low wattage, cooler operation, safest option for long runs |
| LED C7/C9 Bulbs | 25 bulbs | 10 to 20 strands | Designed for longer connections, ideal for rooflines and large displays |
| Commercial Grade LED Strings | Varies | Up to 50+ strands (check manufacturer) | Built for large displays, safest for high count installations |
| Icicle Lights (Incandescent) | Varies | 2 to 3 strands | Incandescent icicles pull more power than people expect |
| Icicle Lights (LED) | Varies | 10 to 15 strands | Lower power draw allows more strands safely |
Important Reminders:
- Always check the manufacturer’s tag or packaging for exact limits.
- Never mix LED and incandescent strands in the same chain.
- If a plug, connector, or cord feels warm, reduce the number of connected strands.
- Outdoor displays often require shorter runs due to moisture and temperature exposure.
At Palmer Electric, we always recommend choosing LED lights whenever possible. They stay cooler, use far less power, and allow for safer, longer connections during your holiday setup.