Dear Nico, What is the best guard against fires while using these high intensity lighting devices? Can a lower wattage bulb be used? Thanks and keep up the good work! — Rollo, via

Greetings, Rollo and thank you for your thoughtful question. The first step in any safe grow operation is asking the right questions!

Today, most HID bulb and ballast manufacturers produce lights that are extremely safe for use indoors. Most are specially designed for large agricultural projects such as greenhouse growers and bio-dome food farms. That being said, the dangers lie in human error within our grow facilities. The primary cause of indoor growroom fires is faulty wiring (more on this below). This is why I always caution growers to solicit the help of experienced electricians when building indoor gardens. This is especially important when wiring power boxes, installing sub-panels or new circuits, or dealing with a building’s main power line.

With that said, there are also a couple of other precautions that indoor gardeners can take to protect themselves and their property. For starters, always keep all wires off the floor and securely attached to walls and ceilings. Keeping wires organized by bundling them with zip-ties is also recommended.

Second, whenever possible keep ballast banks outside of both your growroom and your wet room. Not only does this help prevent heat build-up and provide a better climate for your plants, but it is always smart to separate electricity and water. Many advanced growers keep the ballasts outside the garden (usually above the ceiling) and also have a separate room for their water source, reservoirs, and nutrient-mixing station.

Digital ballasts are organized on a wall outside of the growroom.

Digital ballasts are organized on a wall outside of the growroom.

As far as using lower wattage bulbs in your ballasts goes, this can be very dangerous! Ballasts are made for a specific wattage and bulb type. Using the incorrect wattage other than what is listed on the ballast can cause a ballast to malfunction, possibly leading to a fire. Most ballasts are also designed for a single type of light bulb, usually either a metal-halide (MH) or a high-pressure sodium (HPS). Some ballasts, called “convertible ballasts,” are made to accommodate both types of bulb with a simple flip of a switch, which can be handy if you do both your vegetative and flowering stages in the same growroom.

These ballasts sit atop a grow tent; notice the wood shelf used to keep the heat off the tent material.

These ballasts sit atop a grow tent; notice the wood shelf used to keep the heat off the tent material.

Lastly, I want to impress upon all cannabis growers out there once again the importance of using certified, professional electricians when conducting any sort of serious electrical work. If you are running more than a few lights, you need to consider your power draw and how much amperage your room circuits and wiring can handle. Besides repeatedly blowing fuses, you can cause fires by overloading current on circuits and small-diameter wire gauges. Finding an electrician that smokes weed isn’t as hard as it sounds (trust me, just ask around) and a few nugs can go a long way in ensuring your growroom is safe and secure!

Thanks for reading everyone and remember: Grow… And help the world grow, too!

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