by Scarlet Palmer on 01/12/2014 | Cultivation

Top five tips for grow room safety

Safety Grow room safety is essential. How do I keep my grow safe and myself too? How do I prevent fires? How do I prepare for a fire, just in case? How do I protect my eyes? How do I lower my chances of catching Legionnaires’ Disease? All these questions and more are tackled below!

1.       Do everything you can to prevent fire.

a.       Don’t leave any trash lying around. A really simple and effective tip is to not have a bin inside your grow room, instead just keep a roll of garbage bags and use a fresh one every time you’re in there, taking it with you when you leave.

b.      Check for anything in your grow room that could catch fire, or burn quickly if it does catch on fire, and get it out of there!  Your grow room should not be used as a storage area, especially for anything flammable. (And definitely don’t store your cannabis seeds in there.)

c.       Install a smoke alarm, and make sure you replace the batteries and test it regularly. Also test whether or not you can hear it from other places in the area or building, as it’s no use if you can only hear it with the door open.

d.      Don’t use a heat regulated thermostat for keeping your room temperature down. They might seem like a good idea for if you’re away frequently, but if a fire does break out, the fans will activate and draw the fire through the ventilation system, feeding it with more air as it goes.

2.       Assume a fire is going to break out at some point anyway.

a.       Keep at least one fire extinguisher in your grow area. Check that it is full and in good working order, and replace it within the ‘use by’ date. Keep a good torch next to it; if your lights are off, and your room is as light-proof as it should be, you may be dealing with a pitch-black space filled with smoke and lit only by flickering flames.

b.      Fit a heavy-duty, preferably fire-resistant door to your grow space, especially if it is in or attached to your home. If you can, have two, with a small area between them; this seriously reduces the speed at which the fire spreads (and is also handy for changing your clothes on the way in and out).

c.       Have an exit plan. In the event of a fire getting out of control, you should already know which way(s) you can leave the building, and what you’re going to do about alerting other people in the area and the emergency services.

Keep at least one fire extinguisher in your grow area
Keep at least one fire extinguisher in your grow area

3.       Know that you can never be too careful with electricity!

a.       Don’t overload your electricity circuits or otherwise stress your cables and power-points. If you have to splice wires, use a proper connector; invest in heavy-duty extension cables with built-in circuit breakers.

b.      Fix ballasts and extension cable blocks to pieces of wood, and then the wood to the walls or ceiling. Keep as many of your electrical components off the floor as possible; not only is this better for fire safety, it’s better for overall safety to keep cables out of the way so you don’t trip over them.

c.       Familiarize yourself with basic wiring safety. This is a good list of the most common DIY wiring mistakes, and what to do about them.

4.       Protect your eyes, lungs and skin.

a.       Your eyes can be damaged by long-term exposure to UVA, UVB and UVC rays. Regular sunglasses with a CE rating of 400 will filter out most UVA and UVB rays, but not UVC. In daylight these rays are usually filtered out in the upper levels of Earth’s atmosphere but they are present in the extreme light spectrums of grow lights. HPS, LED and MH lights will all produce excellent results for plants, but will cause headaches and irritation for gardeners! Invest in a good pair of glasses designed specifically for indoor garden use; Method Seven produce some excellent models and are very popular with professionals.

b.      Your eyes can be far more rapidly and drastically damaged by chemicals. Whenever you are working with nutrients, fertilizers, pesticides and especially pH balancing substances, wear proper safety goggles every single time. Opening a bag of powder can cause it to puff up into the air and mix with liquid on the surface of the eye, forming a corrosive liquid that can even cause blindness, depending on which chemical it is.

c.       Keep an eye bath, or at least a bottle of saline solution, handy for worst case scenarios. It’s much better to have it and never need it, than to try flushing your burning eyes with a watering can. Rinse your eyes for at least 10 minutes; the most damage from chemical burns occurs in the first one to five minutes, so having something on hand will make a big difference.

d.      Protect your airways as well as your eyes, especially when working with chemicals. Use breath masks and full face masks as needed. e.      Invest in a box of latex gloves, and use them. Cannabis can cause skin irritation; even if you haven’t experienced this previously, it has been known to develop with repeated exposure to the plants. Needless to say, always use them when dealing with nutrients, pesticides, pH adjusting agents and other growing substances.

f.        Keep a first aid kit handy, and keep it well stocked! Remember to replace any items that you use up.

Water on the floor is hazardous in various ways
Water on the floor is hazardous in various ways

5.       Remember that water can be as dangerous as electricity in its own way!

a.       Water on the floor is hazardous in various ways: you can slip in it; it can conduct electricity; mould, bacteria and even mosquitos can breed in it. There are several anecdotes of growers who have been seriously ill after contracting Legionnaires’ Disease, which thrives in aquatic systems (including areas of condensation) between 25 – 45 degrees centigrade, and in soil, making it all too easy to accidentally cultivate in a grow room, especially one with high humidity.

b.      Dripping water is even more dangerous, as it can get into your wiring systems and electrical outlets, and will eventually accumulate somewhere and cause further problems (see above). However, condensation from humidity can be a less visible but equally problematic threat. Whenever you are running cables, whether for electricity or hydroponics and especially towards the upper part of the room, be sure to leave a ‘drip loop’, or bend, in the cable. This curve allows condensation to collect at the lowest point of the cable rather than running along it and reaching the plug or the bulb.

c.       Although it sounds obvious, always check that your taps are off and your feed tank (if you’re using hydroponics) is full before you leave. Floods, along with fires, are the two major hazards for growers’ health and safety – and also for grows being discovered. However, feed tanks running on empty can be hazardous too. If your pump is on an automatic timer and your tank has run dry, the resulting loud thumping noise can be annoying for neighbours, and eventually burn out your pump, which can lead to a fire.

We hope you find this information useful, and that it helps to keep you – and your plants – safe. Please let us know if you have further hints and ideas, and share them in the comments; it’s by pooling our knowledge that we can all move forward quickly and effectively, and in this case, more safely!

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I was in the lobby area of a dispensary today for less than 5 minutes (first time ever.) There was no product visable, just a counter and a receptionist, Within minutes of leaving I felt a headache coming on, and although a mild one I'm still feeling it's effects.

I'm starting a job in October where I'll either be in a dispensary, store, or grow house, and I'm wondering if the headache is a coincidence, or if it's common for industry employees?




Dr Cedrickson

Dear Bernie,

Don't worry its quite normal to experience constant headaches whilst working in and amongst cannabis for extended periods of time. Just regularly take plenty of aspirin and load up on extras so you never run out. Try to avoid taking too many and eat plenty of yoghurt to replace bacteria and avoid liver damage.

Kind regards,

Dr Cedrickson



Great post. You can never be too careful with this things...



Any advice on the type of smoke detector? I've got a tent with lights and fans in (and plants, natch), in a room with digi and magnetic ballasts, an AC unit, and the other bits and pieces. I will be getting two detectors, plus a load for the rest of the house otherwise (in this game we can't risk the fire brigade coming out, even for a kitchen fire or something "benign". Prohibition is so stupid that here I am weighing-up delaying a call to 999 in an emergency!).

The heat-change at lights-on time might cause a false-alarm for a heat detector variety smoke alarm. There are differences between the effectiveness of ionising and optical detectors, and I wonder if there is a better variety for a grow room? Maybe the heat detector would actually be best, after-all? There is the contents of the room that matter to a detector type, but I think the extract and air-flow could complicate the decision.

Is there a clever place to put a smoke detector in a grow room? How about pretty much on the extract filter?


Scarlet Palmer

Hi there,

These are all really good questions, and I've made a note of them for the event that we write further articles on grow room safety. I can't really answer them here, but please have a look at the Sensi Seeds forum, where hopefully you will find people who have had the same sort of issue. One thing that I didn't mention in the article and you haven't mentioned in your comment is fire blankets. Since you specify that you need to really need to protect your whole house (which is very true!) having fire blankets in each room or hallway is definitely worth doing.

With best wishes, and good luck!



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