While homebrewing isn’t exactly one of the more dangerous hobbies in the world, hazards do abound: Emergency room visits from a shattered glass carboy, scaldings, hair set on fire, electrocutions, back thrown out, etc. The good news is that these are not common, and with some common sense and a few simple homebrewery SOPs (standard operating procedures), these can be further minimized.
1) Limit your consumption — Just because you’re making a lot of beer, doesn’t mean you should be simultaneously consuming a lot (especially if you’re driving somewhere afterwards!). During my short stint as an assistant professional brewer, we never had a beer on brew day until the last kettle was drained. When we saw the trub at the bottom of the kettle, we did what we called the trub dance, then went and poured ourselves a pint. It makes the cleaning process a little more palatable. I still (for the most part) adhere to that to this day. Many homebrewers will wait until all clean up is done before having a drink, which I admire. I’m not that disciplined.
2) Closed-toed shoes are a must — I probably should say pants here too, but at the bare minimum, brewers should be wearing closed-toed shoes while brewing. Boots or other waterproof (or at least water resistant) shoes are preferred. A little boiling wort/liquid spilled on your bare skin is extremely painful. The same goes for whenever you are handling glass carboys: Washing, moving, or simply carrying while empty. Dropping a glass carboy (empty or full) can have life-changing consequences if you’re in sandals or flip-flops.
3) Wear a good pair of brewing gloves — I always recommend wearing brew gloves whenever transferring, opening/closing valves, changing connections, scrubbing down kettles, or any other process where your hands are apt to touch hot, caustic, or acidic things. They’re not expensive and a good pair lasts years (mine are twelve years old and still in good shape). To me they’re essential to all beer brewers.
4) Simple electrical and gas considerations — Each carries their own risks but a few rules can eliminate most safety risks. When it comes to propane and natural gas, keep outdoor (high-powered) burners outside or in well-ventilated spaces indoors. I have heard reports from a homebrewer who sustained carbon monoxide poisoning when using his burners in a finished garage with a side door open. That’s not ventilating . . . two doors open with a fan blowing air outside one of them is ventilating.
All DIY electrical builds should be reviewed and approved by a certified electrician. But even if you are simply plugging in a pump for a liquid transfer, you need to make sure all electrical components near your homebrew setup are protected by a GFCI (ground-fault circuit interrupter). Stand-alone GFCI plugs can be purchased at hardware stores and are not expensive. If you accidentally spill a bucket of water onto your pump, the GFCI will protect you from electrocution.
5) Minimize heavy lifting — The recent push towards brewing indoors has been a major upside for homebrewers’ backs. Brewing and fermenting in the same space means a lot less hauling of large volumes of wort/beer. Add in the assistance of a pump(s), and pretty much all heavy lifting can be minimized if you plan well. Don’t try to be a hero . . . be smart and be safe.
6) Zero bottle bombs — A bottle bomb is simply a bottle of beer that explodes . . . hopefully not close to anyone. It sends glass shards flying at high velocity in all directions (and causes a mess). For those that bottle their beers, there are five main causes of bottle bombs: Using the wrong bottle types, bottling too early, a miscalculation in priming sugar, unwanted microorganisms, or a phenomenon known as hop creep. Your standard 12 oz. (355 mL) crown-cap bottle is suitable for all beers except highly carbonated ones. If you are going for a Belgian tripel at say 3.5 volumes of carbonation, you should opt for Belgian-style or Champagne-style bottles. Also, make sure the beer is fully fermented and has had time to settle prior to bottling. The yeast should not be finishing primary fermentation in the bottle (unless you’re an advanced brewer and this was in fact your intention).
I always recommend using a trusted priming calculator and that you double check all your work. Then it’s a classic instance of: Measure twice, add once. If using a sugar other than glucose or sucrose, such as honey or maple syrup, make sure you are taking into consideration what percentage sugar by weight they actually are (although this is more often a source of under carbonation).
Poor sanitation is a common cause of bottle bombs. Be sure you follow a regimented cleaning and sanitation protocol for things like fermenters, racking canes, and reused bottles. Finally there’s hop creep. To prevent this you can either not get super aggressive with dry hops on beers you plan to bottle or give the beer extra time in the fermenter. I personally say about 4 oz. (113 g) or less dry hops per 5-gal. (19-L) for beers you plan to bottle.
7) Protect Your Eyes — Finally, be smart about eye protection. If you’re running beer line cleaner (a harsh caustic) through your taps, protect your eyes from possible spray. If you’re using a counter-pressure bottle filler, wear some face protection. Weak bottles can fail under higher pressures and, just like with bottle bombs, send shards flying.