I don't remember EVER giving any thought to making the home environment safe for my dog and cats when I was a kid... possibly because my parents had taken care of that step without telling me. But now, it seems to be something that I spend a lot of time doing. There are so many ways that animals can get hurt in a human household! In the two years that I've had animals as an adult, here's what I've found so far - some through experience, some through research.
Houseplants: OMG, EVERY tropical houseplant out there is poisonous to animals, to one degree or another! I do love houseplants, but I have to say that I can't have many of the ones that I would typically have. Dumb cane is out. Peace lillies are out. Porthos and philedendrons are out. As far as I can tell with my research, most ferns are okay, and I have a couple of Boston ferns and a few asparagus ferns. (Asparagus ferns do, I warn you, make your cat throw up if she eats them. I'm looking at YOU, Annie.) Spider plants are okay too, but for some reason I've never been able to keep those alive. Oh, and banana trees. Those are fine too.
What I had to do when we got the cats was put my philedendrons and porthos plants up so high that the cats can't get to them. I have some on top of our china hutch, which the cats are only getting on top of if they sprout wings, and on top of the floor to almost ceiling bookshelf in the living room. And anything kept lower is non-toxic, because Annie WILL sample them.
Plastic bags: This one is a no-brainer; everyone has heard of kids and animals suffocating themselves. I am always super-diligent to pick these up and put them in the closet (they're too handy as used kitty litter holders to just throw away.) I think that most of the animals would ignore a plastic bag, but not Charlotte. She is obsessed with them, and will even forego her evening saucer of milk if I've just brought a bunch in from the grocery store. Suffice it to say, she's only allowed to rub her head on them while I'm in the room to watch her.
Food: Argos has only, to my knowledge, counter-surfed once, in his first week with us. We reprimanded him and he's never done it in front of me again. But I'm super-careful to make sure that no food is left on the counters when we leave him unattended. Not even if it's in a plastic bag, like bread. Especially if it's in a plastic bag. I also take the stove knobs off, but I think that I can probably stop doing that. He's never shown any interest in the stove, so even my paranoid self is starting to accept that he's not going to turn on the gas and burn down the house while we're gone.
Easily swallowable items: If we're leaving Argos alone, this means that I have to do a sweep of the downstairs to make sure that the cats haven't left any kitty toys lying around, that there isn't a pair of socks on the floor, and that I haven't left any wash cloths out and about. Argos has a "thing" for white items, which does include wash cloths and socks. For the cats, I just have to make sure that I haven't left any of my yarn out - Bit has a nasty habit of eating it... several feet of it. She has gone to the emergency vet TWICE because she ate yarn and had two feet of it hanging out of her backside by the time we caught on. (Okay, to my credit, she did it with my yarn the first time, then I started putting it under lock and key. The second time she went up to the attic and drug a spool of string/twine that we didn't even know we had out of a box and off of a shelf.)
Trash: Our trash can latches on the top, and you have to push a button to make it pop open. But I'm still really leery about leaving Argos alone with the kitchen trash, which must smell delicious to his canine nose. So it gets locked in the downstairs bathroom if we're leaving.
Litter box: Since we put the cats upstairs in the bedrooms, and Argos downstairs in the common rooms, I can shut away the downstairs litter box so that Argos isn't tempted to go fishing for "tootsie rolls." It doesn't take any extra effort: we keep it under the sink in the downstairs bath, which is already closed off to prevent trash-diving.
Chemicals: (If you read this before and chemicals weren't listed, it was because I forgot them. Duh.) None of our animals have ever gone for the chemicals. But just in case, those are shut into the closet or otherwise put out of reach as well.
Luckily, Argos is not a chewer, so we haven't had to worry about him going after power cords, pillows, couch cushions, etc. I know that some dogs are, and geez. I don't know how people deal with that. I think if he did make a habit of chewing, he'd HAVE to be crated while we were gone.
And as long as I can keep Annie away from plants, Bit away from yarn, Charlotte away from plastic bags, and Argos away from little white objects, they're pretty low-maintenance. (I'm not leaving Romeo out because I'm forgetting him, but he hasn't really gotten into anything truly dangerous. Though he will shred and eat newspaper if we don't feed him quickly enough. That can't be good for him.)
So did I forget anything? What have YOU had to do to dog or cat-proof your house?