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Dyson DC 40 Allergy review: Dyson DC40 Allergy

Whether you have allergies or just like a really, really clean floor, the Dyson DC40 will make sure every nook and cranny is pet-hair and dust-mite free.

Michelle Starr Science editor
Michelle Starr is CNET's science editor, and she hopes to get you as enthralled with the wonders of the universe as she is. When she's not daydreaming about flying through space, she's daydreaming about bats.
Michelle Starr
3 min read

In the years since Dyson released its first vacuum cleaner in the early 1990s, the company has had a lot of time to perfect its cyclone machines — and it's come a long way, as evidenced by the DC40 Allergy.


Dyson DC 40 Allergy

The Good

Powerful suction Lots of attachments for a variety of surfaces Easy to figure out Space-age design Easy-to-find controls.

The Bad

Heavy Hose is stiff and awkward Ball head can't get under low furniture.

The Bottom Line

Whether you have allergies or just like a really, really clean floor, the Dyson DC40 will make sure every nook and cranny is pet-hair and dust-mite free.


Like pretty much anything that comes out of Dyson, the upright DC40 is a futuristic-looking beast of a machine. Naturally, it sports the clear dust chamber that Dyson pioneered, with colour highlights in red, gunmetal grey and metallic blue — resembling, for all the world, some kind of homage to the art of house cleaning.

The hero feature, according to Dyson, is the massive ball above the cleaner's head, which allows it to rotate in difficult directions to clean hard-to-reach areas.

The box also comes with a selection of heads that attach to the hose, which is tucked away in the cleaner's handle for an alternative to the ball head.

Putting the machine together wasn't difficult, but there are a lot of pieces involved — you will find that you probably need to use the instruction manual initially.


If you're used to a 15-year-old Electrolux dinosaur that your mum picked up for you from Godfrey's, then a Dyson vacuum cleaner is a bit of a culture shock. For starters, the DC40 is a lot heavier than it looks — so the handle on the cyclone chamber came in handy when it came to hauling it from room to room when using the hose.

As it turns out, the ball does allow the head a good degree of manoeuvrability, which is great for getting into poky, out-of-the-way corners, and the suction is strong and steady enough for picking up all but the most stuffed-into-the-skirting dirt.

With that colour scheme and "DC" in its name, we couldn't help but think of him. We don't mean to imply that Superman is a vacuum cleaner. Sorry, Superman.
(Credit: Dyson; DC; CBS Interactive)

However, the ball itself is, well, large, and it won't fit under furniture such as low beds, chair rungs and low-hanging shelving. This is where the auxiliary hose comes in, with a variety of different heads for floors, corners and upholstery. Switching between modes (ball head or hose) is intuitive; unclip the cleaner from the upright rest position to use the ball head, and put it back to activate the hose.

It's important to note at this point that this reviewer's cat sheds more hair than it actually has. This should be physically impossible, but figuring out how cats work is a job for far deeper thinkers. Suffice to say that a cat that rains hair over every surface does not mix well with a velvet bedspread.

The DC40 Allergy claims to be great for people who are sensitive to pet hair and other allergens, and the allergy person in the household noted that it was much easier to breathe after a vacuum. Using the upholstery attachment, the aforementioned bedspread was clear of cat hair in very short order, and dirt that had remained in mats after previous vacuum cleans was picked up in one sweep.

The hose itself was a little stiff; we assume that it would gain a bit of flexibility with more use, but removing and clipping in the extra heads was easy to figure out and allowed for under-furniture reach that the ball head can't manage.

Emptying the dust chamber when done is simple, too. Simply unclip the chamber, hold it over your bin and press the release button. Unless your dirt is a big, soggy mess, it will fall out cleanly without raising a dust cloud or getting your hands dirty.


Whether it's an allergen-free environment or just a super-clean floor that you're seeking, the Dyson DC40 Allergy is a fiend of a machine that does a magnificent job of picking up dirt you never even knew you had.