Consider this before buying your next vacuum

There’s nothing like an old, wheezing vacuum cleaner to make you appreciate how important a properly performing appliance is to your cleaning regimen. The good news is today’s models not only remove dust and dirt, they also tackle more challenging household irritants, such as pet hair and allergens. Here are several issues to consider buying a vacuum.

FLOOR TYPE

For homes with more carpets and rugs than hard floors, upright vacuum cleaners with roller brushes that reach deep to loosen dust and dirt are best. If you’ll be vacuuming several kinds of carpet, look for a model that switches between low- and high-pile settings. If you’ll be vacuuming carpeting and hard floors, choose a model that lets you turn off the roller brush (this will ensure that you don’t scratch wood, tile or other surfaces).

For woolen and delicate carpets and rugs, use a vacuum cleaner that has only suction (such as a stick vacuum or one that lets you turn off the roller brush).

Canisters are best if you will be primarily vacuuming hard floors. They’re also better than uprights for vacuuming stairs and getting under furniture and into other hard-to-reach areas. And they’re easier to carry, making them ideal for multilevel homes.

Canister attachments: Depending on the surfaces you plan to clean with a canister, you may have to use multiple attachments: a floor brush with bristles (but no moving parts) for hard surfaces; a turbo or power nozzle with a roller brush for pile carpeting; and a carpet and hard-floor nozzle with a smooth bottom for hard surfaces and Berber or natural-fiber carpets (sisal and sea grass, for example), which might be damaged by bristles or a roller brush. Note that attachments may need to be purchased separately.

AMOUNT OF SPACE

If you live in a small house or an apartment, you can still reap the 12-amp power of a full-size vacuum in a compact or lightweight design. Compact vacuums typically include a telescoping hose, which makes them easier to store. They generally weigh less than 12 pounds, and they’re easier to navigate under beds and around furniture.

If you live in a large house, you will want the benefits of a full-size vacuum cleaner. Not only will it make a larger swath with each pass, but the greater dust capacity means you won’t have to change bags or empty dustbins as often. Remember to look for a model with the automatic-cord-rewind option.

AIRFLOW AND SUCTION

Rugs and carpets that are subjected to heavy foot traffic require a vacuum with superior airflow and suction. Airflow is measured in cubic feet per minute. Most vacuums have an airflow of 60 CFM to 80 CFM; that number can be much higher in machines of superior quality. Suction is measured by a vacuum’s “water lift” — how many inches of water could be lifted through a tube if it were attached to the vacuum hose. A water lift of 80 inches to 100 inches is considered good. Many manufacturers don’t advertise these numbers, though; you may have to do some research on the Internet or consult a salesperson.

AIR QUALITY

In recent years, the vacuum cleaner’s role in controlling indoor air quality has become increasingly important. Most manufacturers now offer models with HEPA (high-efficiency particulate air) filters, which are guaranteed to capture 99.97 percent of dust and allergen particles, measuring 0.3 microns and larger, including pet dander. Filters should be replaced every year.

Filters installed in a sealed environment, sometimes referred to as “true HEPA,” ensure that dust and allergens won’t escape through gaps in the vacuum cleaner’s frame.

Allergy sufferers should avoid bagless vacuums, because dust and allergen particles can become airborne during the process of emptying the dustbin.

PETS

A mini or handheld turbo brush — included with some models, but also available separately — is essential for removing hair and dander from your pet’s favorite upholstery (the sooner this is done, the better). You may also consider cyclonic suction, which spins debris away from the filter preventing hair from building up.

Yet another filter option, “active HEPA,” uses charcoal to remove odors from the vacuum’s exhaust.

DUSTING

Most vacuums come with basic accessories, including a crevice tool, a round dust brush and an upholstery attachment. Optional extras include a handheld turbo brush (for stairs and napped upholstery fabrics), telescoping duster (for crown molding and ceiling-fan blades) and edge cleaners (whiskers on the sides that clean close to baseboards).

Send questions to Ask Martha, care of Letters Department, Martha Stewart Living, 11 W. 42nd St., New York, NY 10036. E-mail to mslletters@marthastewart.com.

&Copy; 2008 Martha Stewart Living