Vacuum cleaner performances are essential for proper vacuum cleaning. When trying to find out if a specific model is good for you, such data is good to know - and reviews of other people, of course.
On the other hand, many manufacturers are using specifications of their vacuums to promote their models as 'just the right model for you' (logically - they want to sell as many vacuums as possible), often hiding certain details that can play key role in deciding if certain model is the right for you.
Vacuum cleaner performances can be measured by various parameters:
- Air speed in meters per second (m/s), kilometers per hour (km/h, kmph) or miles per hour (mph). The faster the air speed, generally stronger 'cleaning' power of the vacuum cleaner, but ... Faster air speed also requires stronger motors, requiring more power, thicker cables etc. To avoid that, many manufacturers keep the air flow speed within certain limits, but use various power tools like spinning brush and similar to increase cleaning effects of vacuums, without increasing motor power.
- Airflow in liters per second (l/s), cubic meters per minute (m3/min) or cubic feet per minute (ft3/m) (one cubic foot equals to 0.0283 cubic meters or 28.3 cubic liters) is amount of air that flows through the vacuum at any given moment. It can be obtained by multiplying the cross section area of cleaning head (or any other part where air flows) and air speed at given point. Larger the airflow, generally stronger 'cleaning' power, but also larger volume of air that needs to be filtered before it is released into the cleaning area. Larger airflow hence requires larger filters, larger and stronger motors, thicker cables ...
- Suction power, which is measured in centimeters or inches of water lifted or in pascals (Pa). This is maximum difference in pressure that vacuum cleaner can create. Typical domestic vacuum cleaner can create suction of 20 kPa (Pascal is a measure of pressure that equals to pressure of 1 newton of force per square meter of area) – 20 kPa would be 20000 N/m2 or around 2 tons per square meter, or around 200 cm (80 inches) of water. More powerful vacuum cleaners generally have more powerful suction.
- Output power is power in watts of the airflow at the end of cleaning hose. Often, this measure is called air-watts. Ratio of output and input power gives effectiveness of vacuum cleaner in percentages (%).
- Input power is consumption of energy of the vacuum cleaner. This is not the actual power of vacuum cleaner due to loses in the system and level of effectiveness in general. In North America vacuum cleaner manufacturers often state the vacuum's current in amperes (for example, '12 amps') and in order to get wattage that must be multiplied by the line voltage (110V). So, '12 amps' vacuum cleaner consume around 1300W of electrical energy.
Note: Line voltage in Europe is 220V, so don't use vacuum cleaners if they are made for different market, unless you have vacuum cleaner that has manual or even automatic voltage switch. As of now, EU limit on vacuum cleaner power is 1600W and from 2017 will be 900W.
Other specifications include parameters not directly related to performances:
- Weight in kilograms (kg) or pounds (lb). One pound equals to 0.453 kg. Lighter vacuum cleaners are easy to maneuver with and often, due to their smaller sizes, can reach tight spaces. On the other hand, they often lack power and filtering capabilities of the larger, but heavier models. Upright vacuum cleaners often have swiveling cleaning heads, enabling them to reach tight spaces despite their sizes and cylinder vacuum cleaners usually have hoses with several add-ons that can reach practically everywhere.
- Noise in decibels (dB) determine noise of vacuum cleaner. Especially silent vacuum cleaners can be used in the room while kids are sleeping, while noisier models will wake up half the city :) Stay away from anything noisier than 80dB (75dB). Vacuum cleaners with noise levels below 60dB are great, but most of them are between 65 and 75dB.
Note: Library or computer noise is around 40dB.
- Power cord length - longer power cord means more freedom when vacuuming and changing outlets less. Most of the models have some sort of automatic winding mechanism, so after vacuuming, power cord is stored in seconds, literally.
- Hose length (if applicable) - enables certain models to reach tight spaces. It is easier to maneuver with vacuum hose with power head than with whole vacuum cleaner. On the other hand, due to air friction inside the hose, power loses are somewhat increased.
Of course, there are other details that influence performances and general characteristics of vacuum cleaners, but they are often specific to individual model of vacuum cleaner.