This section explains how we calculate the claims we make in our advertising. Where we can, we test our products in accordance with IEC guidelines using standard IEC62885-2 - these are official international standards for comparing vacuum cleaners. If there are no suitable test standards, we use real homes and record real-life data. Data sample size varies - we test in at least 10 different households and up to 50 if it is practical to do so. Finally, if neither of the above is suitable, we will set up laboratory testing to try and replicate real-life usage.

How do Gtech work out Pro bag usage per year?

All homes have different cleaning schedules (and levels of dirt and dust), but we do our best to offer the most accurate results possible. We conduct user home trials and record how long a bag lasts in different households, from those with pets to family homes with young children. From that, we calculate the average number of bags that would be used in a full year.

Our calculations show that the average number of days a bag took to fill was 49.6 - this would require 7.4 bags per year, dependent on the size of area cleaned and amount of debris.

Some homes with rigorous cleaning routines and 4 inhabitants (and pets!) filled their bag in around 3 weeks; others used the same bag for a couple of months. We chose a wide range of household styles and cleaning routines to replicate those of real-life customers.

Highest number of days: 64

Average per unit: 49.6

Bags needed per year: 7.4

Tests are still ongoing - results will be updated as we discover more.

What makes the Pro battery ‘professional grade’, what do Gtech mean by 'a design life of 10 years' and how is that calculated?

It’s important to us that we use the best possible components in our products. That’s why we’ve gone for LG Lithium-ion batteries - they’re reliable and robust, two of the most important elements for professional users.

We can’t test our batteries for 10 years before we launch a product - this is unrealistic for any brand. Instead, we do an accelerated-use test in our labs to see how long the batteries last in real-life simulations. This involves continuously charging the batteries and then letting them run down while monitoring their performance.

Our batteries maintain 88% of their performance after 1000 cycles. If we charge and run down a battery once a week, the battery would last for up to 19.2 years. If we do this twice a week, the battery would last for up to 9.6 years.

These figures may vary depending on home type and usage, and our testing shows that cleaning time and charging varies significantly.

How do Gtech test the Pro’s runtime?

We test all of our floorcare products in accordance with IEC standards (international guidelines that all floorcare manufacturers have to follow). When used in ‘Eco’ mode, the Pro can run for an average of up to 40 minutes when used for above the floor cleaning; when used in ‘Max’ mode (recommended for tougher challenges), the average runtime is up to 20 minutes.

The Pro’s runtime will be a bit longer when the bag starts to fill up and when you use it in handheld mode. This is because there’s less air resistance and strain across the vacuum’s fan, so less power is needed. The runtime may be slightly shorter if you’re only cleaning carpet, especially if it has a thick pile.