Our test included ...

Light output: for sensor security lights and garden spotlights we measured the total amount of light (lumens) produced by each unit. For garden lights, including bollards (tall cylinders) or stick lights, we measured the amount of lumens produced in one direction per square metre (lux) at a range of distances up to 1.5m from the lens.

Electrical safety: we looked at the quality of electrical construction and the insulation of live wiring from any external metal parts.

Construction robustness and water resistance: assessed by examining the appearance and construction materials of the units, then hosing them down for 10 minutes before checking for any water in the lens.

Maximum range of motion-detecting PIR (passive infra-red) sensor.

Installation time: for mounting sensor lights on the wall assuming the wiring is already in place.

Endurance: For the solar garden lights we measured their light output at regular intervals throughout the evening after charging on both sunny and cloudy days, then checked if they were still going just before dawn. Solar security lights are assessed after charging on a sunny day then activating them up to 20 times, before running them continuously and measuring how long until they switched off.