Power consumption
Rated power consumed by the device during operation. Usually, it is indicated by the maximum power consumption when used in normal mode, without abnormal situations.
In general, this parameter is secondary when choosing: manufacturers select power in such a way as to provide the necessary indicators of performance, pressure, etc. However, some practical points are also associated with power. So, with the same performance (see "Steam intensity"), a more powerful device will spend less time heating water and generating steam; it can also be provided with a more capacious boiler (see "Water boiler volume"), which is useful for long-term continuous operation. On the other hand, such devices turn out to be more expensive, and often also heavier and larger than relatively “weak” steamers, and besides, they load the mains more.
The second point related to power is just the calculations of the load on the wiring and various electrical equipment (protective automation, AVRs, generators, etc.).
Steam flow
Steam flow provided by the device. For models with power and/or humidity adjustment, this item indicates the maximum possible value.
When choosing according to this indicator, it should be borne in mind that the steam flow characterizes only the amount of water vapor produced by the device per minute. The intensity of the impact of this steam on the treated surface/product can be different, first of all, it depends on the working pressure. Therefore, only devices with similar pressure indicators can be directly compared by this indicator. When making these comparisons, it's worth assuming that higher steam flow allows to handle a large amount of work faster, but requires more powerful heaters and larger tanks – which, in turn, affects the dimensions, weight and price of the entire steamer.
Heating time
Heating time until steam is generated. The duration of the heating process directly depends on the power of the device and the volume of the water tank.
We also note that in some situations the actual heating time may be less than the declared one. For example, if the main tank (boiler) is not completely filled, and the design does not provide an additional tank for cold water. For a full guarantee, you should still focus on the value directly stated in the specifications.
Overheat protection
A protective system that turns off the unit if the heater (or other part of the structure) reaches a critical temperature. This can happen, in particular, due to lack of water in the tank or due to a failure of the control electronics.
Overheating protection allows you to avoid such situations with their unpleasant consequences — from a device breakdown to a fire.