Protection from UV/IR
The degree of protection against infrared and ultraviolet radiation provided by the complete mask light filter.
Such protection is relevant primarily when working with electric welding: it is the electric arc that produces a large amount of IR and UV radiation. Exposure to these types of radiation on the skin can cause burns, and ultraviolet light is also harmful to the eyes. The degree of protection in this case is indicated in DIN units, and the larger the number in such a designation, the higher the degree of protection. In this case, 12 DIN is considered the minimum acceptable indicator, however, masks / goggles can be found on the market with higher protection rates — up to 16 DIN inclusive.
From a purely practical point of view, the higher this level of protection, the better; however, this characteristic significantly affects the price, and sometimes also the weight of the mask / goggles. So when choosing, it is worth considering the features of the planned work. For example, it is hardly worth specifically looking for a model for 15 – 16 DIN, if you have to cook rarely and little by little, but for professional use and large volumes of work, this level of protection will be very useful.
Filter class
Class is a complex indicator that determines the overall quality of the light filter in a chameleon mask (see "Type"). The class is indicated by 4 numbers, each of which describes a specific optical parameter. So, the first number indicates the overall clarity and lack of distortion; the second is the degree of light scattering; third — uniformity of blackout (presence/absence of visible blackout spots); the fourth is the angular dependence (how much the filter brightens when the angle of view deviates from the perpendicular). In each case, the larger the number, the worse this parameter is. The perfect indicator is considered to be 1/1/1/1, but in fact it is very difficult to achieve an perfect angular dependence, and there is no need to. Therefore, an indicator of 1/1/1/2 is considered quite sufficient even for a high-end professional filter.
Filter viewing area (WxH)
The size of the transparent part of the light filter — the "working window", the area through which the welder sees the place of work. A larger working window provides ease of use and a wide field of view, but it significantly affects the cost of the mask and somewhat reduces the strength of the light filter.
Operating temperature
The range of ambient air temperatures at which the mask is guaranteed to be able to function normally. This parameter is especially important for "chameleons" (see "Functions"), because. the performance of the automatic filter directly depends on external conditions (in particular, at low temperatures, the response time may increase).
Sensitivity adjustment
The ability to change the sensitivity of the sensors responsible for the operation of the light filter in the "chameleon". Thanks to this function, you can adjust the filter in such a way that it is guaranteed to turn on from the arc and at the same time does not react to extraneous light sources.
sensitivity adjustment is especially useful when there is numerous extraneous "flare" (for example, when several welders work close to each other, in bright sunlight, etc.).
Delay time adjustment
The ability to manually set the delay time between the disappearance of the arc and turning off the filter in the chameleon mask. Such a delay is highly desirable in the light of the fact that even after the arc is turned off, the heated metal continues to glow for some time; therefore, it is advisable not to turn off the filter immediately.
Adjusting the delay time allows the welder to independently choose the time to return to the non-working (maximally transparent) state.
Design features
— Backlight. Illumination system built right into the mask. This feature is very convenient when working in low light conditions: the backlight does not take up the hands (unlike hand-held flashlights) and does not create problems with wearing a mask (unlike headlamps), while the beam of light is always directed to where the welder's head is turned. On the other hand, such a system requires its own power supply. Therefore, it is used only in "chameleons", while the operation of the backlight additionally consumes battery power.
