1. what does laser class 2 mean?
The accessible laser radiation is in the visible spectral range (400 nm to 700 nm). It is harmless to the eye for short exposure times (up to 0.25s). Additional radiation components outside the wavelength range of 400-700 nm fulfill the conditions for Class 1.
Note: In the case of Class 2 laser equipment, the eye is not endangered by accidental, short-term exposure to laser radiation, i.e. exposure durations of up to 0.25s. Class 2 laser devices may therefore be used without further protective measures if it is ensured that neither intentional looking into the device for use for longer than 0.25s nor repeated looking into the laser radiation or specularly reflected laser radiation is required.
As a rule, the presence of an eyelid closure reflex to protect the eyes must not be assumed: For continuously emitting class 2 lasers, the accessible radiation limit (GZS) is P grenz =1 mW (for C6= 1).
2. with manual mode the laser flashes every few seconds, is it possible to turn it off?
If you lock the laser so that it does not align but remains static, it will blink every few seconds, this is not possible to turn off. Both in automatic mode, when the laser is tilted too much (>4°) and can no longer level itself, and in manual mode, a blink indicates that the projected line is not in the water.
This function only serves as a reminder, as it can happen that one accidentally switches on the manual mode or is at the limit of the levelable range. This is especially useful for small angles where you cannot see the deviation with the naked eye.
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