How are lasers classified?

In order for users to recognize at once in broad strokes the risks involved in using a particular type of laser, hazard and risk classes have been created to which each laser must be assigned and labeled.

There are 8 classes created, they are defined as Class 1, Class 1M, Class 1C, Class 2, Class 2M, Class 3R, Class 3B and finally Class 4.

The less powerful and relatively harmless lasers are assigned to Class 1, at the opposite extreme the class of lasers that are definitely always dangerous is Class 4, in each intermediate class are included the various types of lasers according to power and danger to people and property.

It is important to have a good understanding of the risks and dangers involved in using each kind of laser.

A summary description of the risks and dangers they pose is given for each Laser Class, however it is also good to behave according to common sense and in addition to observing the prescriptions always take reasonable precautionary measures as well.

In general, therefore, it is advisable to always keep in mind that lasers are always dangerous, even if included in Class 1, the greatest attention should be paid to the eyes, which are particularly sensitive and susceptible, if hit by a laser beam for a sufficient time, even if of low power, they can suffer even irreparable damage.

We always recommend using laser-specific protective goggles and avoid any levity in handling laser modules.

Carefully consider also that lasers under environmental operating conditions other than those intended may emit laser radiation of a different type than the stated nominal type, for example, if operated in very cold environments some types of lasers may emit invisible infrared radiation, so on the surface they appear to be off or faulty while in fact they are emitting a treacherous and potentially dangerous invisible beam.

Therefore regardless of the module's CE certification, its class and the precautions taken according to prescriptions it is always important to maintain the highest level of care and caution when handling these instruments.

Laser classes

Below is the list of laser classes and a description of the risks, hazards and measures to be taken.

Summary List of Laser Classes

1. Class 1: low risk, harmless lasers under normal operating conditions
2. Class 1M: low risk, lasers that are harmless under normal operating conditions but may be hazardous when observed by means of optics (such as microscopes, eyepieces, binoculars etc.)
3. Class 1C: Low risk, these are lasers that operate only in contact with the tissue to be treated, are used for medical purposes, must comply with IEC 60601 or IEC 60335 standards
4. Class 2: Low risk, relatively harmless lasers, eyelid reaction within 250milliseconds is sufficient to avoid eye damage. The beam should not be directly observed or pointed directly at people
5. Class 2M: low risk, as for the previous class, eye damage is prevented by eyelid reaction, may be dangerous if observed by means of optics (such as microscopes, eyepieces, binoculars etc..), One should not observe the beam directly and should not point it directly at people
6. Class 3R: Medium risk, The beam should not be observed directly and should not be pointed directly at people. Only authorized and professionally trained persons through specific courses may be allowed to use it. TSL (Laser Safety Technician) technical support is required.
7. Class 3B: medium risk, are always dangerous if the beam is directly observed, the reflected beam is normally safe but it is not recommended to expose oneself to it, Use may be allowed only to authorized and professionally trained persons by means of specific courses. Access to the area where the laser is used must be barred to unauthorized persons. TSL (Laser Safety Technician) technical support is required.
8. Class 4: High risk, they are always dangerous if the beam is directly observed, the reflected beam is normally safe but definitely not recommended to be exposed to them. They are dangerous to the skin. Only authorized and professionally trained persons through specific courses may be allowed to use them. Access to the area where the laser is used must be barred to unauthorized persons. TSL (Laser Safety Technician) technical support is required.

Further extended alternative description of the various laser classes

Class 1

Under expected ordinary operating conditions they are safe. It is not necessary to establish a controlled area to use them. No key control is required to put them into operation. No professional training is required to use them; simply follow the manufacturer's instructions. Protective eyewear is not required. No special preventive measures are required for normal laser use.

Class 1M

Under ordinary expected operating conditions they are safe; they can be dangerous if optics are used. They must be used in a controlled area. No key control is required to operate them, No professional training is provided for use, but is recommended, just follow the manufacturer's instructions. Protective eyewear is not required. Collimation and focusing do not need to be changed..

Class 2

For the eyes, they are safe only for very brief exposures. It is not necessary to establish a controlled area to use them. No key control is required to put them into operation. There is no professional training for use; simply follow the manufacturer's instructions. Protective eyewear is not required. There is no need to stare at the laser beam.

Class 2M

For the eyes they are safe only for very brief exposures, can be dangerous if optics are used. They must be used in a controlled area. No key control is required to operate them, No professional training is provided for use, but is recommended, just follow the manufacturer's instructions. Protective eyewear is not required. One does not have to change the collimation and focus. One does not have to fix the laser beam.

Class 3R

They pose the risk of injury, increased if personnel are not trained. They must be used in a controlled area. No key control is required to operate them. It is required that personnel receive professional training. The use of protective eyewear is always recommended or required following risk assessment. Direct eye exposure should be avoided. The use of a laser radiation protection technician (GRT) is required.

Class 3B

Hazardous to eyes and skin, avoid direct exposure. Risk is increased if personnel are not trained. Must be used in a controlled area protected by interlock switch that disconnects power to the laser source. A key control is required to operate them. It is required that personnel receive professional training. The use of protective eyewear is required. Accidental direct and reflected eye and skin exposure must be avoided. The use of a laser radiation protection (GRT) technician is required.

Class 4

Hazardous to eyes and skin, avoid direct exposure. Can cause fires. Risk is increased if personnel are not trained. Must be used in a controlled area protected by interlock switch that disconnects power to the laser source. A key control is required to operate them. It is required that personnel receive professional training. The use of protective eyewear is required. Accidental direct and reflected eye and skin exposure must be avoided. The use of a laser radiation protection (GRT) technician is required.

Conclusions

Whenever you use a laser make sure you do so according to the instructions by following all requirements and taking every necessary minimum precaution provided as appropriate, also follow common sense and use reasonable caution beyond the minimum necessary directions.

Read the descriptions of the various classes well and learn more about the characteristics of the specific laser you need to use.

Also consider ce depending on one's use of the laser other risks are also possible, for example, the risk of chemical intoxication.

Also read the other articles we have published on the safe use of lasers.