Class 3 Vs Class 4 Laser

3b lasers are safer.

Class 3 vs class 4 laser.

Class iv laser companies use class 3b evidence to promote their products because they don t have much of their own. Class 3b lasers are also considered as biomodelators and class 4 as surgical lithic. In 2003 the fda approved the first class 4 laser greater than 0 5 watts for the relief of minor muscle and joint pain. The therapeutic vector dose of laser is the energy joules administered.

Dr lothar lilge on class 4 laser youtube. Maximum power output is separate from wavelength so you might find class iiib and class iv lasers with the same wavelength. The second method is used by lasersafetyfacts to determine nohd. Most laser products are required by law to have a label listing the class.

It will be listed either in arabic numerals 1 2 3r 3b 4 or in roman numerals i ii iiia iiib iv. Others offer pulsing to allow for heat dissipation. The effect of laser is achieved on the tissues that absorb the applied energy. Class 3b low power laser up to 500mw has the common name of cold laser and those of class 4 high energy hot laser.

The foundation of class iv laser therapy is based on the delivery of a therapeutic dose of joules to a large area of target tissue reducing variability in outcomes. There is zero published evidence to show that a class 4 laser penetrates deeper than a high powered 3b laser. If the class iv laser is in the 940 980nm wavelength range then it will penetrate less than a class 3b laser in the 800nm to 900 nm range. The pressure will also lead the laser probe closer to the target.

1 from 1 to 4 99 mw into a 7mm aperture e g pupil of the eye or 2 five times the class 2 limit of 2 5 mw cm2 which works out to be 12 5 mw cm2. The fda defines a class iiib laser as a device with a power output between 5 500mw 0 005 0 5w and a class iv laser as a device with a power output above 500mw 0 5w. Laser classes lasers are classified for safety purposes based on their potential for causing injury to humans eyes and skin. Thus a class 3b laser can penetrate deeper into tissue than a class iv laser and can therefore saturate the target faster.

3b laser systems cost less. Early fda approved therapy lasers were class 3b lasers maximum 0 5 watts. For example on a lower back a class iv therapy laser would treat at 10 joules cm 2 in a 10 minute treatment session of 10 watts in continuous wave 6 000 joules of energy would be. More absorption plus therapeutic effect.

One thing remains certain current scientific and clinical research proves that class 3b lasers are best suited for therapeutic applications and class 4 lasers are best suited for tissue destruction. A high energy laser can administer low doses.