Hand Pointer

Product Information

Examples of Class 3R laser products include some laser pointers and some alignment products used for home improvement work. 5.7 Class 3B Class 1M laser products are usually products that produce beams with a large diameter. Therefore, only a small part of the whole laser beam can enter the eye. As for a Class 1 laser product, they are safe for the naked eye under reasonably foreseeable conditions of operation. However, these laser products can be harmful to the eye if the beam is viewed using magnifying optical instruments. Lasers produce radiation with unique properties. It is these properties that distinguish laser radiation from the optical radiation produced by more familiar sources such as the sun or the common household electric light bulb.

The classification scheme for lasers indicates the potential risk of adverse health effects, where the higher the class number, the greater the laser radiation hazard posed by the laser. In practice, the risk also depends upon the conditions of use, exposure time and the environment. However, potential risks may or may not actually lead to adverse health effects, so with the help of classification, users may select appropriate control measures to minimise the risks. Class 3R laser products are higher powered devices than Class 1 and Class 2 and may have a maximum output power of 5 mW or 5 times the AEL for a Class 1 laser product. The laser beams from these products exceed the MPE for accidental viewing and can potentially cause eye injuries, but practically the risk of injury in most cases is relatively low for short and unintentional exposure. The risk is limited because of natural aversion behaviour for exposure to bright light for the case of visible radiation and by the response to heating of the cornea for far infrared radiation. A laser is assigned to a particular class when the measured emission level exceeds the AEL for all lower laser classes but does not exceed the AEL for the class assigned. For example, a laser will be assigned as a Class 3R laser product when the maximum measured accessible emission level exceeds Class 1, Class 1M, Class 2 and Class 2M AEL values but does not exceed the Class 3R AEL. The response of the human eye is wavelength dependent and peaks at around 555 nm, the response decreasing as either end of the visible spectrum is approached (400 nm to 780 nm). As a result, if laser pointers are compared at 3 different wavelengths (670 nm, 635 nm and 532 nm) but at the same radiant power, the brightness as perceived by the eye will be approximately in the ratios 1 : 10 : 30.At home, lasers can be found in many modern appliances such as in computers, laser printers, DVD and Blu-Ray® players. In these appliances the consumer would have no access to the laser in normal use. If the laser emits in the visible region then the radiation is perceived as a single colour. The wavelength of light is usually measured in nanometres, or one-thousand-millionth of a metre and is abbreviated to ‘ nm’. Class 2M laser products are products which produce beams with a large diameter beam in the wavelength range 400 to 700 nm. Therefore, only a small part of the whole laser beam can enter the eye and this is limited to 1 mW, similar to a Class 2 laser product. However, these products can be harmful to the eye if the beam is viewed using magnifying optical instruments. 5.6 Class 3R If product mislabelling is suspected, or there is doubt over the classification of a product then measurements should be carried out in accordance with the requirements of the British Standard to determine the actual laser class to which the device should be assigned. There is no simple test available to the general public to determine the radiant power of a laser product. A visual inspection of the laser product or its laser output will not provide any indication of the appropriate class for the device. PHE advises that the sale of laser products to the general public for use as laser pointers should be restricted to Class 1 or Class 2 devices which should be classified in accordance with the requirements of the current British Standard and should be sold with sufficient accompanying information to enable the user to operate the product in a safe manner. Toys should be Class 1 or of such low output that they do not need to be classified.

PHE provides advice to the Department for Business, Energy and Industrial Strategy ( BEIS) and Trading Standards concerning the safety of hand-held laser pointers and the optical hazards posed by the use of these products. 2. Laser radiation

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When considering the safety implications of the laser beam an important parameter is the power (in Watts) or energy (in Joules) in the beam divided by the cross-sectional area (in m 2) of the beam. This is called the irradiance and is usually quoted in watts per square metre or W m -2 or radiant exposure usually quoted in J m -2. 3. Laser pointers or laser pens

The optical radiation produced for lighting is said to be highly divergent, that is the light spreads out rapidly as the observer moves away from the bulb. It is this property which allows the illumination of large areas using a single light bulb. In contrast a laser produces optical radiation over a very narrow wavelength band, so narrow that the laser is referred to as a monochromatic or single wavelength source. The advice from PHE takes account of the current British Standard for laser safety, and the technically equivalent European and International Standards.The British Standard provides advice on the use of lasers for demonstrations, displays and exhibition and states that only Class 1 or Class 2 devices should be used in unsupervised areas unless under the control of experienced well-trained operators. Class 4 laser products have an output power greater than 500 mW (half a watt). There is no upper restriction on output power. Class 4 laser products are capable of causing injury to both the eye and skin from direct exposure and reflections also may be hazardous. Class 4 laser beams also present a fire hazard. Lasers used for many laser displays, laser surgery and cutting metals may be Class 4 products.