- What should I know before using/buying a laser pointer?
- Should I buy laser pointers over the Internet?
- How do I apply for licences to own and use a controlled laser?
Laser pointers are hand-held, pen-like and battery-powered devices that can project a laser beam for the purpose of highlighting key locations at a distance or areas of interest on the screens during presentations. Commonly available laser pointers emit red-coloured light although more expensive pointers which emit green or blue light exist too. Red light laser pointers usually come under the laser classes of 1, 2 or 3A, with beam power up to 5 milliwatts (mW). These classes give users an indication of the degree of laser hazard. The higher the class, the more powerful the laser and the greater will be its potential to pose serious danger if used improperly. More powerful classes of laser pointers exist – these are the Class 3b and Class 4 laser pointers (see FAQ below for further information). The laser beams from these pointers may reach a few hundred milliwatts (mW), and they are extremely dangerous. Licences are required to import, to possess and to use such lasers and the licence fees can be many times of the cost of the laser pointers.
Even at a very low power of 5 mW, when the laser is aimed directly at the eye, it will cause temporary flash blindness. A split second brief exposure from such lasers is not likely to cause permanent injury immediately because the eye will blink and move to avoid the beam, but it can lead to visual loss in later years. Hence it is not safe to use Class 3b or Class 4 laser pointers that have powers in excess of 5 mW.
In Singapore, the legislations for lasers come under the Radiation Protection Act (Chap 262) and its Regulations, which are administered by the National Environment Agency (NEA). Under the legislations, all Class 3b and Class 4 laser apparatus, including laser pointers belonging to these classes, are controlled apparatus. The owners (or the person in possession) and the operators of these controlled apparatus are required to have the necessary licences in order to legally possess and/or use the apparatus. (Please refer to the regulatory notes/documents for a more detailed description on the types of controlled lasers.)
The following are guidelines one should observe when operating a laser, and are useful for people handling laser pointers:
- Do not operate a laser if the hazard class of the laser is not shown on the warning label for the laser.
- Never aim or shine a laser beam at yourself, at anyone or at an aircraft or a moving vehicle.
- Laser radiation should be discharged in a background that is non-reflective and fire resistant.
- The target area where a laser beam shines on should be cleared of personnel for a reasonable distance.
- Warning signs should be attached to laser equipment in a conspicuous location indicating the potential eye hazard associated with laser.
- Avoid aiming laser with eye or looking along the axis of the beam.
- Looking into a primary laser beam should be avoided at all times, and equal care should be exerted to avoid looking at specula reflections of the beam, including those from lens/glass surfaces.
- Laser work should be carried in areas of high general illuminations to keep pupils constricted; this will limit the laser energy which might inadvertently enter the eyes.
- Laser radiation workers should be instructed on potential eye hazards and the importance of limiting unnecessary exposure.
- Wherever possible, safety eyewear designed to filter out specific frequencies characteristic of a laser system should be worn, but it should be noted that this form of protection may only be partial.
- Binoculars or aiming telescopes should not be used to view direct beam or reflected beam from mirrors unless the beam intensities are greatly below the safe levels. If necessary, a filter having sufficient optical density should be placed in the optical path of the binoculars or telescopes for such situations or adequate laser protective eye wear be worn by the operator.
In the event of injury, immediately consult your eye doctor. You should also notify the National Environment Agency immediately.