Laser Helpers

A Suggested Inventory of Laser Safety Equipment

in Laser Safety

Many tools are available for analyzing and managing laser safety hazards. There is inconsistent terminology used in industry for describing some of these tools; we try here to point out a few of the more commonly used terms. The format follows the laser safety process: identify the hazards, analyze and measure the hazards, manage and/or mitigate the hazards.

 


Beam Locating Tools

Infrared Viewers

IR viewers allow for active viewing of the IR beam as it travels. IR viewers are very useful when there is a strong chance a beam is escaping a controlled area. Some models can be connected to (or are integrated with) cameras and other video output devices.

Ultraviolet Viewers

Similar to IR Viewers and cameras, but sensitive to the UV range.

Infrared Viewing Cards

IR viewing cards and discs convert infrared radiation to visible radiation. Some IR cards store energy from a conventional light source (e.g. indoor room lighting, sunlight) which is released in the form of visible light when stimulated by IR radiation. Other IR cards use photosensitive or “up conversion” materials.

Ultraviolet Viewing Cards

Similar to IR viewing cards and discs.

Burn Paper

Laser radiation-sensitive paper used to visually display a laser beam’s size, shape, or mode structure. An image of the beam is etched or burned onto the surface of the paper.


Beam Analysis Tools

Hazard Analysis Software

While never a substitute for an experienced Laser Safety Officer, look for software that has a simple user interface, stores calculations for future reference and generates both high-level management reports as well as more detailed reports documenting assumptions and results.

Power Meters

Your toolbox should include power meters suitable for your installation’s lasers which may range from handheld devices sensitive to nanowatts and nanojoules up to heavy duty detectors for kilowatt ranges.


Beam Containment Equipment

Laser Safety Curtains

Flexible or foldable laser absorbing materials are hung like curtains or drapes from track systems. These are often attached to, or suspended from, a ceiling, but may also be configured as floor-mounted systems with vertical uprights carrying the load. These may be referred to as “barriers” or “curtain barriers”.

Laser Safety Barriers

Laser barriers, also called partitions, guards or screens, are free-standing laser blocking devices. Many systems provide rollers or casters attached to the support legs. Some systems also provide a method or accessories for attaching multiple barriers together with no safety gaps.

Window Protection

Windows are covered with roll-up shades, sometimes called roller blinds and roller screens. Windows may also be covered by blocks which are laser safe materials incorporating hook-and-loop or other fastener systems and cut to fit directly over a window or port.

Bench Guards

Bench guards, also called bench blocks and beam stops, are small scale laser blocking devices for placement on, and attachment to, optical tables and similar laser installations. They normally take the form of metal panels attached directly to an optical table. Bench guards may be used to surround the entire perimeter of a table. They may also be used as “walls” when creating a temporary table top enclosure.

Beam Dumps

Beam dumps, also called beam traps and beam stops, collect directed laser radiation and convert the energy to heat. Some have “infinitely inward reflecting” designs that truly trap all the radiation. Both air-cooled and water-cooled models are available.

Laser Shutters

These devices are placed directly in the beam path to automatically or manually shut down the beam. Shutters often contain an integrated beam dump; other models will redirect the beam to a beam dump. Automatic shutters are normally tripped when an access door is opened or a similar non-safe event occurs.

Enclosures

A Class 1 Laser Enclosure is a device that fully surrounds a laser in such a way as to “reduce” the hazard from say, Class 4 to Class 1, thereby creating an eyesafe environment. These are usually sheet steel or aluminum in construction; they may incorporate doors, windows, and removable panels – all of which should be interlocked.


Entry-Way Controls

Interlocks

There is a wide selection of devices called generally “interlocks” which enable regulation or interruption of laser radiation when an “unsafe event” takes place. The simplest of these is a direct connection between a door or other entry and the power controls in the laser itself. Interlocks are often designed into curtains, barriers, rooms, and enclosures.

Safety Interlock System (SIS)

A network of safety controllers may be connected to the laser installation in what is called a Safety Interlock System. These systems can include control panels, keyed locks, emergency buttons, door locks, including magnetic door locks, buzzers, alarms, lighted signs, and keyless entry devices.

Signs & Labels

Warning, Notice, and Caution signs per ANSI Z136 are essential. Signs and labels are available in virtually any size and configuration and on substrates such as paper, vinyl, aluminum, and hard plastic.


Laser Filter Products (Absorbing and Reflecting)

Laser Protective Windows

Laser protective windows of acrylic, glass, polycarbonate, and other materials offer simultaneous workspace viewing and laser safety. Some manufacturers refer to these as “sheet” products. These technologies are typically absorptive.


Laser Protective Eyewear

These products may be referred to broadly as eyewear, glasses, or goggles. Laser protective eyewear may take several forms: dual-lens spectacles, single lens wraps/wraparounds, dual-lens goggles, single lens goggles, full face shields, plus a varied range of patient protection products. The laser safety lenses are typically glass or polycarbonate, they may be reflective and/or absorptive, and may utilize coatings or impregnated dyes or chemicals. Some eyewear products protect against just one wavelength; others protect against multiple wavelengths.


There are many products to choose from, each with a unique set of specifications, each with a unique set of applications. The laser user and the Laser Safety Officer should always seek experienced, qualified advice in selecting the right combinations of these tools.