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Design Criteria for Flexible Laser Safety Barriers... used in the industrial laser environment. Ryan F. Hemmerle Jay Parkinson R. James Rockwell, Jr. Rockwell Laser Industries. The most commonly asked questions. What is special about a “Laser Barrier”? When are laser barriers necessary ? - PowerPoint PPT Presentation
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Design Criteria for Flexible Design Criteria for Flexible Laser Safety Barriers...Laser Safety Barriers...used in the industrial laser environmentused in the industrial laser environment
Design Criteria for Flexible Design Criteria for Flexible Laser Safety Barriers...Laser Safety Barriers...used in the industrial laser environmentused in the industrial laser environment
Ryan F. HemmerleJay ParkinsonR. James Rockwell, Jr.Rockwell Laser Industries
The most commonly asked The most commonly asked questions...questions...
What is special about a “Laser Barrier”? When are laser barriers necessary? What options are available? What type of signs/labels are needed? Is the highest rating always needed? Can barriers be interlocked to the laser? What are the economics? (Is it cheaper to just
build walls?)
Lets Review ANSI..Lets Review ANSI....
“Where safety latches or interlocks are not feasible… One alternative is:
A door, blocking barrier, screen, curtains, etc. shall be used to block, screen or attenuate the laser radiation at the entryway.” ANSI Z136.1 4.3.10.2 (3)b
Total Hazard Evaluation...Total Hazard Evaluation...
“Such laser barriers shall be specifically selected to withstand direct and diffusely scattered beams. In this case, the barrier shall exhibit a damage threshold for beam penetration for a specific exposure time commensurate with the total hazard evaluation for the facility and specific application” ANSI Z136.1 Section 4.6.4
When are Laser Barriers When are Laser Barriers Necessary?Necessary?
To establish a permanent enclosure around a Class 3b or Class 4 Controlled area
Where conventional walls or windows would impede the manufacturing process
When the laser area may be frequently moved or repositioned to a new area
Efficiency and safety during times of maintenence and service…(Time is money)
Laser Protective Barriers for Laser Protective Barriers for Clean Room EnvironmentsClean Room Environments
Laser Protective Barriers Laser Protective Barriers Using Ceiling Mount DesignUsing Ceiling Mount Design
Laser Protective Barriers Laser Protective Barriers Using Floor Mount DesignUsing Floor Mount Design
Laser Protective Barriers Laser Protective Barriers With Interlocking FeaturesWith Interlocking Features
Objective: Objective: To Establish a Protocol For To Establish a Protocol For Choosing a Barrier Choosing a Barrier
Main items required... Laser parameters needed to determine barrier
threshold specifications Facility conditions during use:
Operation - Maintenance - Service The barrier mounting options:
Ceiling - Floor - Movable Frame The integration of entryway controls and
protective windows
Typical User RequirementsTypical User Requirements
Cost effective alternatives to permanent on-site construction
Compliance with ANSI Z136.1 and OSHA Design flexiblity for changing demands Temporary and/or permanent area safety
What Options are Available?What Options are Available?
Mounting Configuration Ceiling mounted track hardware Moveable floor frames
Clean Room computability Low particulate generation Anti-Static compatibility Washability
More Options...More Options...
Interlocks Infrared photo-trancevers wired to alarms hard-wired into laser system
Protective Window Films Wavelength dependant
Sinage and Labeling Compliance with ANSI and OSHA
Protective Barrier Labeling….Protective Barrier Labeling….
Proposed language for the “new” ANSI
Z136.1 Standard:
“ All laser protective barriers shall be labeled with the barrier threshold limit (BTL) and exposure time for which the limit applies and the beam exposure conditions under which protection is afforded.”
Proposed ANSI Z136.1 4.6.5.4
TYPICAL LASER BARRIER TYPICAL LASER BARRIER BTL TESTINGBTL TESTING
Laser barrier test showing various test spots Laser barrier test showing various test spots at different radiant exposure levelsat different radiant exposure levels
Laser Protective BarrierLaser Protective BarrierPenetration Threshold levels for four different barriersPenetration Threshold levels for four different barriers
Laser Beam Diameter (mm)Laser Beam Diameter (mm)
Irra
dia
nce
(W
cmIr
rad
ian
ce (
Wcm
22 ))
PTLPTL
300 W/cm300 W/cm22
200 W/cm200 W/cm22
100 W/cm100 W/cm22
PTL criteria setPTL criteria set
at a 5 mm beam at a 5 mm beam
diameterdiameter
2 W/cm2 W/cm22
Nd:YAG Laser @ 1064 nm & Argon Laser @ 514 nm for Nd:YAG Laser @ 1064 nm & Argon Laser @ 514 nm for 100 s.100 s.
Protective Barrier Labeling:Protective Barrier Labeling:A Suggested Format…A Suggested Format…
Barrier Model No. Exposure criteria Care and cleaning Laser exposure time,
BTL & Beam size specifications
Manufacturer ID
Other Typical User Other Typical User Requirements...Requirements...
Need for convenient barrier Storage “Complete” beam Containment Converting a Class 4 Controlled Area
into a Class 1 Area Maintenance and Service options Special Environments (ie: clean room,
medical, heavy industry…)
LPB CHECKLIST...LPB CHECKLIST... INSTALLATION ANALYSISINSTALLATION ANALYSIS
Application of laser:
Beam access possible in operation? Y/N Comments:
Beam access possible in maintenance? Y/N Comments:
CHECKLISTBARRIER MOUNTING INSTALLATION
Floor Frames: Gusset Strips: Ceiling Mount: Connection Strips Interlocking: Latch/Jamb:
Windows: Clean Room: Particulates: Anti-Static: Warning Signs:
Items to consider...
BTL GEOMETRIESBTL GEOMETRIES
FIBEROPTIC
LENS-ON-LASERINTRABEAM
Each case is defined by the application:
CHECKLISTLASER PARAMETER DATA:
LASER PARAMETERS
Laser type:______________________________________________Class: _______________________________________
Wavelength(s): ______________________________________ (m)Beam divergence: ________________________(mrad)
(see ill A # 1)
Beam diameter at exit of laser: __________________________(mm)
CHECKLISTLASER PARAMETER DATA:
OPERATION MODE
Pulsed ( ) Continuous Wave ( )
Pulse energy: __________________________________________(J)Maximum Average Power: __________________ (W)
Pulse length: _______________________________________ (sec.)
Repetition rate: _____________________________________(Hertz)
CHECKLISTLASER PARAMETER DATA:
DELIVERY OPTICS
Beam conduit ( ) Fiber optics ( )
Beam diameter just prior to lens: ________________________ (mm)Fiber optic numerical aperture:___________________
(see ill. B #3) (see ill. C # 5)
Focusing lens: focal length: ____________________________ (mm)Cone angle:___________________________(degrees) (see ill. C #6) (see ill. C #6)
CHECKLISTLASER PARAMETER DATA:
SYSTEM DESIGN & GEOMETRICAL FACTORS
Worse case viewing distance (diffuse targets): ___________________________ (in)
Nominal distance(s) from laser aperture to barrier: max: __________________ (feet) min: _____________________ (feet)
Choosing a Laser Protective Choosing a Laser Protective Barrier….Barrier….
1. Establish whether a conventional enclosure (walls or housing) is appropriate and will not impede the laser use
2. Establish whether a permanent or removable enclosure is required
3. Establish the features desired (dimensions, style, interlocking…etc.
Choosing a Laser Protective Choosing a Laser Protective Barrier….Barrier….
4. Evaluate the laser parameters and BTL
5. Determine the Installation requirements (ie: Floor Frames, Gusset Strips, Ceiling Mount, Connection Strips, Interlocking, Latch/Jamb…etc.)
6. Determine special requirements: (ie: Windows, Clean Room, Particulates, Anti-Static, Warning Signs…etc.)
SUMMARY….SUMMARY….
Laser barriers can provide special area protection that is MOVEABLE and/or PERMANENTand still provide area safety
Laser barriers are most often necessary when FLEXIBILITY and SPEED is needed for the laser installation
CEILING and FLOOR mounted units are available
SUMMARY….SUMMARY….
Laser protective barriers come in different BTL ratings for different user needs
Barriers can easily be interlocked to the laser Barriers are not inexpensive - but are usually
LESS expensive that building solid, permanent walls around the laser installation
Standard ansi-based signs/labels are recommended