Laser Safety Protocols and Interpretations
Section 18.104.22.168 of Pub 3000, Laser Chapter states “ At LBNL, the LSO shall develop and issue laser protocols, which are interpretations of ANSI Z136.1 requirements that provide acceptable solutions for frequently encountered experimental situations, or resolve conflicts between standards, where the primary Z136.1 recommended control measures are not feasible or practical. Such protocols will be reviewed and approved by the LBNL Laser Safety Committee to ensure they provide equivalent protection, and fit into LBNL’s research environment and needs. Prior to implementing these protocols, they shall go to the U.S. Department of Energy (DOE) Berkeley Site Office (BSO) for review. As appropriate, they will be forwarded to the LBNL Safety Review Committee (SRC) for institutional review and approval.”
Below are links to individual Laser protocols.
Protocol #1 Applicability of Control Measures
Documentation of the LBNL standard protocol for Applicability of Control Measures, in such cases where more than one control measure accomplishes the same purpose the LSO shall select the most appropriate control(s) and document in the specific AHD.
Protocol #2 Laser Room Access Interlock Protocol
To ensure that laser-room access systems (interlocks) are functioning properly. This will require a testing of the functionality of the interlock system—illuminated sign, shutters, power-supply connection, bypass switch, etc.—on a six-month frequency, with proper documentation.
The user can declare a period of non-laser operation to avoid periodic requirements from becoming past due as a result of non-operation. Prior to start up, the interlock check shall be performed, and LSO notified. One interlock check can be performed as part of annual AHD renewal. Documentation can be on a user-generated form, a log-style record, or an EH&S-suggested form.
Protocol # 3 Key Control
The Laser Safety Officer at LBNL will not require the installation of a master-switch/key control mechanism on non–Center for Devices and Radiological Health (CDRH)–certified lasers or laser systems, or the removal of said key during periods of disuse. This includes circumstances where the users are the developers/builders of laser systems.
Protocol #4: Activation/audible/ visual laser warning signs at LBNL.
The Laser Safety Officer at LBNL will evaluate on an individual basis the necessity for activation/audible/visual warning devices/signs for all Class-3B and Class-4 laser use areas. The requirement for activation warning systems will be made based on this evaluation.
Protocol # 5: ANSI Z136.1 Style Warning Signs
The Laser Safety Program at LBNL has determined that not all the information required in ANSI Z136.1, Section 22.214.171.124, is of value in our setting, and will modify our warning signs in the following manner:
Below the tail of the sunburst, present/accessible wavelengths and required optical density will be the preferred information on display. In some cases where four or greater wavelengths are in use, the warning sign will simply state, “Multiple wavelengths are in use. Check with operator for proper protective eyewear.”
Protocol #6: ANSI Z136.1 Remote connector
The Laser Safety Program will encourage, but not require, the installation of a remote interlock connector on laser systems (power supplies). The ANSI standard only calls for its availability; it does not mandate its use. For the reduction of laser output as part of an access interlock, the use of external shutters is an equivalent approach to dropping power to the laser power supply.
Protocol #7 Emergency Stop
When applicable or requested by the user, a laser emergency “crash” button (panic button or E-stop) will be installed as part of an interlocked laser-room access system.
In some cases, the indication of the location of electrical circuit breakers or laser cutoff switches will be sufficient to act as a replacement for this device.
An evaluation by the LSO may determine that the panic button is not required.
Protocol #8: ANSI Z136.1 Use of Alignment Eyewear
The Laser Safety Program at LBNL has determined that on a case by case basis the use of Alignment Laser Protective Eyewear will be authorized. This eyewear is to allow greater visibility of visible beams during alignment activities. Rather than having the user lift up full protection eyewear to see the beam location.
Protocol #9: ANSI Z136.1 Nominal Hazard Zone Boundary
The Laser Safety Program at LBNL has determined that not all the information required in ANSI Z136.1-2000, Section 126.96.36.199, is of value in our setting, Recognizing the nature of research, the majority of times the laser use room will be posted with appropriate laser warning signs rather than the exact demarcation line of safe and unsafe (NHZ). This protocol is in compliance with ANSI Z136.1-2007
Protocol #10: ANSI Z136.1 Standard Operating Procedures (Activity Hazard Document)
All LBNL SOPs (AHDs) are written by the user and approved by the LSO and their home division management. The official version will be maintained on line. Users have the option to print off a copy for internal lab use, but are not required to do so or keep with their laser systems.
Protocol #11: ANSI Z136.1 Beam Stop or Attenuator Class 4
LBNL laser safety beam containment controls provide equivalent safety to that provided by a permanently attached beam stop or attenuator for its class 4 lasers.
Protocol #12: ANSI Z136.1 Interlocks on Removable Protective Housings
Interlocks on removable Protective Housings covering the laser mechanism (resonance cavity) for certified laser products will be interlocked. Those covering non-certified units or enclosing the optical set up are not required to be interlocked as per section 188.8.131.52. (2000 version) and table enclosures are considered barriers per the ANSI Z136.1 2007 version. A non interlocked protective housing label or sign will be an added awareness item when feasible.
Protocol #13: ANSI Z136.1 Labeling of Laser Protective Windows and Barriers
The Laser Safety Program at LBNL will attempt to label laser protective barriers and windows (in particular those that unauthorized staff may come in contact with). The protective level of un-labeled windows and barriers will be addressed within specific AHDs. Barriers that are used for cleanliness only and do not provide laser beam protection will be labeled to indicate that.
Protocol #14 ANSI Z136.1 Hazard Calculations
The Laser Safety Program at LBNL will evaluate each new addition of ANSI Z136.1 Safe Use of Laser for changes in MPE values. Upon completion of this review, the LSO will update laser hazard calculations table per AHD as applicable.