# Presentation: 047923

## Laser Safety Barriers:

**Control Measures of the 3rd Kind**

- Prepared for:
- 4th Annual Laser Safety Officer
- Advanced Training Workshop
- July 15-17, 2008

## How does ANSI Z136.1 define Laser Barriers?

- LASER BARRIER: "A device used to block or attenuate incident direct or diffuse laser radiation.”  (ANSI Z136.1)
- Laser Barriers are a PHYSICAL CONTROL MEASURE
- Free standing screens, typically on wheels
- Track mounted curtains or barriers with track & rollers
- Floor-mounted, immovable screens
- Other similar
- Laser Barriers are considered as a LAST RESORT

**Notes:**
	*ANSI Z136.1-2007 defines a LASER BARRIER as: "A device used to block or attenuate incident direct or diffuse laser radiation.”
	*ANSI Z136.1-2007 goes on to establish their efficacy in a condition(s) where: "Laser barriers are frequently used during times of service to the laser system when it is desirable to establish a boundary for a controlled laser area."

## How does ANSI prioritize Laser Barriers in the control measures hierarchy?

- Laser Safety
- Risk

- Engineering Controls

- Administrative & Procedural

- Physical Controls

- Exposed Beam
- Potential for Exposed Beam

- Enclosures
- Interlocks

- Signage
- Work Procedures

- Screens
- Curtains

**Notes:**
Add more details about controls....

## How not to proceed.... 

- Laser Safety
- Risk

- Engineering Controls

- Administrative & Procedural

- Physical Controls

- Barriers
- Curtains

**Notes:**
Add more details about controls....

## How does the LSO confirm the use of Laser Barriers as a control measure?

- Door latches or room interlocks are not feasible.

**Permanent or Fixed Conditions**

**Temporary Conditions**

- No protective housing _and_ when AELs exceed safe limits.

- Entry into NHZ is required (during routine service or maintenance, for example)

- Protective housing is removed or interlocks are defeated _and_ when accessible laser radiation exceed MPEs.

**Safeguard an Entryway**
**(Section 4.3.10.2.2)**

**Surround the Laser**
**(Section 4.3.1.1)**

**Notes:**
ANSI Z136.1-2007 (Section 4 ~ Control Measures) goes on to indicate that laser barriers should/shall be used:

	*At an entryway where safety latches or interlocks are not feasible or are inappropriate to the (Class 4) laser operation in question (Section 4.3.10.2.2).

	*When operating a laser (Class 3B or 4) without a protective housing and where AELs exceed safe operation (Section 4.3.11).

	*To create a Temporary Laser Controlled Area (All Laser Classes) where entry into the NHZ becomes necessary (such as for routine laser service or maintenance), or when protective housings are removed or interlocks are defeated and the accessible laser radiation exceeds the applicable MPE (Section 4.3.12).

## How does the LSO choose a Laser Barrier configuration?

- Identify area needing to be enclosed.
- Confirm Engineering, Procedural, and Administrative Control options have been exhausted.
- Calculate power density for point source intrabeam and point source diffused laser outputs at closest distance to barrier.
- Select a value reflecting “operational reality” and use that to determine which laser barrier provides adequate protection.
- Evaluate desire to temporarily remove barrier vs. need to establish permanent barrier.

**Notes:**
When it is apparent that a laser barrier is the most effective control measure by which to ensure safe laser operation or maintenance, what are the most salient considerations that determine what type of barrier would be of greatest benefit?

	*Identify the entire area within which laser barriers would need to be erected.

	*Calculate the power density for both point source intrabeam and point source diffused laser outputs at the closest distance at which these same power density values could impinge upon the laser barriers.

	*Decide which power density value is actually an “operational reality” and use that same power density as the measure to evaluate which laser barrier possesses sufficient attenuation.

	*Evaluate the desire to temporarily remove the barrier vs. the need to establish a permanent laser barrier fixture which then becomes an immutable feature of the laser room.

## Finally, what else should be considered in defining a Laser Barrier system?

- Clean room compatibility
- CE certification
- Floor mounted, ceiling mounted, free-standing or removable designs
- Simple “light blocking non-laser protection” vs. laser attenuating barriers
- A free-standing “laser pod” design
- Barrier interlocks
- Illuminated signage
- Need for access and frequency of access
- Need for “valances” at ceiling or “skirts” at the floor
- Hardware requirements
- Ease of installation

**Notes:**
Finally, evaluate the need for unique laser barrier designs and/or ancillary laser barrier features, such as:
	Clean room compatibility
	CE certification
	Floor mounted, ceiling mounted, free-standing or removable barrier designs
	Simple “light-blocking non-laser protection” vs. laser attenuative barriers
	A free-standing “laser barrier pod” design
	Barrier interlocks
	Entry guard illuminated signage
	Barriers which “accordian” together to minimize its foot print and allow ready access
	Optical table only laser barriers
	Potential skin irritants (i.e., fiberglass for fire retardant properties)
	Laser blocking and/or light blocking valence extensions to both floor and/or ceiling
	Hardware requirements and perceived ease/difficulty of installation

## Who can you contact?  What do they offer?

- We will distribute marketing materials from these manufacturers indicating the laser barrier and containment products they offer:
- Kentek Corporation
- LaserVision
- Rockwell Laser Industries
- Wilson Industries

**Notes:**
Now that you have all technical requirements and physical dimension attributes assigned, who can you contact and what do they offer?

	*The primary manufacturers of laser protective barriers are: Kentek Corporation, LaserVision, Rockwell Laser Industries and Wilson Industries

	*We will distribute to you marketing materials from all of these manufacturers indicating the laser barrier and containment products they offer

## Questions?

**Notes:**
	*In closing, do you have any questions for me?