{"id":61824,"date":"2026-04-13T15:59:51","date_gmt":"2026-04-13T15:59:51","guid":{"rendered":"https:\/\/stagingphotonics.laser2000.co.uk\/?p=61824"},"modified":"2026-05-14T09:08:45","modified_gmt":"2026-05-14T09:08:45","slug":"standards-for-laser-safety-eyewear-en207-en208","status":"publish","type":"post","link":"https:\/\/stagingphotonics.laser2000.co.uk\/?p=61824","title":{"rendered":"Laser Safety Standards Guide: Decoding EN 207 & EN 208"},"content":{"rendered":"\t\t
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The Ultimate Guide to Laser Safety Eyewear Standards: EN 207, EN 208, and ANSI Explained<\/h1>

Choosing the correct laser safety eyewear is a critical responsibility for any Laser Safety Officer (LSO) or facility manager. Whether you operate in a medical, industrial, or research environment, understanding the nuances of global laser safety standards\u2014specifically EN 207<\/b>, EN 208<\/b>, and ANSI Z136<\/b>\u2014is essential for compliance and, most importantly, preventing irreversible eye injury.<\/p>

If you are looking for a comprehensive breakdown on navigating these standards while shopping for the right frames and filters, we highly recommend reading The Ultimate Buyer\u2019s Guide: How to Choose Laser Safety Glasses – Laser 2000<\/a>.This guide breaks down\u00a0everything you need to know about optical density, damage thresholds, CE marking, and how to properly select and maintain your Personal Protective Equipment (PPE).<\/span><\/p>

\"High-quality<\/h1>

\u00a0<\/h2>

The Danger of Relying Solely on Optical Density (OD)<\/h2>

Historically, and still predominantly under the American ANSI Z136<\/b> standard, laser safety goggles are specified by their Optical Density (OD)<\/b>. OD is the logarithmic measurement of how much a filter attenuates (blocks) light at a specific wavelength.<\/p>

For example, an OD of 6 at 1064 nm means the eyewear reduces the transmitted light by a factor of 1,000,000.<\/p>

The Fatal Flaw of OD<\/h3>

Specifying eyewear by Optical Density alone completely ignores the material’s damage threshold<\/b>\u2014the maximum power or energy density the eyewear can physically withstand before melting, shattering, or burning.<\/p>

Imagine a high-power CO2 laser emitting at 10,600 nm. If you use polycarbonate safety glasses with an OD > 6, you might assume you are protected against a 10 kW beam. However, if that polycarbonate filter is subjected to a direct hit from even a 20 W beam, the material will burn through in seconds, rendering the Optical Density completely useless and exposing the eye to severe danger.<\/p>

Decoding EN 207: The European Standard for Laser Safety<\/h2>

To solve the damage threshold problem, the European Union introduced EN 207<\/b>. Since becoming a harmonized standard in 1997, any laser eye protection sold in the EU or UK must be certified to this standard (or EN 208 for alignment).<\/p>

Under EN 207, laser safety eyewear is subjected to rigorous direct hit testing<\/b> by an independent, government-approved notified body. Self-certification is strictly illegal.<\/p>

To pass, the filter and frame must withstand a direct laser hit for at least 5 seconds (continuous wave)<\/b> or 50 pulses (pulsed mode)<\/b> without exceeding the\u00a0critical safety limits (Class 1)<\/a>\u00a0on the eye side of the lens.<\/p>

\"Laser<\/p>

Understanding EN 207 Markings (LB Ratings)<\/h3>

When you purchase EN 207 certified glasses, they will feature specific markings indicating their LB Rating<\/b> (formerly L-Rating prior to 2010). This rating combines both the required Optical Density and the tested damage threshold.<\/p>

A typical marking looks like this: 315 \u2013 1400 D LB5 I LB5 R LB6 M LB4<\/b><\/p>

Here is how to decode the operating modes:<\/p>

Marking<\/th>Laser Operating Mode<\/th>Pulse Length<\/th>Common Applications<\/th><\/tr><\/thead>
D<\/strong><\/td>Continuous Wave (CW)<\/td>N\/A<\/td>Cutting, welding, medical lasers<\/td><\/tr>
I<\/strong><\/td>Long Pulse<\/td>1 \u00b5s to 250 ms<\/td>Hair removal, aesthetics<\/td><\/tr>
R<\/strong><\/td>Q-Switched<\/td>1 ns to 1 \u00b5s<\/td>Tattoo removal, LIDAR<\/td><\/tr>
M<\/strong><\/td>Femtosecond \/ Picosecond<\/td>< 1 ns<\/td>Microscopy, precise material ablation<\/td><\/tr><\/tbody><\/table><\/div>

The LB Number<\/b> (e.g., LB5, LB6) dictates the maximum power or energy density the eyewear can withstand. An increase of 1 in the LB number equates to a tenfold increase in protection (one order of magnitude).<\/p>

EN 207 Protection Levels (LB Ratings)<\/h3>

Use the table below to determine the required protection level based on the laser’s power or energy density.<\/p>

Scale Number<\/th>Max Transmission<\/th>D (W\/m\u00b2) CW<\/th>I, R (J\/m\u00b2) Pulsed<\/th>M (W\/m\u00b2) Femto<\/th><\/tr><\/thead>
LB1<\/strong><\/td>10%<\/td>100<\/td>0.05<\/td>0.0015<\/td><\/tr>
LB3<\/strong><\/td>0.1%<\/td>10,000<\/td>5<\/td>0.15<\/td><\/tr>
LB5<\/strong><\/td>0.001%<\/td>1,000,000<\/td>500<\/td>15<\/td><\/tr>
LB7<\/strong><\/td>0.00001%<\/td>100,000,000<\/td>50,000<\/td>1,500<\/td><\/tr><\/tbody><\/table><\/div>

EN 208: Laser Alignment Eyewear<\/h2>

While EN 207 is for complete protection, EN 208<\/b> dictates the standards for laser alignment glasses. These are designed exclusively for adjusting visible-beam lasers (400 nm to 700 nm).<\/p>

Instead of completely blocking the beam, EN 208 glasses attenuate the incident power down to a safe Class 2 level (< 1 mW). This allows the technician to safely see the beam spot for alignment purposes. Like EN 207, they are rated by damage thresholds (labeled as RB levels<\/b>) and must survive the 5-second \/ 50-pulse direct hit test.<\/p>

EN 208: Laser Alignment Eyewear<\/h2>

EN 208<\/b> dictates the standards for laser alignment glasses (visible beams 400nm \u2013 700nm). These reduce power to a safe Class 2 level (< 1mW) so you can still see the beam spot for adjustment.<\/p>

\"EN<\/p>

EN 208 Alignment Levels (RB Ratings)<\/h3>
Scale Number<\/th>Max Power (W)<\/th>Max Pulse Energy (J)<\/th>Spectral Transmission<\/th><\/tr><\/thead>
RB1<\/strong><\/td>0.01<\/td>0.000002<\/td>0.01 to 0.1<\/td><\/tr>
RB2<\/strong><\/td>0.1<\/td>0.00002<\/td>0.001 to 0.01<\/td><\/tr>
RB3<\/strong><\/td>1<\/td>0.0002<\/td>0.0001 to 0.001<\/td><\/tr>
RB4<\/strong><\/td>10<\/td>0.002<\/td>0.00001 to 0.0001<\/td><\/tr>
RB5<\/strong><\/td>100<\/td>0.02<\/td>0.000001 to 0.00001<\/td><\/tr><\/tbody><\/table><\/div>

EN 207 vs. ANSI Z136: A Global Comparison<\/h2>

Depending on your region, you will follow different legal frameworks. Here is a quick comparison of the European and American approaches:<\/p>

Feature<\/th>EN 207 (Europe \/ UK)<\/th>ANSI Z136 (USA)<\/th><\/tr><\/thead>
Primary Metric<\/strong><\/td>LB Rating (Damage Threshold + OD)<\/td>Optical Density (OD) alone<\/td><\/tr>
Direct Hit Testing<\/strong><\/td>Mandatory (5 seconds or 50 pulses)<\/td>Not required by the standard<\/td><\/tr>
Certification<\/strong><\/td>Independent Notified Body required<\/td>Self-certification allowed<\/td><\/tr>
Focus<\/strong><\/td>Guaranteed structural integrity<\/td>Attenuation of light within the NHZ<\/td><\/tr><\/tbody><\/table><\/div><\/div>

Note on the Nominal Hazard Zone (NHZ):<\/i> ANSI allows a Laser Safety Officer to define an NHZ. Outside this zone, standard OD-rated eyewear is considered adequate against stray light, whereas EN 207 requires worst-case scenario testing regardless of zone.<\/p>

Legal Compliance: CE Marking and UKCA<\/h2>

Under Personal Protective Equipment (PPE) Regulations, it is illegal to sell non-certified laser safety glasses in Europe.<\/p>