I'm a researcher at University Federal of Santa Catarina Brazil and I work with lasers.
I'm looking for information about how to calculate the Nominal Ocular Hazard Distance (NOHD) to a laser line and not to a laser point.
I have a laser line with 150 mW, thickness 1,14 mm with working distance 5m and fan angle 30°. Link
I would like to know the Nominal Ocular Hazard Distance (NOHD) with application to this laser line.
Assuming this is a CW laser operating between 400nm-700nm:
$E$ (our irradiance) is taken to be the MPE (maximum permissible exposure) of a Class 2 laser: $1.8T^{-0.25} \times 10^{-3} \text{ watts/cm}^2$
Our NOHD will be:
$$D_{\text{NOHD}}=\frac{\phi}{w\times\theta\frac{\pi}{180}\times1.8T^{-0.25} \times 10^{-3} \text{ W/cm}^2}$$
where $w$ is our beam width (should be 7mm for lasers with a beam width less than 0.7mm), $\theta$ is our fan angle, and $\phi$ is our radiant power.
Plugging in our values and making $T$ a 'blink': $$D_{\text{NOHD}}=\frac{150\times10^{-3}\text{ W}}{0.7\text{ cm}\times 30^{\circ} \frac{\pi}{180}\times1.8\times0.25^{-0.25} \times 10^{-3} \text{ W/cm}^2}=160\text{ cm}$$
You have posted too little information really. What kind of laser is it? Wavelength? CW? Pulsed? Class?
