Bandwidths of emission lines. Source Wavelength (nm) AES-1 AES-2 EPA NSF Hg 253.652 0.808 Hg 289.360 0.766 Hg 296.728 0.638 0.605 0.585 0.794 HeCd 325.029 0.601 0.550 HeCd 325.029 0.563 0.599 0.533 0.946 Hg 334.149 0.512 0.795 Hg 404.657 0.808 ÿ