Calculate sound level in decibels: dB = 10 × log₁₀(I / I₀). Reference I₀ = 10⁻¹² W/m² (threshold of hearing).
Use scientific notation, e.g. 1e-6
dB = 10 × log₁₀(1.00e-6 / 10⁻¹²) = 60.00 dB