Light, Sound & Radiation
Every light, sound & radiation calculator on CalcEngines — unit converters, derived indices and interpretive tools, each with its formula, a worked example and the reference intervals it is judged against.
5 calculators in this section
- Lux to PPFD Converter (by Light Source)Lux to PPFD and back for eleven named light sources, with the measured factor for each and where it was published — plus the daily light integral, crop DLI bands, and a plain refusal to give a single factor for a red/blue LED, with the arithmetic that shows why.
- Lux, Lumens and Candela ConverterLumens, candela, lux and foot-candles in every direction, through the solid angle and the distance that actually connect them — with the θ/2 in the cone formula spelt out, the luminance units (nit, foot-lambert, apostilb) carried too, and a plain statement of why nothing photometric converts to watts.
- Noise Exposure Dose Calculator (OSHA, NIOSH, EU)Occupational noise dose under all three regimes at once — OSHA's 5 dB exchange rate, NIOSH's 3 dB recommendation and the EU's L_EX,8h against its 80, 85 and 87 dB(A) values — with the formulas quoted from 29 CFR and the hearing-protector qualifier that everyone drops.
- Radiation Dose Converter (Gy, rad, Sv, rem, R)Gray, rad, sievert, rem, roentgen and C/kg — with the exact conversions separated from the two that are not conversions at all: gray to sievert needs a radiation weighting factor, and roentgen to gray needs an f-factor that depends on the material and the photon energy.
- Sound Pressure Level Converter (dB, Pa, W/m²)dB SPL to pascals to sound intensity and back, with the 20 µPa and 1 pW/m² references spelt out — including the 0.14 dB the two of them disagree by, because air is 413 rayl and the references assume 400.