[Don]

An excellent question!

1. All meter readings 5.0, 6.0 and 7.0 are identical.

First of all, let's look at the 7.0 (MED/hour) readings. If they were identical, i.e., the Te (4.0 MED) times were the same, they would have equal erythemal (sunburning) power. A 12 minute Te time is the same no matter the irradiance source.

Next, even if the 5.0 and 6.0 readings were the same, you won't know if there are important differences in the spectral distribution. For that, you need a spectroradiometer so that you can measure the irradiance at 1.0 nm increments. Every salon should have a set of hand-held radiometers for quality control purposes but they are not recommended for comparing one sunlamp to another sunlamp and especially not for comparing one irradiance source to another irradiance source.


2. If you had 1 high pressure bed and one 160 new era lamped bed and they both metered the same, would the tanning results be the same or not?

While new-era sunlamps have "narrowed the gap" between low pressure and HID/hp tanning (a 160w new-era lamp is about equal to a 600w-700w HID/hp lamp for tanning power), a 160w LP lamp doesn't have the tanning power of a 1000w/1400w HID/hp lamp.

Therefore, even though the meters may read the same, the HID/hp sunbed (assuming it has 1000w/1400w sunlamps) will have more tanning power than a 160w new-era LP sunlamp equipped sunbed.

For those "techies" out there who are curious why this is true, it is because the 1000w/1400w HID/hp sunlamps have more photons in the 400 nm - 430 nm wavelength area than does any LP sunlamp (traditional or new-era) and we now know that although these wavelengths don't have enough erythemal power to cause sunburning, they have enough power to tan.

There is, however, a good way to prove to yourself that the HID/hp sunbed has more tanning power than the 160w sunbed equipped with new-era sunlamps, even if you don't have a spectroradiometer.

Tan in both of them yourself.