S5.1.1.16 A lamp designed to use a
type of bulb that has not been assigned
a mean spherical candlepower rating
by its manufacturer and is not listed in
SAE Standard J573d, Lamp Bulbs and
Sealed Units, December 1968, shall meet
the applicable requirements of thisstandard when used with any bulb of
the type specified by the lamp manufacturer,
operated at the bulb’s design
voltage. A lamp that contains a sealed in
bulb shall meet these requirements
with the bulb operated at the bulb’s design
voltage.
S5.1.1.17 Except for a lamp having a
sealed-in bulb, a lamp shall meet the
applicable requirements of this standard
when tested with a bulb whose filament
is positioned within ±.010 inch of
the nominal design position specified
in SAE Standard J573d, Lamp Bulbs and
Sealed Units, December 1968, or specified
by the bulb manufacturer.
S5.1.1.6 Instead of the photometric
values specified in Table 1 of SAE
Standards J222 December 1970, or J585e
September 1977, a parking lamp or tail
lamp, respectively, shall meet the minimum
percentage specified in Figure 1a
of the corresponding minimum allowable
value specified in Figure 1b. The
maximum candlepower output of a
parking lamp shall not exceed that prescribed
in Figure 1b, or of a taillamp,
that prescribed in Figure 1b at H or
above. If the sum of the percentages of
the minimum candlepower measured at
the test points is not less than that
specified for each group listed in Figure
1c, a parking lamp or taillamp is
not required to meet the minimum
photometric value at each test point
specified in SAE Standards J222 or
J585e respectively
Source:
http://www.gpo.gov/fdsys/pkg/CFR-2010-title49-vol6/pdf/CFR-2010-title49-vol6-sec571-108Nt-.pdfhttps://law.resource.org/pub/us/cfr/ibr/005/sae.j222.1970.pdfhttp://archive.org/stream/gov.law.sae.j585.1977/sae.j585.1977_djvu.txtThese are old documents before LEDs were even a dream, but are still law, so if you are wanting to see a "LED bulbs are illegal inside of incandescent housings" in bold capital letters, you will be disappointed.
Perhaps some LED bulbs in some fixtures will meet the lighting requirements, when tested with proper photometric equipment. But an uninformed person with the ability to install a LED light bulb, simply cannot subjectively look at the light output and claim it meets the standards, and is safe and legal, and proclaim so.
While the lighting police will never be knocking at your door, one should at least be concerned whether their aftermarket lighting is not only not Glaringly bright to other drivers, but is visible from all angles required, and is of proper intensity to properly convey to other drivers what the driver is doing.
But unfortunately Humans have this need to justify their purchases and thump their chests.
If one insists on Putting LED bulbs into incandescent figures: the following was written by a moderator on the Candlepower forums, who knows more about this topic than anybody here.
A test lab is really the only way to get an accurate go/no-go test. If you are doing a purely visual evaluation, install one of the test bulbs (leave the stock bulb on the other side). Turn on the lamps with the truck out in bright daylight. Walk about 25 feet away from the truck and move in an arc (180°) from one side of the truck to the other, keeping both lamps in view to evaluate their relative visibility. Watch for how bright the lamps appear, the apparent size of the lit area, any "dropout" angles, any "flash" angles (extra bright light), shadows, etc. Then double your distance to the truck and walk back and forth again to compare the two sides. Once it's dark out, move the truck about 4 feet away from a wall or garage door, at 90° (not crooked), turn on the lamps, and look at the apparent brightness and size of the patch of light shining on the wall from the two lamps. A handheld light meter goes a long way here. If the light patch on the test bulb's side is dimmer and/or smaller, or there are dark streaks/shadows, or (in the daylight observation) if there are angles from which the test bulb is less visible than the filament bulb, the test bulb fails in that application. Of course, if you do see any shadows or bright spots or other artifacts, check to make sure the standard bulb doesn't have a comparable artifact on the other side. Also be sure to compare (day and night) the apparent bright/dim ratio. Often an LED retrofit will have insufficient difference between the bright (brake) and dim (tail) mode, which is very dangerous; it basically renders the lights useless for conveying the message they're supposed to convey.
None of this is sufficient to say for sure that the test bulb is good enough, but it's enough to reject the test bulb if it's bad enough.
Incandescent bulbs get dimmer with age. The lenses get hazed and cloudy with time and UV exposure. A brighter LED bulb is not the answer, and I am a bit sick of being blinded by superbright LED lights in people's brake lights, and those with HID retrofit bulbs in incandescent housings infuriate me and make me want to drive them off the road.
Thankfully they are starting to ticket those HID offenders, and hopefully the 'Blue is cool' mentality/fad dies out soon.
