Daytime Running Lights changed ???

[Wisha Haddan H3]

Originally Posted by Michael1

Does anyone read anything here? GM's study showed DRLs improving the accident rate at NIGHT! How does a DAYTIME Running Lamp improve your accident rate at night? What more proof do you need to know the study is flawed?

This does not discredit the study. There is good reason to include nighttime crash statics in an analysis of DRLs. For example:

1. Many DRLs are controlled by a light sensor, which automatically turns on full wattage and activates marker lights during dusk/dawn/night. With nothing to forget, the driver's risk could decrease.
2. Drivers with DRLs that aren't controlled by a light sensor may forget to turn them on. This leaves their car with headlights at half power and no tail/marker lights during dusk/dawn/night hours. The driver's risk could rise.
3. Headlamps burn out more quickly with DRL than without. If a lamp burns out at dusk/dawn/night, the driver's risk could rise.
4. Including nighttime statistics also eliminates the variables of winter/summer daylight hours and the need to define "dusk" and "dawn".

Most of these variables were called out in the study ... didn't you read it?

[Michael1]

Originally Posted by Wisha Haddan H3

This does not discredit the study. There is good reason to include nighttime crash statics in an analysis of DRLs. For example:

1. Many DRLs are controlled by a light sensor, which automatically turns on full wattage and activates marker lights during dusk/dawn/night. With nothing to forget, the driver's risk could decrease.

What percentage of cars do you see driving around at night with no lights on? It is not zero, but it is pretty close to it.

4. Including nighttime statistics also eliminates the variables of winter/summer daylight hours and the need to define "dusk" and "dawn".

It doesn't eliminate variables. It ADDS a control variable. The statistics shouldn't change one bit with or without DRLs at night. If it does, you know there is noise in the data, and you use that to build a confidence band.

Michael

[dеiтайожни]

Originally Posted by Michael1

30 million vehicles on road during day x 2 DRL lamps x 20 watts each (half power headlamps) = 1200 megawatts.

1,200,000,000 watts x 10 hours of daylight / 0.6 alternator efficiency / 0.2 engine efficiency / 1000 watts/kW/ 32.6 kW-hr per gallon of gasoline w/10% ethanol = 3,072,000 gallons of gasoline burned PER DAY for DRLs.

You can explain this one further, I must be missing something.

You are saying just the DRLs of 30 million passenger vehicles, around 10% of the nations registered passenger vehicles, account for about 1% of the entire nations gas usage a day? What does the engine of just these 30 million passenger vehicles use? 1,000,000% of the nations daily gas consumption?

[HumbleAg]

Holy crap, now I've gone from somewhat bored to totally bored.

MIchael, you obviously aren't the true mullethead (all his crap was made up), but I nominate you as an honorary mullethead just for continuing an argument no one cares about.

So, what's your take on airbags? (Please don't answer that, it was just a smart-ass comment)

[Michael1]

Originally Posted by dеiтайожни

You can explain this one further, I must be missing something.

You are saying just the DRLs of 30 million passenger vehicles, around 10% of the nations registered passenger vehicles, account for about 1% of the entire nations gas usage a day? What does the engine of just these 30 million passenger vehicles use? 1,000,000% of the nations daily gas consumption?

Here's the part you are missing. That is 30 million passenger vehicles on the road in any one hour during the 10 hours of daylight. I guess that figure could have been clearer.

Michael

[HumbleAg]

Originally Posted by Michael1

Uh, maybe for use in fog?

Hey Mullet Head, is that you? If not, you are a great stand-in.

Fog lights are for use aiding the low beam headlights in fog, not to replace them. Read the owners manual in the Mulletmobile.

I'm somewhat bored with this discussion.

[Michael1]

Originally Posted by HumbleAg

Hey Mullet Head, is that you? If not, you are a great stand-in.

Fog lights are for use aiding the low beam headlights in fog, not to replace them. Read the owners manual in the Mulletmobile.

I'm somewhat bored with this discussion.

This is from Daniel Stern, a lighting consultant:

"To answer the original question of whether fogs are meant to be used with
or without headlamps:

In general, it is not appropriate and not safe (and in many places, not
legal) to drive with only parking and fog lamps at any time. In fact, it's
a poor idea (and in many places, not legal) to drive with fog lamps (even
with headlamps on) unless weather conditions warrant their use. Some
jurisdictions explicitly permit fog lamps to be used "in lieu of" (rather
than "in supplement to") headlamps when weather conditions so warrant.
Current human-factors research (e.g. Sivak and Flannagan, 1997) shows that there are situations (extremely adverse weather conditions) in which running with properly-designed fogs and full position marking lamps (parking lamps, sidemarkers, taillamps) but no headlamps can be of great advantage. However, the local laws that prohibit the use of fogs without headlamps aren't likely to change until Federal Motor Vehicle Safety Standard 108 (and Canadian Motor Vehicle Safety Standard 108) are modified to contain a meaningful performance standard for fog lamps.

More detail:

Fog and driving lamp performance is not regulated under FMVSS 108 or any
other Federal standard. The only proviso is that items unregulated by
FMVSS may not be installed in a manner that would interfere with the
function of FMVSS-required equipment. For instance, fog lamps may not
obscure or glare-out the turn signals or cover-up the headlamps. The lack
of a precise performance specification for fog and drive lamps means that
a manufacturer can call just about anything a "fog" lamp (or a "driving")
lamp. Many of the factory fog lamps on US and Canadian roads do little,
if anything, to illuminate the road--though many of them do a fine job of
illuminating other drivers' retinas. In Europe, fog and drive beams are
required to conform to specific beam pattern criteria. The toy plastic
items we get here are not acceptable over there. Because "fog lamp" has a
meaningful definition in Europe and it is possible to count on such a lamp
producing at least a specific performance level, fog lamp usage laws allow
more flexibility to use the lamps in such a manner as to maximize their
benefit.


NHTSA is currently working with ECE (European) regulators to devise a fog
lamp beam standard that is said to be an improvement even on the
already-good European beam. It's a step in the right direction,
certainly, but I remain skeptical until I actually see such a lamp.
We've been stuck with too much really bad lighting from US regulators for
too long for me to trust what they say."

Michael