Markus Johnson
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markusja.bsky.social
Markus Johnson
@markusja.bsky.social
200 followers 75 following 400 posts
Abundant housing, abundant transit, & abundant bike lanes in our cities occupies a lot of my thinking. I'm sure other pieces of my personality will peek through over time.
Consider reading: https://medium.com/@markusjohnson2195
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markusja.bsky.social
Good news, the likely direction is to refer to IRC section of R323 as part of the proposal. I attended that part of the meeting & a L&I representative was able to join the meeting and clarify some questions that helped move things along.
November 26, 2025 at 2:50 AM
markusja.bsky.social
Please keep him away
November 25, 2025 at 4:46 PM
Reposted by Markus Johnson
mtsw.bsky.social
seems like an easy fix for the US to just adopt the sensible EU regs! bsky.app/profile/bubb...
bubbaprog.xyz Timothy Burke @bubbaprog.xyz · 2d
again, this is a Europe regulations vs U.S. regulations thing! there are a total of five pages discussing the different beam strength at different wavelengths in the european standard, whereas the DOT says headlights must be "white."
Requirements for LED modules and Road Illumination Devices (except cornering lamps) including LED modules and/or LED light sources 1. General requirements for LED modules 1.1. Each LED module sample submitted shall conform to the relevant requirements of this Regulation when tested with the supplied electronic light source control-gear(s), if any. 1.2. LED module(s) shall be so designed as to be and to remain in good working order when in normal use. They shall moreover exhibit no fault in design or manufacture. A LED module shall be considered to have failed if any one of its LEDs has failed. 1.3. LED module(s) shall be tamperproof. 1.4. The design of removable LED module(s) shall be such that: 1.4.1. When the LED module is removed and replaced by another module provided by the applicant and bearing the same light source module identification code, the photometric requirements of the headlamp or AFS system shall be met; 1.4.2. LED modules with different light source module identification codes within the same lamp housing shall not be interchangeable. 2. Manufacture of LED modules 2.1. The LED(s) on the LED module shall be equipped with suitable fixation elements. 2.2. The fixation elements shall be strong and firmly secured to the LED(s) and the LED module. 3. Test conditions 3.1. Application 3.1.1. All samples shall be tested as specified in paragraph 4. 3.1.2. The kind of light sources on a LED module shall be light-emitting diodes (LED) as defined in paragraph 2.7.1. of UN Regulation 48 in particular with regard to the element of visible radiation. Other kinds of light sources are not permitted. 3.2. Operating conditions 3.2.1. LED module operating conditions All samples shall be tested under the conditions as specified in paragraph 4.6.4. of this Regulation. If not specified differently in this Annex LED modules shall be tested inside the device as submitted by the manufacturer. 3.2.2. LED light source operating conditions All samples shall be tested under the conditions as specified in paragraph 4.6.3. of this Regulation. 3.2.3. Ambient temperature For the measurement of electrical and photometric characteristics, the device shall be operated in a dry and still atmosphere at an ambient temperature of 23 °C ± 5 °C. 3.3. Ageing Upon the request of the applicant the LED module shall be operated for 15 h and cooled down to ambient temperature before starting the tests as specified in this Regulation. 4. Specific requirements and tests 4.1. Colour rendering 4.1.1. Red content In addition to provisions as described in paragraph 4.16. of this Regulation. The minimum red content of the light of a LED module or a device incorporating LED module(s) tested (at 50 V for headlamps and AFS) shall be such that: 0.05 E ( ) V( ) d E ( ) V( ) d k 780 n m 380 n m e 780 n m 610 n m e red             where: Ee() (unit: W) is the spectral distribution of the irradiance; V() (unit: 1) is the spectral luminous efficiency; () (unit: nm) is the wavelength. This value shall be calculated using intervals of one nanometre. 4.2. UV-radiation The UV-radiation of a low-UV-type LED module shall be such that: 10 W / lm k E ( ) V( ) d E ( ) S( ) d k 5 780n m 380n m m e 400n m 250n m e UV              where: S() (unit: 1) is the spectral weighting function; km = 683 lm/W is the maximum value of the luminous efficacy of radiation. (For definitions of the other symbols see paragraph 4.1.1.). 43.1.3. 43.1.4. 43.1.5. 5.1. 5.2. Calculate the ratio between the photometric test point value determined in paragraph 4.3.1.1. and the point value determined in paragraph 4.3.1.2. Once stability of photometry has been achieved, apply the ratio calculated above to each of the remainder of the test points to create a new photometric table that describes the complete photometry based on one minute of operation. The luminous intensity values, measured after one minute and after photometric stability has occurred, shall comply with the minimum and maximum requirements. Colour The colour of the light emitted measured after one minute and measured after photometric stability has been obtained, as described in paragraph 4.3.1.2., shall both be within the required colour boundaries. The measurement of the objective luminous flux of LED module(s) producing the principal passing-beam shall be carried out as follows: The LED module(s) shall be in the configuration as described in the technical specification as defined in paragraph 3.1.3. of this Regulation. Optical elements (secondary optics) shall be removed by the Technical Service at the request of the applicant by the use of tools. This procedure and the conditions during the measurements as described below shall be described in the test report. One module of each type shall be submitted by the applicant with the light source control gear, if applicable, and sufficient instructions. Suitable thermal management (e.g. heat sink) may be provided, to simulate similar thermal conditions as in the corresponding headlamp or AFS application. Before the test each LED module shall be aged at least for seventy-two hours under the same conditions as in the corresponding headlamp application. In the case of use of an integrating sphere, the sphere shall have a minimum diameter of one meter, and at least ten times the maximum dimension of the LED module, whichever is the largest. The flux measurements can also be performed by integration using a goniophotometer. The prescriptions in CIE - Publication 84 - 1989, regarding the room temperature, positioning, etc., shall be taken into consideration. The LED module shall be burned in for approximately one hour in the closed sphere or goniophotometer. The flux shall be measured after stability has occurred, as explained in paragraph 4.3.1.2. LOWER BEAM HEADLIGHTS NUMBER AND COLOR: White, of a headlighting system listed in Table II
November 25, 2025 at 12:32 AM
markusja.bsky.social
Now I'm wondering why the use of that type of fine-grain gravel material is much more prevalent in Europe?

Better reuse of their construction materials & they build more pedestrian only areas, come to mind as plausible reasons. But visually, it fits in very nicely with the surrounding urban space
November 24, 2025 at 7:39 AM
Reposted by Markus Johnson
jackiantonovich.bsky.social
Who invests in critical thinking and who invests in an AI chatbot to help you think will be really telling.
November 23, 2025 at 4:14 PM
Reposted by Markus Johnson
jenwith1n.bsky.social
We need to be less weird about regulating e-bikes. Sure, differentiate electric motorcycles or dirt bikes. But I’ve seen throttle villainized so needlessly - all it does is give you a little push from stop to start. Let people have whatever features make them feel confident on a bike!
November 23, 2025 at 6:28 PM
Reposted by Markus Johnson
jgrantglover.bsky.social
By American standards, the Paris suburbs still have a crazy high population density. Here's a map I made a while back comparing it to Chicago.
November 22, 2025 at 9:13 PM
Reposted by Markus Johnson
nilo.bsky.social
Yeah like a lot of things in the USA we accept a lot more risk for the dominant high status way of being than the low status one. (Cars v. Trains; SFH v. Multifamily)
November 19, 2025 at 4:50 AM
Reposted by Markus Johnson
warrenjwells.bsky.social
Calling the world we have a "revealed preference" is such an incredible hand-waving of the legal framework that permeates our society.

Like, do we think poor people just *prefer* living on the wrong side of the tracks? Why don't they just move to the nice neighborhoods?
November 19, 2025 at 12:42 AM
Reposted by Markus Johnson
urbanlandrent.bsky.social
“Every fire department in continental Europe and east Asia have better firefighters than California” is their argument! Kinda crazy!
November 18, 2025 at 7:46 PM
Reposted by Markus Johnson
sandypsj.bsky.social
One of the things I got from my engagement w/ethnography for my undergrad thesis was that communities often define themselves by *what they're against*. That's why I have deep concerns with a reliance on "community" as the building block of activism and policy--it inherently risks being reactionary.
November 14, 2025 at 4:35 PM
markusja.bsky.social
Also, my suspicion is in seattle, the price spike for an extra floor happens between the 8th & 9th story, given some unique features our code.
November 14, 2025 at 3:45 AM