cold.fyi / Street Code / Open questions and known gaps

Section 21 of 22 · about 3 min read · updated October 2026

21Open questions and known gaps

The short version: What we looked for and could not pin down well enough to print. If you can source any of it, the corrections desk below wants to hear from you.

Still digging

37 things we could not source well enough

Each of these would make the guide better. Send a source and we will add it, with credit if you want it.

  • How long locate marking paint physically lasts on pavement and on grass
  • Where the name "PK nail" comes from (said to be the Parker-Kalon company)
  • Who first adopted the five-sided (pentagon) nut on fire hydrants, and when
  • Whether Boston Water and Sewer Commission installs snow flags on hydrants, and how far around a hydrant to clear snow
  • What, if anything, red versus yellow hydrant bodies officially mean in Boston (BWSC)
  • Whether Japanese street hydrant lids are officially painted yellow, and the standard design of Japan's public street hydrant sign
  • Which model fire code section lets officials require building key boxes (Knox boxes), and whether Boston requires them
  • What a red-painted curb means on a Massachusetts public street
  • Boston-specific rules on where gas meters and regulators may be placed
  • Whether any US national standard governs generic manhole cover labels such as "ELEC" and "TEL"
  • What the "CELCo" lettering on some Boston covers stands for
  • Whether Boston's district steam network uses street steam stacks like New York's
  • Exact start year of Japan's decorative manhole cover campaign
  • Standard markings and color conventions (such as yellow for gas) for gas curb-valve lids
  • Coal chute covers in Boston's Back Bay and South End, Philadelphia and New York
  • New York City rules on sidewalk cellar doors (owner duties, guards when open) and their history
  • Whether transformer vaults are the main source of heat rising from sidewalk grates
  • Lettering on Boston "FIRE ALARM" and "STREET LIGHT" covers
  • Exact UK mark and gap lengths for lane lines and hazard warning lines (which part of each 6 m or 9 m module is paint)
  • Which US states and cities require blue reflective markers for fire hydrants, and practice in New Zealand
  • The national Canadian standard (TAC Manual of Uniform Traffic Control Devices for Canada) for center line color and patterns
  • Which US states do not legally recognize unmarked crosswalks at intersections
  • The Boston design standard that governs green bike lane paint
  • The year white zigzag lines were introduced at UK pedestrian crossings
  • How Boston utility pole numbers are formatted and how residents should report a specific pole by its number
  • Boston's official street name sign color and lettering standard (BTD specs A50 and A51 not found)
  • Whether Boston or MassDOT puts a standard date or inventory label on the back of signs
  • Any federal rule on the order in which parking signs are stacked on a pole, and how the 2015 Los Angeles grid parking sign pilot turned out
  • FHWA's own national definition of the MUTCD sign code letter prefixes (only Minnesota DOT's grouping is sourced)
  • A state-by-state list of places that use colored curbs to set parking rules
  • Boston examples of historic bollards, including any reused cannon
  • Status of Boston's gas-lamp-to-LED conversion as of 2026 (how many converted, where)
  • The color of Boston's snow emergency artery parking signs
  • A city source stating BWSC ownership of hydrants and covers
  • Brick sidewalks outside the US
  • How Verizon, Comcast and Eversource label their street cabinets in Boston
  • Use of the international tsunami sign pictogram in Chile and Indonesia
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