Findings of the Ad Hoc Review Committee

Submitted March 22, 2009

The comments that follow are submitted on behalf of an Ad Hoc Review Committee that has spent the past six weeks analyzing and debating the MLO draft released on February 10th. The Committee is a broadly based group with diverse backgrounds, and its members represent, cumulatively, decades of experience working on dark-sky legislation.

The Committee reviewed and debated the MLO draft within a framework of a dozen topics:

  1. Comprehension/complexity
  2. Language in general
  3. Scope
  4. Is the metric appropriate?
  5. “BUG” rating system
  6. Lighting zones
  7. Lighting controls and curfews
  8. Exemptions/exclusions
  9. Is it tough enough?
  10. Is it manageable from the standpoint of enforcement?
  11. Does this draft respond to 2004 FixTheMLO recommendations?
  12. Do we believe this will curtail light pollution?

The Committee’s findings follow under topical headings. The members respectfully request that these conclusions be given serious consideration by the Task Force and the IDA Board.

Topic 1: Comprehension/complexity

Taken as a whole, the MLO draft is too complicated by far. No lighting ordinance will help curtail light pollution if it cannot be understood by

  1. Members of the public who would need to support it and elected officials who would need to enact it;
  2. Planning and zoning personnel that would implement it and the people responsible for enforcement (police/code enforcement/building inspectors/judges);
  3. Developers and property owners.

Even if something like this draft were to be enacted, its complexity could end up stifling growth as developers, deterred by the difficulty and expense of compliance, seek other sites.

We need to keep in mind that getting any outdoor lighting ordinance enacted is generally an uphill struggle. If IDA adopts a model that requires localities to hire lighting professionals, the chances of an ordinance being enacted by a given locality will plummet; if a locality does proceed, it will likely be with a “home grown” ordinance. This may not necessarily be a bad thing, but in this case MLO will have served no useful purpose.

Topic 2: Language in general

A number of definitions are in need of improvement.

Adjacent grade:
Which is it to be, directly under the fixture or nearest thereto? That can vary by several feet.
Fully shielded luminaire:
Replace “lower photometric hemisphere” with plain-English description.
Glare:
Reflected glare is nowhere addressed, and any discussion of glare should include it.
Hardscape perimeter:
What is the logic of adding building perimeter to outside perimeter of the hardscape area?
Lamp watts:
Self-ballasted CFL’s do not have “external auxiliaries” therefore, the word “external” should be dropped.
Landscape lighting:
No reason why landscape lighting isn’t and couldn’t be mounted on poles. Strike “not mounted to poles or buildings.”
Light pollution:
Existing definition is outdated in its narrowness and inconsistent with what IDA is using. Replace with: “Any adverse effect of artificial light including, but not limited to, glare, light trespass, skyglow, energy waste, compromised safety and security, and impacts on the nocturnal environment."
Partly shielded luminaire:
(1) Unclear. (2) There are many possible designs that would logically be described as partly shielded. Does it make sense to limit this to those that have a “translucent shade” on top? (3) Replace “upper photometric hemisphere” with plain English.
Sky glow:
It is not the illumination of clouds, but rather clouds that are illuminated. Replace with: “Clouds, moisture, and airborne matter illuminated by artificial lighting.”
Uplight:
What is “the horizontal plane”? Needs to be defined.

The following definitions are not used in the MLO and should be deleted:

  • Improved area
  • Intended manner
  • Obtrusive light
  • Service yard

The following definitions for commonly used terms are unnecessary and should be deleted:

  • Opaque
  • Project
  • Property line
  • Public right-of-way
  • Translucent
  • Urban park

In addition, the existing Preamble is unsatisfactory because all of the dark-sky concerns are presented as subordinate to the positive descriptions of outdoor lighting. We recommend the following language to reflect a better balance:

“The purpose of this Ordinance is to establish regulations for outdoor lighting that will conserve energy and resources to the greatest extent possible, will minimize adverse offsite impacts including light trespass and glare, will reduce harmful impacts of artificial night light on flora and fauna, and will help preserve the dark night sky for its inspiration, for its historic and cultural significance, and for astronomical observation, while permitting reasonable uses of outdoor lighting for nighttime safety, utility, productivity, enjoyment and commerce.”

Placing all tables with the text concerning them would make this draft a bit easier to comprehend.

Topic 3: Scope - Is anything missing? Should anything be dropped?

We suggest the following additions:

  1. Plan submission requirements
    What information about outdoor lighting does the Authority require? This should be spelled out in the ordinance to avoid submissions that are inadequate, irrelevant, or otherwise off target.
  2. Roadway lighting
    Roadway lighting should not be excluded from MLO, which should require all new/replacement streetlights to be fully shielded.
  3. Subdivision lighting
    Subdivision lighting is normally part of the Planning Board review process and therefore should logically be covered here.
  4. Provisions for modifying/updating
    A clear path should be laid out for modifying and/or updating MLO.

In addition, VII.A, Amortization, should be replaced with the following: “All outdoor lighting shall comply with this Code by an amortization date, to be determined by the Authority, of 5 to 10 years after the Code becomes effective.”

Topic 4: Is the metric appropriate?

Lumens is the logical metric for an ordinance governing light pollution. The use of both lumens and watts in Table D adds unnecessary complexity.

While the intent here may have been to make the table “homeowner friendly,” the user would need to understand lumen equivalents in any event in order to comply with the directive to “not exceed the lower of either the allowed watts or lumens.” It is recommended that wattage levels be removed from the table and that a footnote be added containing lumen equivalents for common incandescent wattages.

We note in passing that the numbers currently in Table D do not appear to represent the lumen equivalents commonly cited for incandescent wattages.

Topic 5: “BUG” rating system

The principal problems noted with the BUG system are:

  • There is no explanation of how the values in the Addendum were arrived at. What are the guiding principles? Without knowing this, there is no way to determine whether these values make sense. We know, for example, that “uplight low” (90-100 degrees) travels through more atmosphere and thus causes more skyglow than “uplight high” (100-180). Shouldn’t Table A-2 of the Addendum reflect that?
  • It is too complicated and confusing to be understood by the people who would need to enact outdoor lighting legislation. Because the ratings derived from the Addendum are dependent on values in several cells, there’s no way to describe what they mean. “Engineered to death” is one description offered for this system.
  • The column headings in the Addendum should be changed to delete the zeros--i.e., the first column in the first table should be headed “B1” rather than “B0.” The zero designation is irrational (therefore confusing), since there are positive values in every column.
  • The Table C footnote regarding mounting orientation may not be clear. Perhaps a better version would be, “The luminaire must be mounted so that the least amount of light is aimed toward the nearest property line.”
  • Table C permits uplight everywhere except Lighting Zone 0. This is unacceptable and has already been seized upon by NEMA to show that IDA no longer believes fully shielded fixtures should be required.
  • Isn’t glare to some degree a function of mounting height? Table C does not take this into account.
  • Is this enforceable? How would post-construction compliance be assessed? How could anyone determine the BUG rating once a fixture was installed?
  • Last but by no means least, the data do not exist to implement this scheme! Although some manufacturers are including the Luminaire Classification System data in their photometric reports, others are not yet even complying with the IES requirements to detail light above the horizontal.

Topic 6: Lighting zones

Illuminance levels should be based on the visual tasks and activities involved for a particular use, not on the LZ in which the task is being performed. For example, if the amount of light allowed in LZ2 for a parking lot is based on IES RPs (as we have heard), then there is simply no good reason...particularly from the IDA perspective...to allow more in any zone.

This MLO draft, however, insists on lockstep increments for every application as Lighting Zone increases. This is antithetical to dark sky principles and even good lighting principles and, what may be worse, appears to endorse the misbegotten notion that “more light is better.” Furthermore, the very amorphous LZ definitions provided appear designed to perpetuate existing ambient lighting levels everywhere--scarcely the object of an outdoor lighting ordinance!

The LZ provisions in this MLO draft are unacceptable until such time as the whole concept is revisited and redone from the bottom up.

Topic 7: Lighting controls and curfews

We recommend the following changes for Section III.D.1:

  • In the description of control devices, add “switching devices shall have battery or spring backup and shall be capable of compensating for annual time changes.”
  • There needs to be more clarity on when various control devices are acceptable. Obviously, a photocell is inadequate where lighting is not to operate from dusk until dawn, but the existing language does not make that clear.
  • Delete the exemption for “lighting under canopies.” Canopy lighting is one of the big “moth-effect marketing” offenders and should be subject to the same controls/curfews as any other outdoor lighting.
  • In 1.b, change “and similar conditions” to “and similarly enclosed facilities.” It needs to be clear that the uncovered top of a parking ramp is not to be lighted during daylight hours.

We recommend the following changes for Section III.D.2:

  • If lights are not extinguished altogether, total outdoor lighting lumens should be reduced by 70%, not the 30% presently shown.
  • This section should spell out that in addition to Lighting Zone, curfew times should relate to when business/activity ceases for the day--e.g., “10:30 p.m. or 30 minutes after close of business.”

Topic 8: Exemptions/exclusions

Streetlighting is a very large contributor to light pollution almost everywhere. In addition, a municipality contemplating adoption of a lighting ordinance would do well to set a good example for residents and businesses that will be expected to comply. Roadway lighting should not be excluded from MLO, which should require all new/replacement streetlights to be fully shielded.

Other issues in III.B:

c. Some limits should be placed on lighting of public monuments and statuary, if only to require that lighting be shut off at a reasonable hour and be shielded and aimed to minimize stray light.

d. There is no basis for assuming that a sign ordinance is already in place in every jurisdiction or that such ordinance addresses sign lighting. At minimum, MLO should require that externally illuminated signs be lit from the top down.

g. It is not clear whether the swimming pool exemption is for under- or above-water lighting. Swimming pool apron lighting should not be exempt.

j. Remove this exemption. There is no way to implement or enforce a standard when there is no way to independently define whether a light is being used “solely for security” or not. And in the vast majority of jurisdictions, there is no way to keep tabs on whether the required motion sensors are working, broken, or turned off.

k. There is no reason to exempt landscape lighting just because it’s on a timer, particularly since no lumen limits are stipulated in Table B.

There are also problems in the Lighting Controls section, D.1:

a. As noted elsewhere, canopy lighting should not be exempt.

b. Parking garages should not be exempt unless they are fully enclosed.

And in the Curfews section, D.2:

a. The language is not clear. What if there are also a dozen non-conforming fixtures on the same site?

c. Insert the word “normal” before “lighting.”

Topic 9: Is it tough enough?

This question has already been partially addressed under several other headings. Of particular concern are the Lighting Zone scheme, which appears designed to perpetuate existing light levels, and the endorsement of uplighting built into the BUG ratings. More fundamentally, the MLO fails to provide any warrants or otherwise provide guidance for when not to light or when reflective materials might suffice.

There has been speculation that the LZ2 lighting levels are based on IES Recommended Practices, but as with other aspects of this draft, the Task Force has declined to share any information on the guiding principles of the lumen allowances. If the LZ2 levels do indeed reflect IES RPs, then all values greater than these are too much.

Topic 10: Is it manageable from the standpoint of enforcement?

As already noted, this MLO is too complicated by far.

An ordinance of this sort would typically be used by the following parties:

  • Governing body
  • Planning board/commission
  • Planning staff
  • Municipal engineer (probably civil, not electrical)
  • Developer
  • Lighting designer
  • Lighting manufacturer who does gratis lighting layouts
  • Contractor/installer
  • Building inspector
  • Code enforcement officer
  • Zoning appeals board

and during the following phases of a project:

  • Lighting design
  • Site plan review
  • Conditional use or special exception review
  • Building permit review
  • Construction monitoring
  • Occupancy permit review
  • Responding to lighting complaints

Unless the MLO can be fully understood by all of these people and through all of these processes, it cannot be enforced. The present MLO fails this test.

Topic 11: Does this draft respond to 2004 FixTheMLO recommendations?

In 2004 the FixTheMLO group offered a number of suggestions for improving the MLO draft then under review. Among the most important were:

  1. Make it “user friendly.”
  2. Use the right metric.
  3. Provide guidance for phasing out pre-existing non-conforming lighting.
  4. Include streetlighting.
  5. Establish a “gold standard” for curtailing light pollution.

In the current draft we see some progress on Items B and C. However, MLO still omits streetlighting and falls far short of anything that could be considered a “gold standard.” And it has become substantially more complicated and therefore less potentially useful to the kinds of municipalities most interested in curtailing light pollution.

Topic 12: Do we believe this will curtail light pollution?

It has been suggested that the LZ2 lighting levels in this draft are intended to reflect IES Recommended Practices. Very few would argue that the RPs allow too little light; some would argue that many RP values are “generous.”

The problem with using this approach for the MLO is that it is based on the critical yet unfounded assumption that good lighting practice as defined by IES is the same thing as dark-sky protection.

This has never been shown to be true. In fact, a world lighted everywhere to IES “best practice” might be immensely brighter and more light polluted than even today’s largely unregulated world, because it appears likely that sites “under-lighted” according to IES RPs are vastly more common than those “over-lighted” (as was shown by the California Base-Line Study).

As the FixTheMLO group wrote in 2004, any model ordinance promulgated by IDA should establish criteria that will be the “gold standard” of night-sky protection. If a community finds the MLO overly strict, it can simply loosen the requirements as it sees fit for local application. The huge danger of a watered down MLO is that it will become almost impossible for municipalities to enact something stricter than that which has been blessed by IDA.