State of California
AIR RESOURCES BOARD
Notice of Public Availability of
Revised Staff Report: Initial Statement of Reasons (ISOR)
PUBLIC HEARING TO CONSIDER AMENDMENTS TO REGULATIONS
FOR THE STATE AMBIENT AIR QUALITY STANDARD FOR OZONE
Public Hearing Date: April 28, 2005
Public Availability Date: October 27, 2005
Deadline for Public Comment: November 11, 2005
At its April 28, 2005, public hearing, the Air Resources Board (the Board) approved amendments to sections 70100,
70100.1, and 70200, title 17, California Code of Regulations (CCR), which established a new 8-hour-average standard
for ozone at 0.070 parts per million (ppm) and retained the existing 1-hour-average standard for ozone of 0.09
ppm. The ambient air quality standards for ozone reflect the composition and duration of ozone with its undesirable
effects, and essentially define healthy air for that pollutant.
One of the rulemaking documents made available March 11, 2005 in support of the proposed amendments was a four-volume
Staff Report: Initial Statement of Reasons (the Staff Report). The Staff Report included an informative health
benefits discussion to inform people in practical terms what effect attaining the ozone standards would have. At
the hearing, the staff presented a modified health benefits analysis, using a different methodology than the analysis
presented in the Staff Report released on
March 11, 2005. The modifications were developed in response to public comments received on the Staff Report. The
health benefits analysis explains the public health impacts associated with current ozone exposures and the benefits
from reducing ozone exposures to the level of the State's ozone ambient air quality standards.
The staff's modified methodology of the health benefits analysis led to modified results, which were presented
at the April 28, 2005, Board hearing. As a result, staff now estimates that current ozone exposure results in approximately
630 premature deaths per year, rather than the 580 premature deaths per year figure presented in the Staff Report.
Other health endpoints have changed as well. In addition, at the hearing, staff presented the incremental health
benefits of attaining the federal and California ozone standards, which had not been included in the Staff Report.
At the hearing, the Board directed staff to prepare revisions to the Staff Report in order to incorporate the health
benefits analysis modifications presented at the April Board hearing, and to make the revisions available for a
supplemental public comment period. Corrections of typographical errors in the titles to several references as
identified in the Staff Report are also being made available. The modifications are shown in underline/strikeout
type so they can be readily identified. While the revised version of the Staff Report is being added to the rulemaking
record, it does not replace the Staff Report released on March 11, 2005, which remains part of the record. The
purpose of this action is to present an update of the Staff Report to reflect staff's current methodology for calculating
health impacts of ozone exposure, and to present the modified health benefits results.
Appended to this notice is Board Resolution 05-31 (attachment 1) approving sections 70100, 70100.1, and 70200.
The modifications to the Staff Report do not necessitate any changes to the ozone standards as set forth in these
sections because the proposed amendments to the ozone standard are not based on the health benefits analysis. Revisions
to the staff report, Attachment 1 to this notice and all associated regulatory documents for this item are available
online at the following ARB internet site: http://www.arb.ca.gov/regact/ozone05/ozone05.htm.
Printed copies are available from Deborah Drechsler, Ph.D., Research Division, at 916-323-1526
In accordance with section 11346.8 of the Government Code, the Board directed the Executive Officer to make the
modified text of the Staff Report available for public review and comment on the modifications for a period of
at least 15 days, and to consider any comments received during this period before taking final administrative action
to adopt the regulatory action as approved by the Board. Due to an oversight, Resolution 05-31 as adopted referred
to approximately 580 premature deaths per year associated with current ozone exposure rather to the updated figure
of 630 premature deaths per year presented by staff at the hearing. Staff anticipates that the Executive Order
ultimately adopting the amendments will affirm the updated figure, after which a note will be added to the Resolution
to reflect this action.
Written comments on the modifications to the Staff Report may be submitted by postal mail, electronic mail, or
facsimile as follows:
Postal Mail should be sent to:
Clerk of the Board
Air Resources Board
1001 "I" Street, 23rd Floor
Sacramento, California 95814
Electronic mail should be sent to: ozone05@listserv.arb.ca.gov
Facsimile submissions should be transmitted to: (916) 322-3928
In order to be considered by the Executive Officer, comments must be directed to ARB in one of the three forms
described above and received by ARB by 5:00 p.m. on the deadline date for public comment listed at the beginning
of this notice. Only comments relating to the above-described modifications to the text of the Staff Report shall
be considered by the Executive Officer.
Attachment