OFFICE OF INSPECTOR GENERAL

 

Catalyst for Improving the Environment

Evaluation Report

Survey of Air Quality Information

Related to the World Trade

Center Collapse 

Report No. 2003-P-00014

September 26, 2003 
Report Contributors: Sarah Fabirkiewicz

Jim Hatfield

Chris Dunlap

Darryl Weatherhead 

Rick Beusse

Elizabeth Grossman

Abbreviations

EPA Environmental Protection Agency

HEPA High Efficiency Particulate Air

NYC New York City

OIG Office of Inspector General

OMB Office of Management and Budget

WTC World Trade Center

Cover Photo: Image from French SPOT satellite, which shows the plume from the World

Trade Center site in Lower Manhattan blowing over Brooklyn. Source: image

obtained from NASA web site - http://l7fot.gsfc.nasa.gov/NYC.html
 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

 WASHINGTON, D.C. 20460

THE INSPECTOR GENERAL

 September 26, 2003

MEMORANDUM

SUBJECT: Survey of Air Quality Information 

Related to the World Trade Center Collapse

Report No. 2003-P-00014

TO: Marianne L. Horinko 

Acting Administrator 

This memorandum transmits the results of an Office of Inspector General (OIG) survey that

gauged the public’s perception of air quality information received after the collapse of the

World Trade Center (WTC) towers. Data from this survey supplement our earlier report,

EPA’s Response to the World Trade Center Collapse: Challenges, Successes, and Areas for

Improvement (Report No. 2003-P-00012), dated August 21, 2003.

EPA communicated air quality information to the public through press releases, interviews with

print and television journalists, appearances at public forums, and posting of extensive data on

the Agency’s public web site. Concerns were raised, however, about government

communications in the aftermath of the WTC disaster and the impact these communications had

on the actions taken by the public and responders to reduce their exposure to WTC contaminants. 

More than a year after the WTC disaster, a city-wide study had not been undertaken to gauge the

effectiveness of the crisis communication efforts following September 11, 2001. To that end, the

OIG conducted a survey of New York City (NYC) residents on a variety of issues related to air

quality. Based on the survey’s response rate of 11.8 percent, the data presented in this report

represent the responses from 1,110 survey respondents, and should not be generalized to the

population of NYC.

Summary of Results

Overall, the majority of respondents wanted more information regarding outdoor and indoor air

quality, wanted this information in a more timely manner, and did not believe the information

they received.

The survey results also suggest a disconnect between government statements about air quality

and respondents’ perceptions of possible health risks from breathing the air in Lower Manhattan. 

The majority of respondents reported that they thought breathing outdoor and indoor air in Lower
Manhattan in the weeks following the WTC collapse could expose them to short- and long-term

health effects. 

Further, data indicated that contamination from the collapse of the WTC towers spread into the

homes of respondents located beyond the perimeter of the zone designated as eligible for the

EPA-led testing and cleaning program.

Our data indicated only about 1 out of 10 respondents knew about EPA’s “Response to

September 11” web site, and even fewer visited the site. The majority of respondents, however,

were aware of key WTC-related information, such as EPA’s recommendation to have

contaminated homes professionally cleaned and the EPA-led testing and cleaning program in

eligible areas of Manhattan. Despite this awareness, relatively few respondents with home

contamination had their homes tested for asbestos or professionally cleaned.

Actions Already Being Taken

EPA has initiated several actions to improve its risk communications in the aftermath of the

WTC collapse. Also, our prior report included many recommendations for improving risk

communications that the Agency has agreed to implement. As such, we have not made

additional recommendations in this report based on the survey. 

We appreciate the efforts of EPA officials and staff in working with us to develop this survey. 

If you or your staff have any questions regarding this report, please contact me at (202) 566-0847

or Kwai Chan, Assistant Inspector General for Program Evaluation, at (202) 566-0827. 

Nikki L. Tinsley 

Attachment

cc:

Thomas J. Gibson, Chief of Staff, Office of the Administrator 

Jane M. Kenny, Regional Administrator, EPA Region 2

Barry N. Breen, Principal Deputy Assistant Administrator, Office of Solid Waste and 

Emergency Response

Jeffrey R. Holmstead, Assistant Administrator for Air and Radiation

J. Paul Gilman, Ph.D., Assistant Administrator for Research and Development 

Kimberly Terese Nelson, Assistant Administrator for Environmental Information

Lisa B. Harrison, Acting Associate Administrator, Office of Public Affairs

Kathleen Callahan, Assistant Regional Administrator for New York City Response and 

Recovery Operations

Mary U. Kruger, Director, EPA Office of Homeland Security

ii
Table of Contents

Introduction ...................................................... 1

Purpose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 

Scope and Methodology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 

Survey Response Rate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 

Survey Results .................................................... 7

Section 1: Respondents’ Satisfaction With Information . . . . . . . . . . . . . . . . . . . . . . 7 

Section 2: Respondents’ Perceptions of Air Quality . . . . . . . . . . . . . . . . . . . . . . . . 9 

Section 3: Awareness of WTC-Related Information and 

 Actions Taken by Respondents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 

Limitations of Survey Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 

Observations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

Appendices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

A Survey Cover Letter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 

B Survey of Air Quality Issues After September 11, 2001 . . . . . . . . . . . . . . . . . 23 

C Sample Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25 

D Distribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 

iii

1

 From October 25 through November 1, 2001, the NYC Department of Health conducted a door-to-door survey of

residents in Lower Manhattan’s Battery Park City, Southbridge Towers, and Independence Plaza. “A Community

Needs Assessment of Lower Manhattan Following the World Trade Center Attack,” December 2001. 

1

Introduction

Purpose

This survey was undertaken in order to obtain information to satisfy objective 4 of our prior

World Trade Center (WTC) report (No. 2003-P-00012). Objective 4 sought to measure the

extent to which government communications regarding air quality and associated health risks

were:

C Rated satisfactory by the public;

C Understood and interpreted by the public; and

C Effective in getting people to take desired precautions or actions. 

After the September 11, 2001, terrorist attacks on the WTC towers, government communications

were criticized for not providing timely and accurate air quality information to the public. In

preparing the prior report, the Office of Inspector General (OIG) found that, as of September

2002, a year after the disaster, no city-wide study of the effectiveness of government

communications had been undertaken.1

 As such, the OIG conducted a survey of residents in all

five boroughs of New York City (NYC) to address the above objective.

Background

A critical component in helping the public to minimize its exposure to potential health hazards

resulting from a terrorist attack or other disaster involves effectively communicating risk

information. Armed with such information, the public can take positive steps to mitigate

potential exposures as well as take other precautions to avoid unnecessary health risks. 

Following the collapse of the WTC towers, EPA announced its intention to keep the public and

rescue workers informed about safety and health risks related to air quality. The Agency’s first

WTC-related press release, on September 13, 2001, noted that EPA:

. . . will work with the appropriate officials to ensure that rescue workers,

cleanup crews and the general public are properly informed about appropriate

steps that should be taken to ensure proper handling, transportation and

disposal of potentially contaminated debris or materials.

EPA communicated air quality information to the public through press releases, appearances at

public forums, media interviews, and its public web site. In the days and months following the
2 The earliest instance we could locate was on October 26, 2001, when the EPA Administrator recommended

professional cleaning in a televised interview on MSNBC.

2

attacks, EPA’s overriding message was that the public did not need to be concerned about

airborne contaminants. This reassurance appeared to apply to both indoor and outdoor air. 

EPA’s press releases generally did not discuss potential adverse short-term health effects or the

potential risks to sensitive populations, although Agency spokespersons orally discussed these

issues.

With respect to actions people should take to minimize their exposure to health risks, EPA’s

press releases advised residents and business owners that they could clean their own spaces if

they used “appropriate” vacuum filters and followed “recommended” and “proper” procedures,

but the releases did not define these terms. However, Agency spokespersons, including EPA’s

Administrator, recommended in televised interviews2

 and other public forums that residents

should obtain professional cleaning (by professional asbestos contractors) of indoor spaces when

dust reached certain levels. 

Scope and Methodology

To obtain information directly from the public about the impact of government communications

regarding air quality concerns following the WTC towers’ collapse, the OIG developed and

mailed out a Survey of Air Quality Issues After September 11, 2001 (see Appendices A and B). 

In accordance with the Paperwork Reduction Act, the OIG obtained approval from the Office of

Management and Budget (OMB) and solicited public comment regarding the survey through the

Federal Register. In addition, former Administrator Christine Todd Whitman reviewed the draft

survey questionnaire. Based on her input we included questions about the public’s knowledge of

EPA’s WTC response web site. The survey was pre-tested with selected citizens of NYC prior

to its delivery.

 The survey requested information from respondents in four areas: 

• Section 1: Satisfaction with outdoor and indoor air quality information received. 

Respondents were asked to rate their satisfaction on a scale of “1” (Not at All Satisfied) to

“5” (Completely Satisfied). 

• Section 2: Understanding and interpretation of air quality information received. Questions

asked respondents -- in terms of how it was affected by the collapse of the WTC towers --

their perception of air quality in Lower Manhattan in the weeks just after September 11, 2001

and at the time they took the survey in 2003. 

• Section 3: Awareness of WTC-related information and actions taken in response to the

collapse. This section asked respondents if they had taken various actions and/or precautions

in response to the dust/debris and if they were aware of certain WTC-related information. 
3 Response rate was calculated by dividing the number of surveys OIG received by the number of surveys delivered. Out of

10,000 addresses, 191 were deemed insufficient and/or undeliverable by the U.S. Postal Service and did not get delivered. 

Thus, the response rate = 1,161 / 9,809, or 11.8 percent.

3

• Section 4: Demographic information. Voluntary demographic information was requested to

detect, assess, and adjust for non-response bias within the sample, and to cross-tabulate

variances within sub-populations of interest.

Appendix C provides a detailed description of how we obtained our sample. We began sending

out the surveys on March 27, 2003, and accepted responses until July 31. We completed our

analysis of the survey responses on September 4, 2003. 

Our earlier report, EPA’s Response to the World Trade Center Collapse: Challenges, Successes,

and Areas for Improvement (Report No. 2003-P-00012), dated August 21, 2003, included many

recommendations for improving risk communications that the Agency has agreed to implement. 

As such, this report on the survey is not making any additional recommendations.

Our review was conducted in accordance with Government Auditing Standards, issued by the

Comptroller General of the United States. 

Survey Response Rate

This report is based on surveys received from 1,110 respondents who reported living in NYC as

of September 11, 2001. We actually received 1,161 responses, for an overall response rate of

11.8 percent.3

 However, the data analyzed and referred to throughout this report excludes 51 of

the 1,161 surveys received because they contained either no zip code or a zip code from outside

of NYC. Based on the response rate and a lack of information regarding certain characteristics of

non-respondents, we determined that, for purposes of this report, results from the data presented

would be limited only to the pool of survey respondents who reported living in NYC as of

September 11, 2001, and we did not draw any inferences about the overall population of the five

boroughs of NYC. 

Figure 1 depicts the distribution of respondents across NYC based on where respondents reported

living as of September 11, 2001. For purposes of drawing a sample for the survey and to be able

to analyze data by zip code, OIG defined Lower Manhattan as the area south of Broome and E.

Houston Streets.
4

53.8%

61.1%

46.2%

38.9%

79.4%

73.6%

20.6%

26.4%

62.9%

95.1%

23.8%

53.1%

29.2%

13.7%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Female Male Age18-59 Age 60+ H.S. Diploma

or Higher

Bachelor's

Degree or

Higher

English Not

Primary

NYC Population All Respondents

Figure 1: Distribution of Respondents by Where They Lived on September 11, 2001*

* Respondents were asked their five-digit zip code as of September 11, 2001, and the

number of responses by borough is based on the respondent’s address at that time. An

additional 51 surveys contained either no zip code or a zip code from outside of NYC. 

Figure 2 shows how the survey respondents compare to the population of NYC in terms of

selected demographic characteristics, including sex, age, education level, and language.

Figure 2: Demographic Characteristics of OIG Survey Respondents Compared to

Characteristics of NYC Population*

 * Source: 2000 Census 
5

Figure 2 indicates that based on the 2000 Census, females are over represented among

respondents (61.1 percent versus 53.8 percent in the NYC population). In terms of age, the

respondents are somewhat older than the actual population of NYC, with under representation of

18-59 year-olds and over representation of people aged 60 years or more. Overall, respondents

have a much higher level of education than the NYC population, with 95.1 percent having at

least a high school diploma compared to 62.9 percent in the actual population; and with

53.1 percent having a bachelor’s degree or higher compared to 23.8 percent in the actual

population. People who do not speak English as their primary language are under represented 

among respondents at 13.7 percent compared to 29.2 percent in the population.
6

 
7

Majority of respondents not satisfied with

information on air quality

Survey Results

The majority of survey respondents indicated they were not satisfied with information they

received regarding outdoor and indoor air quality. Despite reassuring statements by EPA that the

air was “safe” to breathe, the majority of respondents thought breathing the outdoor and indoor

air in Lower Manhattan could expose them to short- and long-term health risks. Most reports of

home contamination came from respondents from Manhattan and Brooklyn. The majority of

respondents knew that contaminated homes should be professionally cleaned, but few had their

residence tested for asbestos and few who reported home contamination in Manhattan and

Brooklyn had their home professionally cleaned. Furthermore, few respondents knew about or

visited EPA’s “Response to September 11” web site. Details follow.

Section 1: Respondents’ Satisfaction With Information

Section 1 of the survey asked respondents to

rate their satisfaction with various

characteristics of the information they

received about outdoor and indoor air quality

by circling a number on a scale of 1 to 5, with

“1” equaling Not at All Satisfied and “5” equaling Completely Satisfied. In our analysis, ratings

of “1” and “2” were considered dissatisfied, while ratings of “4” and “5” were considered

satisfied. The scale’s midpoint is 3.0. Table 1 displays satisfaction ratings from all respondents.

Table 1: Respondents’ Satisfaction With Information Received About Outdoor

and Indoor Air Quality in the Weeks Just After Collapse of WTC Towers

Scale:

1 = Not At All Satisfied 

5 = Completely Satisfied 

1 to 2 

(%) 

3

 (%)

4 to 5 

(%) 

Mean

Rating

Total

(no.)

Outdoor

Amount 59.4 24.0 16.7 2.3 1,051

Understandability 47.7 25.9 26.3 2.6 1,018

Timeliness 57.1 23.3 19.6 2.4 1,009

Believability 61.2 19.8 19.0 2.3 1,011

Overall 57.3 24.5 18.2 2.3 1,019

Indoor

Amount 66.1 20.1 13.8 2.1 1,029

Understandability 52.4 25.1 22.6 2.5 978

Timeliness 62.3 21.4 16.3 2.2 974

Believability 63.0 19.4 17.6 2.2 974

Overall 63.5 21.3 15.2 2.2 986

 
8

Table 1 indicates that more than half of all respondents were dissatisfied with the amount,

timeliness and believability of the information they received in the weeks just after September

11, 2001. Approximately 6 out of every 10 respondents gave a dissatisfactory overall rating for

the information they received. Respondents’ ratings of the understandability of the information

they received for outdoor air quality was slightly higher, but the average rating of 2.6 was still

below the scale midpoint of 3.0.

Respondents were also asked to rate their satisfaction with health-related information they

received in the weeks following the collapse. Satisfaction ratings were calculated for all

respondents as well as for those respondents who reported working within the perimeter of

Ground Zero between September 11, 2001, and December 31, 2001, and for those respondents

who reported living in Lower Manhattan as of September 11, 2001. Table 2 depicts how all

respondents, Ground Zero workers, and respondents from Lower Manhattan rated the healthrelated information they received. 

Table 2: Satisfaction With Information Received About Health Risks in Weeks After the

Collapse of WTC Towers for All Respondents, Ground Zero Workers, and Residents of

Lower Manhattan

Scale:

 1 = Not At All Satisfied 

 5 = Completely Satisfied

1 or 2

(%)

3

(%)

4 or 5

(%)

Mean

Rating

Total

(no.)

Explanation of possible

health threats related to

air quality

All Respondents 64.3 17.5 18.3 2.2 1,013

Ground Zero Workers 71.3 14.4 14.4 2.0 188

Lower Manhattan 68.0 15.5 16.5 2.1 194

Explanation of how to

minimize exposure to

potential health risks

related to air quality

All Respondents 65.3 17.0 17.7 2.2 1,018

Ground Zero Workers 71.0 17.2 11.8 2.0 186

Lower Manhattan 69.1 13.1 17.8 2.1 191

Explanation of health

problems one may

experience due to air

quality

All Respondents 65.0 18.1 17.0 2.2 1,014

Ground Zero Workers 70.6 16.0 13.4 2.0 187

Lower Manhattan 69.1 16.0 15.0 2.0 194

Explanation of what to

do if one experienced a

health problem related

to air quality

All Respondents 64.6 18.2 17.2 2.2 1,010

Ground Zero Workers 68.7 17.3 14.1 2.0 185

Lower Manhattan 69.3 14.6 16.2 2.1 192

Overall rating of

information received

about health risks

related to air quality

All Respondents 64.0 19.9 16.2 2.2 1,027

Ground Zero Workers 72.3 16.2 11.5 1.9 191

Lower Manhattan 71.4 14.6 14.1 2.1 192

 
9

Majority of respondents thought

breathing outdoor and indoor air in

Lower Manhattan in weeks after collapse

of WTC towers could expose them to

short- and long-term risks

21.8%

65.4%

38.1%

9.0%

41.6%

7.9%

74.7%

18.1%

69.2%

26.9%

88.8%

43.8%

6.6%

26.7%

14.1%

31.5%

11.2%

4.5%

0% 20% 40% 60% 80% 100%

Present

9/11/01

Present

9/11/01

Present

9/11/01

Need

protective

gear for

breathing

Long Term

health risks

Short Termhealth risks

Not Sure No Yes

More than 6 out of every 10 respondents reported dissatisfaction with (a) explanations of

possible health threats related to air quality; (b) how to minimize their exposure to health risks

related to air quality; (c) health problems they might experience due to air quality; and (d) what

to do if they experienced a health problem related to air quality. The mean rating among all 

respondents for overall satisfaction with health-related information received in the weeks

following the collapse was 2.2.

Among Ground Zero workers and those living in Lower Manhattan during September 2001 who

responded, more than 7 out of 10 were dissatisfied with the overall quality of health-related

information they received. For both of these groups, over two-thirds reported dissatisfaction with

explanations across all categories of health-related information, resulting in a mean rating for

overall satisfaction of 1.9 among Ground Zero workers and 2.1 for residents of Lower

Manhattan.

Section 2: Respondents’ Perceptions of Air Quality

 

Section 2 of the survey asked residents their

thoughts about the health risks associated with air

quality in Lower Manhattan in the weeks

immediately following the collapse of the WTC, as

well as their thoughts at the time they completed

the survey approximately 18 months later.

Figures 3a and 3b illustrate respondents’ perceptions of outdoor and indoor air quality,

respectively, in terms of how it was affected by the collapse of the WTC towers in the weeks just

after the collapse (shown in the figure as “9/11/01”) and at the time they completed the survey in

May-July 2003 (shown as “Present”).

Figure 3a: Respondents’ Perceptions of Exposure to Health Risks Associated with Outdoor

Air Quality in Lower Manhattan in Weeks After Collapse and at Time of 2003 Survey
10

43.2%

26.5%

66.8%

40.4%

15.9%

43.9%

6.5%

51.8%

16.4%

57.6%

22.0%

76.2%

22.0%

34.1%

14.0%

26.7%

26.2%

9.8%

0% 20% 40% 60% 80% 100%

Present

09/11/01

Present

09/11/01

Present

09/11/01

Need

protective

gear for

breathing

Long Term

health risks

Short Term

health risks

Not Sure No Yes

Figure 3b: Respondents’ Perceptions of Exposure to Health Risks Associated with Indoor

Air Quality in Lower Manhattan in Weeks After Collapse and at Time of 2003 Survey

Figures 3a and 3b show that in the weeks just after the collapse, more respondents were 

concerned about short-term health effects than they were about long-term for both outdoor and

indoor air. Almost 9 out of every 10 respondents said they were concerned about the short-term

health effects associated with outdoor air whereas approximately 7 of every 10 respondents were

concerned about long-term health risks. For indoor air, the results were similar; more than 3 out

of every 4 respondents were concerned about the short-term health effects while more than half

of the respondents were concerned about long-term health effects.

Based on the survey results in Figures 3a and 3b, it appears that respondents’ concerns about the

health risks associated with air quality subsided over time. Results further indicate that concerns

about health risks did not simply shift from “yes” to “no.” Instead, there was an increase in the

number of respondents who became unsure about outdoor and indoor health risks from

September 2001 to 2003. During that same time, respondents’ opinions about whether or not

they should wear protective gear when breathing outdoor and indoor air in Lower Manhattan

mainly changed from “yes” to “no,” and uncertainty over this issue remained relatively stable.

Figure 4 presents the perceptions of health risks from exposure to outdoor and indoor air in

Lower Manhattan in the weeks following the collapse among respondents who lived in Lower

Manhattan on September 11 and among respondents who lived in other parts of NYC at that time

(called “Rest of NYC” in the figure). In the figure, the results labeled “9/11/01” represent

respondents’ recollections of their perceptions of air quality in the weeks following September

11, 2001, while the results labeled “Present” are respondents’ perceptions of air quality at the

time they completed the survey in May-July 2003. 
11

18.2%

24.6%

78.5%

68.0%

29.0%

88.4%

88.9%

26.4%

75.6%

17.0%

58.6%

21.3%

69.5%

17.4%

53.3%

13.6%

0% 20% 40% 60% 80% 100%

Present

9/11/01

Present

9/11/01

Present

9/11/01

Present

9/11/01

Long Term

health risks

Short Term

health risks

Long Term

health risks

Short Term

health risks

Indoor Outdoor

Rest of NYC Lower Manhattan

Most reports of home contamination came

from respondents in Lower Manhattan, the

rest of Manhattan, and Brooklyn; EPA web

site not widely used; and homes often

cleaned without professional assistance

Figure 4: Proportion of Respondents Perceiving Health Risks Associated with Outdoor and

Indoor Air Quality in Lower Manhattan in Weeks Just After Collapse of WTC Towers and at

Time of Survey in 2003 -- Lower Manhattan Residents and the Rest of NYC

Section 3: Awareness of WTC-Related Information and Actions Taken

by Respondents

 

Section 3 of the survey asked respondents if

their homes had been contaminated with dust

and/or debris due to the collapse of the WTC

towers. This section also asked respondents

whether they knew about certain WTC-related

information and whether they had taken

certain actions in response to the dust and

debris created by the collapse of the WTC

towers. Respondents were asked about some specific EPA communications, such as whether

they: (a) knew about EPA’s “Response to September 11” web site, (b) visited the web site,

(c) knew that homes contaminated with dust and/or debris should be professionally cleaned, (d)

knew about the EPA-led program to test and clean eligible residences in Lower Manhattan, and

(e) had their residence professionally cleaned. 

Data indicate that contamination from the collapse of the WTC towers spread into the homes of

respondents located beyond the zone designated as eligible for the EPA-led testing and cleaning

program. The Indoor Residential Cleaning Program was available to residences located south

and west of Canal, Allen, and Pike streets, river to river. Specifically:

• Of the 180 residents of Lower Manhattan who responded, 46.7 percent (84 respondents)

reported that their residence had been contaminated with dust and/or debris due to the

collapse.
4

 The number of “yes” responses from the three remaining areas was as follows: Bronx - 1 out of 58 (1.7 percent); Queens -

5 out of 131 (3.82 percent); and Staten Island - 2 out of 44 (4.55 percent) 

12

• Of the 204 residents of Brooklyn who responded, 23.5 percent (48 respondents) reported that

their residence had been contaminated with dust and/or debris due to the collapse.

• Of the 213 respondents who lived in the rest of Manhattan, 11.3 percent (24 respondents)

reported that their residence had been contaminated with dust and/or debris due to the

collapse.4

Figures 5a and 5b show that, among respondents, the most incidents of contamination were

reported by those in Lower Manhattan, followed by Brooklyn and the rest of Manhattan. In the

figure below, the zip code appears on the first line of each box inset. On the second line, the

number of respondents answering “Yes” to contamination is followed by the number of total

respondents from the zip code.

Figure 5a: Reports of Contamination from Zip Codes in Manhattan* 

Source: Created using ESRI by the University Neighborhood Housing Program, www.unhp.org 

 *Contamination was also reported in two Manhattan zip codes north of the area shown on this map 

(2 out of 22 respondents from zip code 10025, and 1 out of 9 respondents from zip code 10027). 

With the exception of zip code 10005, the map only shows results for those zip codes in Lower 

Manhattan where at least one respondent reported contamination. Ground Zero is located within 

zip code 10280 in the map above. 
13

Figure 5b: Reports of Contamination From Zip Codes in Brooklyn*

 

Source: Created using ESRI by the University Neighborhood Housing Program, www.unph.org 

* For each zip code, the respondent’s zip code is the five-digit number; the number of respondents

answering “Yes” to contamination is followed by the number of total respondents from the zip code. 

The map only shows results for those zip codes in Brooklyn where at least one respondent reported

contamination. 
14

Few Respondents Knew About or Visited EPA’s “Response to September 11”

Web Site

According to EPA officials, one of the primary means of communicating WTC air quality-related

information to the public after September 11 was through EPA’s “Response to September 11”

web site. Figure 6 illustrates respondents’ awareness and use of the web site among all

respondents, respondents from Lower Manhattan, Brooklyn, and the rest of Manhattan.

Figure 6: Proportion of Respondents Aware of EPA’s Web Site - - All Respondents and 

Respondents From Lower Manhattan, Brooklyn, and Rest of Manhattan 

10.5%

20.4%

9.3% 9.8% 6.0%

14.5%

5.3% 4.7%

0%

20%

40%

60%

80%

100%

Knew of Web Site Visited Web Site

All Respondents Lower Manhattan Brooklyn Rest of Manhattan

Data in Figure 6 indicate that approximately 1 out of 10 of all respondents and respondents from

Brooklyn and the rest of Manhattan knew about EPA’s web site, but fewer visited the site.

Among respondents from Lower Manhattan, approximately 2 out of 10 respondents knew of the

web site and about 70 percent of those who knew of the web site visited it.

Figure 7 indicates that, among all respondents, approximately 6 out of 10 heard the message in

the weeks just after the collapse that homes contaminated with dust and/or debris should be

professionally cleaned for asbestos. More than half (58 percent) knew that some residents of

Lower Manhattan were eligible to have EPA test and clean their homes. About 6 out of every

100 respondents had their residence tested for asbestos. Among respondents from Lower

Manhattan, approximately 20 out of every 100 had their residence tested. Among respondents

from the rest of Manhattan and Brooklyn, less than 2 out of every 100 respondents had their

residence tested. 
15

60.2%

58.0%

54.9%

58.4%

58.2%

68.7%

51.2%

56.9%

5.9%

21.6%

1.7%

1.3%

0%

20%

40%

60%

80%

100%

Heard About

"Profes s ional

Cleaning"

Knew of EPA's

Tes t/Clean Program

 Had Residence

Tes ted

All Res pondents Lower Manhattan Brooklyn Res t of Manhattan

Figure 7: Proportion of All Respondents, Respondents from Lower Manhattan, Brooklyn,

and Rest of Manhattan Who Were Aware of the Need for Professional Cleaning and of the

EPA-Led Testing and Cleaning Program, and Had Their Residences Tested for Asbestos

Respondents who reported that their home was contaminated with dust and/or debris due to the

collapse (see Appendix B, survey question 3.e.) were further asked whether or not they had taken

certain cleaning precautions, including using professional assistance to clean their home,

cleaning without professional assistance, or using a HEPA (High Efficiency Particulate Air)

vacuum to clean their home. Figure 8 depicts these cleaning activities among respondents from

Lower Manhattan, Brooklyn, and the rest of Manhattan who reported home contamination. 

Figure 8: Proportion of Respondents in Contaminated Homes Who Had Their Home

Professionally Cleaned, Cleaned Without Professional Assistance, or Used HEPA Vacuum* 

38.3%

2.1%0.0%

70.3% 66.0% 66.7%

53.8%

28.3%

25.0%

0%

20%

40%

60%

80%

100%

Professionally

Cleaned

Cleaned, Not

Professional

HEPA Vacuum

Used

Lower Manhattan Brooklyn Res t of Mahnattan

*Some respondents reported that their residence was cleaned both with and without professional assistance.
16

Data in Figure 8 indicate that about 4 in 10 of the Lower Manhattan respondents who reported

home contamination cleaned their homes with professional assistance. Approximately 2 percent

from Brooklyn did so, and no respondents from the rest of Manhattan who reported home

contamination used professional assistance to clean their home. At least two-thirds of

respondents from each of the three areas indicated they had cleaned their residence but did so

without the use of professional assistance. 

Section 3 also asked respondents whether they took certain health-related actions in response to

the dust and debris created by the collapse of the WTC towers, such as whether they wore or

purchased protective breathing gear they normally would not have, or whether they visited a

health professional for symptoms they believed were related to air quality after the collapse. 

Figure 9 depicts the actions of all respondents, as well as the actions taken by respondents from

Lower Manhattan, Brooklyn, and the rest of Manhattan. Figure 9 also shows the health-related

actions taken by respondents who worked within the perimeter of Ground Zero between

September 11, 2001, and December 31, 2001.

Figure 9: Proportion of Respondents Who Wore or Purchased Protective Gear

or Visited a Health Professional 24.8% 20.4% 48.0%

36.6%

20.5%20.7%

20.3%

14.0%

41.6%

35.4%

0%

20%

40%

60%

80%

100%

All

Respondents

Low er

Manhattan

Brooklyn Rest of

Manhattan

Ground Zero

Workers

Wore/Purchased Protective Gear Visited Health Professional

Among all respondents, approximately 1 out of 4 reported wearing or purchasing protective

breathing gear, such as a mask. Approximately 1 out of 5 of all respondents visited a health

professional due to health problems they believed were due to air quality following the collapse.

Among respondents from Lower Manhattan, approximately 1 out of 2 reported wearing or

purchasing protective breathing gear in response to dust and/or debris created by the collapse,

and approximately 4 out of 10 visited a health professional. Among Ground Zero workers,

approximately 4 out of 10 wore or purchased protective breathing gear and about 1 out of 3

visited a health professional for problems they believed were related to air quality following the

collapse. 
17

Limitations of Survey Results

Most important among the limitations associated with the OIG’s survey is the low response rate –

less than 12 percent. The low response rate limits our ability to generalize survey results to the

population of NYC with sufficient confidence. Reasons may vary as to why potential

respondents and/or certain groups of demographically similar people opted not to complete and

return the survey. For some potential respondents, the urgency, and possibly the relevancy, of the

matters covered in the survey could have been affected due to the passage of time between the

collapse of the WTC towers and when the survey was administered. The first survey forms were

distributed more than a year and a half after September 11, 2001. It is possible that one’s

opinions about air quality information may have weakened or intensified, depending on one’s

experiences, during that time. Thus, data could be skewed toward the positive or negative

extremes. 

Another limitation associated with this survey is that some survey questions required respondents

to recollect events and experiences that occurred over a year and a half ago from the time they

took the survey. The tragic and striking nature of this event and the fact that some cleanup

activities were still ongoing in parts of NYC at the time our survey was conducted may mitigate

the likelihood of faded memories, but it is also possible that respondents’ recollections may have

faded or been skewed over time. 

Further, although we asked that the person who most recently celebrated a birthday respond to

the survey, because it was a mail survey we cannot be certain that this occurred. Therefore, even

though the households were randomly selected, we cannot be sure that respondents from within

each household were selected at random as requested in the survey cover letter
18
19

Observations

Data from the survey suggest that the majority of respondents were generally dissatisfied with the

amount, timeliness, believability, and overall quality of the information they received in the

weeks just after the collapse of the WTC towers for both outdoor and indoor air quality. More

respondents reported dissatisfaction when asked specifically about health-related information,

suggesting that potential health risks related to air quality was an area of particular concern.

Despite reassuring statements about air quality following the collapse of the WTC towers, the

majority of respondents living in Lower Manhattan and the rest of NYC believed that there were

health risks associated with breathing outdoor and indoor air in Lower Manhattan. In the weeks

following the collapse, more than 3 out of 4 respondents thought that there were short-term

health risks associated with breathing outdoor and indoor air in Lower Manhattan, and more than

half of respondents thought that breathing outdoor and indoor air in Lower Manhattan could

expose them to long-term health risks. In the period just after the collapse until 2003, data

indicate that immediate concerns over air quality in Lower Manhattan subsided; however, over

time, substantially more respondents became unsure about whether or not breathing outdoor and

indoor air in Lower Manhattan could expose them to health risks.

The responses suggest that one of EPA’s major sources of information, its “Response to

September 11” web site, was largely unused. Only about 10 percent of the respondents knew

about EPA’s web site, and even fewer actually visited the site. Approximately 6 out of 10

respondents had heard that residences contaminated with dust and debris should be

professionally cleaned for asbestos, and knew about the EPA-led program to test and clean for

asbestos in certain residences in Lower Manhattan. However, despite this awareness, less than

6 percent of all respondents had their residence tested for asbestos. 

Most reports of residential contamination came from respondents in Lower Manhattan, Brooklyn,

and the rest of Manhattan. Among respondents from these areas who reported home

contamination, relatively few reported having their residence professionally cleaned.
 

 

20
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON, DC 20460

THE INSPECTOR GENERAL

February 28, 2003

Dear New York City Resident:

It has been over one year since the terrorist attacks on the World Trade Center, yet concerns

about New York City’s air quality still remain. The Office of Inspector General would like to

know your opinion of the air quality information you received following the attacks. By 

completing and returning the enclosed survey you can help us determine whether the U.S.

Environmental Protection Agency (EPA) needs to improve the way it responds to disasters.

This survey should take 10 minutes or less to complete. 

Please be assured that all responses are confidential. Your name will not be linked to your

responses and individual answers will not be revealed. For statistical purposes only, we ask that

the survey be completed by someone residing in the household who is 18 years of age or older,

and is the person who most recently celebrated a birthday. Following these instructions will

ensure that our results are as meaningful as possible. 

A pre-addressed, postage paid envelope has been provided for you to return your completed

survey. We appreciate your prompt response. If you have any questions about this survey,

please call us at 1-800-846-3117.

Thank you in advance for your time and cooperation. In appreciation, we will send all 

households a postcard providing them with a web address and phone number for accessing the

survey results. 

You may be interested in knowing more about the Office of Inspector General. We conduct

independent reviews of EPA programs and activities. To learn more about our office, please

visit our website at http://www.epa.gov/oigearth.htm. 

Sincerely,

Nikki L. Tinsley

Inspector General 

Si desea recibir esta encuesta en español, por favor llama a 1-800-846-3117.

If you wish to receive this survey in Spanish, please call 1-800-846-3117.

Appendix A

21
Completing questions on the survey should take approximately 10 minutes or less. The total public reporting burden for this survey is estimated to average 15 minutes per respondent as a one-time-only burden. Burden means the total time, effort, or financial resources expended by persons to generate, maintain, or disclose or provide information to or for a Federal agency. This

includes: the time needed to review instructions; develop, acquire, install, and utilize technology and systems for the purposes of

collecting, validating, and verifying information; processing and maintaining information; disclosing and providing information;

adjusting the existing ways to comply with any previously applicable instructions and requirements; training personnel to be able

to respond to a collection of information; searching data sources; completing and reviewing the collection of information; and,

transmitting or otherwise disclosing or reporting on the information. An agency may not conduct or sponsor, and a person is not

required to respond to a collection of information unless it displays a currently valid OMB control number. The OMB control

numbers for EPA’s regulations are listed in 40 CFR Part 9 and 48 CFR Chapter 15. 

Send comments on the Agency’s need for this information, the accuracy of the provided burden estimates, and any suggested

methods for minimizing respondent burden, including through the use of automated collection techniques to the Director,

Collection Strategies Division, U.S. Environmental Protection Agency (2822), 1200 Pennsylvania Ave. NW, Washington DC,

20460. Include the EPA ICR number 2094.01 in any correspondence. Please do not send completed surveys to this address, use

the provided envelope instead.

22
a. Did you think breathing outdoor air in lower Manhattan could expose you to long-term health risks, such as cancer?

In the weeks just after the collapse? Yes No Wasn’t Sure NA

How about outdoor air now? Yes No Not Sure NA

b. Did you think breathing indoor air in lower Manhattan could expose you to long-term health risks, such as cancer?

In the weeks just after the collapse? Yes No Wasn’t Sure NA

How about indoor air now? Yes No Not Sure NA

c. Did you think breathing outdoor air in lower Manhattan could expose you to short-term health problems, such as coughing, sore throat, 

or asthma attacks?

In the weeks just after the collapse? Yes No Wasn’t Sure NA

How about outdoor air now? Yes No Not Sure NA

d. Did you think breathing indoor air in lower Manhattan could expose you to short-term health problems, such as coughing, sore throat, 

or asthma attacks?

In the weeks just after the collapse? Yes No Wasn’t Sure NA

How about indoor air now? Yes No Not Sure NA

e. Did you think you should have worn protective gear, such as a mask, when breathing outdoor air in lower Manhattan?

In the weeks just after the collapse? Yes No Wasn’t Sure NA

How about wearing it now? Yes No Not Sure NA

f. Did you think you should have worn protective gear, such as a mask, when breathing indoor air in lower Manhattan?

In the weeks just after the collapse? Yes No Wasn’t Sure NA

How about wearing it now? Yes No Not Sure NA

Survey of Air Quality Issues After September 11, 2001

EPA Office of Inspector General - 1200 Pennsylvania Ave. NW, Washington, DC 20460

Instructions: Listed on the front and back of this page are three main topics relating to air quality. Some of the main topics ask you

to think about specific times, such as “just after the collapse.” Below each of the main topics are several questions. Please respond

to each question by choosing the response that best reflects your thoughts or actions during the specified time period. Please

complete the front and back of this survey. Circle “NA” (not applicable) if you have no response because a question does not

apply to you.

2.) Please circle the response for both time periods that best reflects your thoughts about air quality in terms of how it was

affected by the collapse of the World Trade Center towers:

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

1 2 3 4 5 NA

Completely

Not at All

Satisfied

Satisfied

PLEASE TURN PAGE OVER TO COMPLETE SURVEY

a. The amount of information I heard or received about outdoor air quality

b. The amount of information I heard or received about indoor air quality

FOR THE INFORMATION YOU HEARD OR RECEIVED, PLEASE RATE:

c. The “understandability” of information I heard or received about outdoor air quality

d. The “understandability” of information I heard or received about indoor air quality

e. The timeliness of information I heard or received about outdoor air quality

f. The timeliness of information I heard or received about indoor air quality

g. The “believability”of information I heard or received about outdoor air quality

h. The “believability”of information I heard or received about indoor air quality

i. My overall rating of information I heard or received about outdoor air quality

j. My overall rating of information I heard or received about indoor air quality

k. Explanation of possible threats to my health related to air quality

l. Explanation of how to minimize my exposure to potential health risks related to air quality

m. Explanation of health problems I might experience due to air quality

n. Explanation of steps I should take if I experienced health problems related to air quality

o. My overall rating of information I received about health risks related to air quality

1.) Please rate your satisfaction with the information you heard or received about air

quality in the weeks just after the collapse of the World Trade Center towers:

OMB#2020-0027 Expires: 5/31/03

Appendix B

23
Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

Yes No Not sure NA

3.) Please circle the response that best describes the actions you took in response to dust or debris created by the collapse of 

the World Trade Center towers and your awareness of certain WTC-related information:

4.) Thank you for your help so far. There are only a few more questions to go. The following information is optional, but it

will help us to make sure that everyone’s opinion is included.

a. How many children under the age of 18 lived in your home as of September 11, 2001?

None 1 2 3 4 5 or more

b. Not counting you, how many adults between the age of 18 and 60 lived in your home as of September 11, 2001?

None 1 2 3 4 5 or more

c. Not counting you, how many adults over the age of 60 lived in your home as of September 11, 2001?

None 1 2 3 4 5 or more

d. What is your age? _______ years old

e. What is your gender? Female Male

f. What was your 5-digit zip code as of September 11, 2001? ___ ___ ___ ___ ___

g. Which choice best represents the area in which you worked during the month of September, 2001? (pick one)

Manhattan: South of Canal or Pike St. Bronx Connecticut

Manhattan: On Canal or Pike to South of 14th Brooklyn New Jersey

Manhattan: On 14th to 42nd Queens Other: ________________________

Manhattan: On 42nd to top of Manhattan Staten Island

h. Between 9-11-01 and 12-31-01, did you ever work within the perimeter of Ground Zero? Yes No

i. What is the highest level of education you have completed?

Less than High School High School Diploma Some College Bachelor’s Degree

Post-Grad. Degree Associate’s Degree Tech/Vocational Degree Other: ________________________

j. Is your primary language English? Yes No

Thank you for completing our survey. Please use the pre-addressed, postage-paid envelope to return your responses.

If you have further comments regarding the issues covered in this survey, please contact our office at 1-800-846-3117 or write to us at EPA

Office of Inspector General, 1200 Pennsylvania Ave. NW, Washington, DC 20460.

a. I wore or purchased protective gear, such as a mask, that I normally would not have.

b. I visited a health professional for health problems I believed were related to air quality.

c. A HEPA vacuum was used to clean the carpeting and/or rugs in my residence.

d. My residence was tested for asbestos.

e. My residence was contaminated with dust/debris due to the collapse. (If you answer

“No” or “NA”, skip to m.)

f. My residence was cleaned for dust/debris with professional assistance.

g. My residence was cleaned for dust/debris without professional assistance.

h. The floors and surfaces in my residence were wiped for dust/debris with a wet cloth.

i. All of the clothes in my residence were laundered due to dust from the collapse.

j. I have permanently vacated my residence due to dust/debris from the collapse. (If you 

answer “Yes”, skip to m.)

k. I temporarily (at least 24 hrs) vacated my residence due to dust/debris from the collapse.

(If you answer “No”, “Not sure” or “NA”, skip to m.)

l. How long was it before anyone moved back into your residence?

1 to 6 days 7 to14 days 15 to 21 days

21 days to 1 month more than 1 month No one has moved back in yet

m. I know about EPA’s “Response to September 11” Internet website.

n. I have visited EPA’s “Response to September 11” Internet website.

o. In the weeks just after the collapse, I heard that homes contaminated with dust/debris

should be professionally cleaned for asbestos.

p. I know that some residents of lower Manhattan are eligible to have EPA test and clean 

their homes.

24
25

Appendix C

Sample Details

The sampling frame – the universe from which the OIG drew its sample – consisted of all

addresses in the five boroughs of NYC (Bronx, Brooklyn, Manhattan, Queens, and Staten

Island). These areas were selected based on the proximity of residences to the WTC towers site

and their potential exposure to the dust and debris created by the collapse. The sample was

purchased from R.L. Polk Co., of Detroit, Michigan. 

A sample of 10,000 addresses was selected from this frame and divided into two sample groups

of 5,000. The proportion of addresses in each set were drawn to approximate the proportion of

households in each borough as reported in the 2000 Census. The distribution of addresses was

approximated so that Manhattan could be over sampled. Manhattan was divided into two parts:

Lower Manhattan, which, for purposes of this report, is defined to include residences south of E.

Houston and Broome Streets; and the rest of Manhattan, which is defined to include residences

north of E. Houston and Broome Streets. The final distribution of addresses in the sample was:

C Bronx: 13%

C Brooklyn: 27%

C Lower Manhattan: 13%

C Rest of Manhattan: 21%

C Queens: 22%

C Staten Island: 4%

The Survey of Air Quality Issues After September 11, 2001, was initiated with the delivery of the

pre-notification postcard on March 25, 2003 and collection was closed on July 31, 2003.

A pre-notification postcard was delivered to 5,000 addresses in the first sample group 2 days

before the surveys were mailed to inform recipients that a survey was coming and to ask for their

cooperation. This was done to promote a high response rate. In addition, a toll-free hotline was

provided in both English and Spanish for respondents to ask questions and/or request a Spanish

version of the survey. The package delivered to each address in the sample included: (1) a cover

letter printed on OIG stationery and signed by the Inspector General; (2) a one-page, doublesided survey; and (3) a postage-paid business reply envelope for the survey’s return. Appendix B

provides the survey form. Based on the response rate from the first 5,000 surveys released, the

OIG released surveys to the second set of 5,000 addresses to increase the number of responses. 

A pre-notification postcard was not sent to the second set of addresses. As a followup reminder,

a postcard was delivered to every address in both sample groups asking potential respondents to

fill out and return the survey.
 

 

26
27

Appendix D

Distribution

EPA Headquarters

Acting Administrator

Acting Assistant Administrator for Solid Waste and Emergency Response

Assistant Administrator for Air and Radiation

Assistant Administrator for Research and Development

Assistant Administrator for Environmental Information

Acting Associate Administrator, Office of Public Affairs

Comptroller (2731A)

Agency Audit Follow-up Coordinator (2724A)

Audit Follow-up Coordinator, Office of Solid Waste and Emergency Response

Audit Follow-up Coordinator, Office of Air and Radiation

Audit Follow-up Coordinator, Office of Research and Development

Audit Follow-up Coordinator, Office of Environmental Information

Audit Follow-up Coordinator, Office of Public Affairs

Associate Administrator for Congressional and Intergovernmental Relations (1301A)

 Director, Office of Regional Operations (1108A)

EPA Regions

Regional Administrators

Regional Audit Follow-up Coordinators

New York City

City of New York Law Department

EPA Office of Inspector General

Inspector General (2410)