NIOSH HEALTH HAZARD EVALUATION REPORT 

HETA #2004-0186-3011 

Claremont Flock Corporation 

Leominster, Massachusetts 

August 2006 

Vinicius Antao, MD, MSc, PhD 

Chris Piacitelli, CIH 

DEPARTMENT OF HEALTH AND HUMAN SERVICES 

Centers for Disease Control and Prevention 

National Institute for Occupational Safety and Health
ii 

PREFACE

The Respiratory Disease Hazard Evaluations and Technical Assistance Program (RDHETAP) of the 

National Institute for Occupational Safety and Health (NIOSH) conducts field investigations of possible 

health hazards in the workplace. These investigations are conducted under the authority of Section 

20(a)(6) of the Occupational Safety and Health (OSH) Act of 1970, 29 U.S.C. 669(a)(6), or Section 

501(a)(11) of the Federal Mine Safety and Health Act of 1977, 30 U.S.C. 951(a)(11), which authorizes 

the Secretary of Health and Human Services, following a written request from any employers or 

authorized representatives of employees, to determine whether any substance normally found in the place 

of employment has potentially toxic effects in such concentrations as used or found. 

RDHETAP also provides, upon request, technical and consultative assistance to federal, state, and local 

agencies; labor; industry; and other groups or individuals to control occupational health hazards and to 

prevent related trauma and disease. Mention of company names or products does not constitute 

endorsement by NIOSH. 

ACKNOWLEDGMENTS AND AVAILABILITY OF REPORT

Vinicius Antao and Chris Piacitelli of RDHETAP, Division of Respiratory Disease Studies (DRDS), 

prepared this report. Environmental field assistance was provided by Randy Boylstein of RDHETAP and 

David Sylvain of the NIOSH Hazard Evaluations and Technical Assistance Branch. Medical field 

assistance was provided by Terry Rooney and Elizabeth Lowery. Statistical support was provided by 

William Miller and Sandra White. DataChem Laboratories, Salt Lake City, Utah provided laboratory 

analytical support. Desktop publishing was performed by Amber Harton. 

Copies of this report have been sent to employee and management representatives at Claremont Flock 

Corporation, the Massachusetts Department of Public Health Occupational Health Surveillance Program, 

and the OSHA Regional Office. This report is not copyrighted and may be freely reproduced. The report 

may be viewed and printed from the following internet address: http://www.cdc.gov/niosh/hhe. Single 

copies of this report will be available for a period of three years from the date of this report. To expedite 

your request, include a self-addressed mailing label along with your written request to: 

NIOSH Publications Office 

4676 Columbia Parkway 

Cincinnati, Ohio 45226 

800-356-4674 

After this time, copies may be purchased from the National Technical Information Service (NTIS) at 5825 

Port Royal Road, Springfield, Virginia 22161. Information regarding the NTIS stock number may be 

obtained from the NIOSH Publications Office at the Cincinnati address. 

For the purpose of informing affected employees, copies of this report 

shall be posted by the employer in a prominent place accessible to the 

employees for a period of 30 calendar days.
iii 

HIGHLIGHTS OF THE NIOSH HEALTH HAZARD EVALUATION 

AT CLAREMONT FLOCK CORPORATION

The National Institute for Occupational Safety and Health (NIOSH) conducted environmental and medical surveys 

at Claremont Flock Corporation in Leominster, Massachusetts in January 2005. The Massachusetts Department of 

Public Health Occupational Health Surveillance Program had requested technical assistance to determine if there 

had been improvement in the environmental conditions and to update the health status of the workforce since a 

NIOSH evaluation in 1998, given that a new case of flock workers’ lung occurred in 2003.

What NIOSH Did

 Measured airborne dust concentrations for most 

jobs within the plant 

 Invited all employees to participate in the medical 

survey to assess health effects in relation to 

exposure to airborne particulates associated with 

flock production operations 

 Interviewed employees about symptoms and 

medical, work, and smoking histories 

 Analyzed measurements and interview results for 

associations between work exposures and health 

effects 

What NIOSH Found

 Despite engineering control changes since our 

1998 evaluation, respirable dust exposures were 

found to be unchanged or increased 

 Bagger/cutter and dryer operators were exposed 

to the highest concentrations of respirable dust 

 Cleaning flock with compressed air, brooms, and 

shovels and manipulating bags of flock were 

observed to create airborne dust 

 Working with flock and cleaning with 

compressed air were associated with respiratory 

health effects in employees 

What Claremont Flock 

Managers Can Do 

 Provide engineering controls and improved 

material-handling work practices for the bagging 

stations, including bag filling and bag manipulation 

for weighing, sewing, and palletizing 

 Determine and control the source of elevated dust 

levels during production in the dryer rooms 

 Reposition local exhaust ventilation hoods at the 

dryer bagging stations to the tops of the bags 

being filled 

 Provide new cleaning methods to replace 

compressed-air blow-downs, sweeping, and 

shovelling of flock 

 Conduct air sampling regularly to monitor 

effectiveness of controls 

 Expand respiratory protection requirements to 

include all bagging, dryer room, and flockcleaning operations (including unplugging of 

accumulators) until these controls can be 

implemented, and ensure compliance 

 Include in the current respirator program a means 

of identifying workers with respiratory symptoms 

such as shortness of breath, wheezing, or phlegm 

production, and of detecting declines in lung 

function 

 Provide information about flock workers’ lung to 

employees and health consultants responsible for 

the respirator program 

 Continue to offer a smoking cessation program 

and to enforce the no-smoking policy already in 

place 

What Employees Can Do 

 Wear respirators when required 

 Handle bags of flock carefully to prevent airborne 

flock 

 Seek medical evaluation for respiratory 

symptoms, such as shortness of breath, wheezing, 

or phlegm production and inform the physician of 

flock exposures 

 Inform management of respiratory symptoms and 

associated flock exposures 

What To Do For More Information:

We encourage you to read the full report. If you 

would like a copy, either ask your health and safety 

representative to make you a copy or call 

1-513-841-4252 and ask for 

HETA Report #2004-0186-3011
iv 

Health Hazard Evaluation Report 2004-0186-3011 

Claremont Flock Corporation 

Leominster, Massachusetts 

August 2006 

Vinicius Antao, MD, MSc, PhD 

Chris Piacitelli, CIH 

SUMMARY

In 1997, a case of flock workers’ lung occurred at Claremont Flock Corporation. The National Institute 

for Occupational Safety and Health (NIOSH) conducted a health hazard evaluation (HHE) in 1998 at 

several of Claremont Flock’s plants and found that cleaning with compressed air and bagging flock were 

associated with worker-reported symptoms. The HHE report provided environmental and medical 

recommendations to the company to prevent flock-related disease in their plants. In March 2004, based on 

a case report consistent with flock workers’ lung at Claremont Flock’s only remaining plant, the 

Massachusetts Department of Public Health Occupational Health Surveillance Program requested 

technical assistance to determine if there had been improvement in the environmental conditions and to 

update the health status of the workforce. 

NIOSH conducted environmental and medical surveys at this plant in January 2005 to characterize 

exposures and symptoms of flock-exposed workers and internal comparison groups. The environmental 

survey consisted of personal time-integrated gravimetric sampling for respirable dust concentration and 

sampling with aerosol photometers to obtain real-time continuous relative levels of dust (approximately 

respirable) during some plant activities. Videotaping was done to record events that might be associated 

with any observed peaks in real-time readings. We invited all 80 employees to take part in the medical 

survey. Trained NIOSH interviewers administered computer-based questionnaires that focused on 

respiratory and systemic symptoms, physician diagnosis of respiratory illnesses, smoking, work history, 

respirator use, and whether fit-testing had been conducted. 

Time-integrated respirable dust sampling results showed that the bagger/cutters and the dryer operators 

had the highest geometric mean 8-hour time-weighted exposures of 0.13 and 0.80 mg/m3

, respectively. 

For most groups of workers, the exposures were found to be largely unchanged since our previous 

investigation in 1998, but for these 2 groups of workers the exposures were found to have increased. This 

happened despite the engineering control changes made in the plant since 1998. Real-time personal 

sampling results indicated that cleaning operations, such as blowing with compressed air, sweeping, and 

shovelling of flock, were associated with increases in dust levels around the workers. Manipulation of 

bags of flock both inside and outside of designated “respirator-required” zones at bagging stations was 

also associated with elevated levels of dust. 

A total of 74 employees (participation rate = 92.5%) participated in the medical survey. The majority of 

employees were male (92%), white (58%), and non-smokers (76%). The mean tenure of Claremont Flock 
v 

workers was 8 years, and only 16% of workers had either changed jobs or started working at Claremont 

Flock within the last 6 months. A total of 22 participants (30%) reported cleaning with compressed air for 

at least one hour per week, and 23 participants (31%) reported working with cotton in the last 12 months. 

Except for bagging cotton, there was an increase in the percentage of employees who wear respirators 

during their activities, when we compared the 2005 and 1998 surveys. The percentage of fit-tested 

workers also increased in the 2005 survey compared to the 1998 survey. 

The most frequently reported symptoms were wheeze apart from colds, throat irritation, and sinus 

problems. The prevalences of throat irritation, usual and chronic cough, shortness of breath while walking 

up a slight hill, and wheeze apart from colds were lower among never smokers compared to current or 

former smokers. When we took into account only symptoms with onset after employment at Claremont 

Flock, chronic phlegm and shortness of breath were the most frequently reported symptoms. ”Wheeze 

apart from cold” and “pneumonia in the last year” were statistically significantly elevated when we 

compared symptom prevalences of participating workers to expected prevalences based on national data. 

In general, dryers and baggers/cutters, workers who cleaned for one hour or more per week using 

compressed air, and employees with high cumulative exposure to flock-associated dust (> 0.425 mgyear/m3

) had higher prevalences of symptoms than other workers. In multivariate models, cleaning 

equipment with compressed air was significantly associated with throat irritation. High cumulative 

exposures were significantly associated with the development of sinus irritation. A comparison of 1998 

symptom prevalences for a subgroup that participated in both the 1998 and 2005 surveys indicated that 

those who continued working had lower symptom prevalences than those who had left after 1998. This is 

a form of “healthy-worker effect”, whereby health effects of a workplace exposure are underestimated by 

looking at current workers. 

We conclude that working with flock and cleaning with compressed air are associated with health effects 

at this plant. 

We recommend that the company prevent flock-associated dust exposures: by providing engineering 

controls and improving work practices for the bagging process including not only the filling of bags at the 

bagging stations but also the subsequent manipulation of the bags for weighing, sewing, and palletizing; 

by determining and controlling the source of elevated dust levels during production in the dryer rooms 

and repositioning the dryer room bagging station local exhaust ventilation hoods to the tops of the bags 

being filled with flock; by providing new cleaning methods that will eliminate the elevated dust levels 

associated with compressed-air blow-downs, sweeping, and shovelling of flock; by verifying 

effectiveness of controls with regular air sampling; and by expanding respiratory protection requirements, 

until the controls can be implemented, to all bagging and flock-cleaning processes, including manual 

unplugging of accumulators (enclosed baghouses), and to the entire production operation in the dryer 

rooms. In terms of medical recommendations, we suggest that the company continue to offer a smoking 

cessation program and to enforce the no-smoking policy already in place; include in the current respirator 

program a means of identifying workers with respiratory symptoms such as shortness of breath, 

wheezing, or phlegm production, and a means of detecting declines in lung function; and provide 

information about flock workers’ lung to employees and health consultants responsible for the respirator 

program. 

We also recommend that employees wear respirators when required; handle bags of flock with care to 

prevent airborne flock; seek medical evaluation for respiratory symptoms, such as shortness of breath, 

wheezing, or phlegm production and inform health care providers of flock exposures; and inform 

management of respiratory symptoms and associated flock exposures. 
vi 

The Claremont Flock plant in Leominster, Massachusetts was first evaluated by NIOSH 

in 1998 as part of its initial investigation of the risk of occupational lung disease from 

exposure to flock-associated dust. In 2004, after learning that a worker at this plant had 

been recently identified as having medical findings consistent with flock workers’ lung, 

the Massachusetts Department of Public Health Occupational Health Surveillance 

Program requested NIOSH technical assistance to determine if there had been 

improvement in environmental conditions at the plant and to obtain updated information 

on the health status of the workforce. NIOSH conducted a medical and environmental 

survey at this plant in January 2005. Despite engineering control changes implemented 

after 1998, respirable dust levels were found to be unchanged or increased. Upper 

respiratory symptoms were associated with cleaning equipment with compressed air, and 

with high cumulative exposure to flock-associated dust. To minimize the risk to workers, 

management should improve work practices and increase mandatory use of respirators by 

workers while it identifies and implements additional engineering controls. 

Keywords: NAICS 325222 (Noncellulosic Organic Fiber Manufacturing), nylon, flock, interstitial lung 

disease, flock workers’ lung 
TABLE OF CONTENTS

Preface..........................................................................................................................................................ii

Acknowledgments and Availability of Report..........................................................................................ii

Highlights of the NIOSH Health Hazard Evaluation .............................................................................iii

Summary.....................................................................................................................................................iv

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

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

Plant and Process Description ..............................................................................................................1

Disease Characteristics..........................................................................................................................2

Past Flock-associated Health Effects at Claremont Flock .................................................................3

Objectives ...............................................................................................................................................3

Methods........................................................................................................................................................3

Environmental Survey...........................................................................................................................3

Time-integrated sampling................................................................................................................3

Real-time sampling...........................................................................................................................4

Medical Survey.......................................................................................................................................4

Study population...............................................................................................................................4

Questionnaire....................................................................................................................................4

Data Analysis..........................................................................................................................................4

Results ..........................................................................................................................................................5

Environmental Survey...........................................................................................................................5

Time-integrated sampling................................................................................................................5

Real-time sampling...........................................................................................................................6

Estimation of cumulative exposures ...............................................................................................6

Medical Survey.......................................................................................................................................7

Study population demographics......................................................................................................7

Work practices and respiratory protection....................................................................................7

Symptoms ..........................................................................................................................................7

Multivariate analysis........................................................................................................................8

Comparisons between 1998 and 2005 surveys ...............................................................................8

Discussion ....................................................................................................................................................8

Recommendations.....................................................................................................................................11

References..................................................................................................................................................11

Tables and Figures....................................................................................................................................14

Appendix....................................................................................................................................................32
Health Hazard Evaluation Report No. 2004-0186-3011 Page 1 

INTRODUCTION

In March 2004, the National Institute for 

Occupational Safety and Health (NIOSH) 

received a request for technical assistance from 

the Massachusetts Department of Public Health 

Occupational Health Surveillance Program. A 

physician had notified them of a recent 

suspected work-related case of 

asthma/hypersensitivity pneumonitis from the 

Claremont Flock Corporation plant in 

Leominster, Massachusetts. A prior companyrequested health hazard evaluation (HHE) in 

1998 involved a case of flock workers’ lung 

[NIOSH 2000]. The health department requester 

asked NIOSH to revisit the Leominster plant to 

determine if there had been improvement in the 

environmental conditions and to update the 

health status of the workforce. 

This request led to our site visit to Claremont 

Flock on August 30, 2004. During this walkthrough visit, we met with management, toured 

the plant, and spoke privately with many of the 

workers. After this visit and with Claremont 

Flock management concurrence, NIOSH 

planned further investigation, including an 

environmental survey and a cross-sectional 

medical symptom survey 

The environmental survey took place from 

January 17 to 21, 2005, when airborne dust 

measurements were obtained. The medical 

survey, consisting of a symptom and work 

history questionnaire, took place on January 18 

and 19, 2005. We presented our 1998 findings to 

current workers on January 19, 2005. This report 

provides the findings from the 2005 surveys at 

this plant and a comparison with the 1998 

results, and serves to close out this technical 

assistance request. 

BACKGROUND

Flock is composed of synthetic fibers of about 1 

millimeter (mm) in length, which have been cut 

from continuous filaments (“tow”) of materials 

such as nylon, rayon, polyester, acrylic, or 

polypropylene with typical diameters of 10 to 15 

micrometers (μm). These short fibers are applied 

to adhesive-coated surfaces of many materials, 

such as fabrics and paper, to create a velvet-like 

finish to a variety of products, including 

upholstery coverings, greeting cards, glove 

boxes for automobiles, etc. The only 

occupational exposure limits for the dust 

associated with flock operations are those for 

particulates not otherwise regulated (PNOR) 

which is 5 milligrams per cubic meter of air 

(mg/m3

) for respirable dust and 15 mg/m3 for 

total dust [CFR, 2005]; however, flockassociated dusts have been shown to have health 

effects below these standards [Daroowalla, 

2005]. 

Our 1998 HHE at four of Claremont Flock’s 

plants (164 employees) in Massachusetts and 

New Hampshire consisted of a symptom and 

work history questionnaire and personal and 

area air sampling. We found that cleaning with 

compressed air, bagging flock, and smoking 

were associated with symptoms and that 

respirator use was sporadic. We recommended 

the elimination of cleaning with compressed air 

and sweeping, provision of local exhaust 

ventilation for bagging and drying operations, 

and mandatory respirator use during these 

operations until the changes could be made. 

Additionally, we recommended a no-smoking 

policy, that workers be informed about flockrelated disease, and that the medical evaluations 

include a means for identifying workers with 

frequent fever, aches, or respiratory symptoms 

to determine the need for placement out of high 

exposure jobs. 

Plant and Process Description 

During the previous HHE, the Leominster plant 

had about 100 workers assigned to 2 shifts. 

Since then, plant closures have left only the 

Leominster plant operating. Some equipment 

from the closed plants was moved into this plant, 

which continues to operate with an 80-person 

workforce on two 12-hour shifts (54 on day shift 

and 26 on night shift), weekdays only. At times, 

if production is low, the plant will not operate 

the last day of the week. The plant has several 

rotary precision cutting ranges that process 

mostly nylon, but also some polyester, rayon, 
Page 2 Health Hazard Evaluation Report No. 2004-0186-3011 

and acrylic. There are two employees assigned 

to each precision cutting range; one monitors the 

cutting of the tow, the other is responsible for 

bagging the finished/dried flock, and they 

relieve each other during breaks. An offline 

range and guillotine range cut wet flock and bag 

it without drying. In the random department, 

cotton undergarment factory scraps are ground 

into fine random-length flock fibers and then 

bagged. Some flock goes through a batch dyeing 

process, followed by drying and bagging in the 

dryer department. Periodically, a cleaning 

process referred to as a “blow-down” is 

performed. In this process, workers use 

compressed-air guns to blow settled flock from 

equipment and floors. Blow-downs are 

performed at the precision ranges and dryers any 

time a color or material change occurs that 

might contaminate the next product. Thorough 

blow-downs of precision areas are done weekly, 

two ranges per week at the end of the last night 

shift of the week. Random department blowdowns are performed bimonthly at a minimum. 

Annual shutdown is during July, and blow-down 

of the entire plant is done prior to that closing. 

Some engineering control changes occurred 

between 1998 and 2005. Production cyclones at 

the cutting ranges, rather than being discharged 

from the top into the plant environment as in 

1998, were connected to enclosed baghouses 

(accumulators) which are exhausted outdoors 

and have automatic bag shake-outs. 

Accumulators also replaced open-air baghouses. 

Local exhaust ventilation through an 

accumulator was provided for all the dryer 

bagging stations and for one precision cutting 

range screen feed chute and bagging station. 

After 1998, the production cyclones that served 

these operations were changed from inside-plant 

to outdoor discharge. The company has recently 

reported that, following our 2005 survey, air has 

been re-routed so that it is first filtered through a 

newly-installed accumulator before being sent 

outdoors. 

The company implemented a comprehensive 

respiratory protection program in 2000, which 

was updated in mid-2004, establishing bagging, 

cotton grinding, and blow-downs as tasks 

requiring use of half facepiece air-purifying 

particulate respirators. The area where 

respirators are required for bagging is restricted 

to that defined by the “red zone” painted on the 

floor immediately around the bagging station 

and scale. The 2004 program update included a 

provision for disciplinary action against 

employees refusing to wear respirators and 

coincided with construction of a respirator 

cleaning room. 

Claremont Flock’s hazard communication 

program identifies flock as a hazardous 

substance in the plant and provides information 

on the hazards in employee training. The 

company developed material safety data sheets 

(MSDS) for all of their flock products. 

The company first performed air sampling in the 

facility in October 2004 when a consultant 

conducted personal fiber sampling as well as 

some real-time dust monitoring. 

Disease Characteristics 

In 1996, a group of employees from a Rhode 

Island plant that produces and applies nylon 

flock was identified as having work-related 

interstitial lung disease (ILD) [Kern 1997, Kern 

1998]. In interstitial lung disease, inflammation 

of the air sacs and tiny airways and scarring of 

the lung tissue causes the lungs to become stiff, 

small, and less effective in transferring oxygen 

from the air and carbon dioxide from the blood. 

One year earlier, Canadian scientists had 

described five cases of ILD in a flock plant 

owned by the same company [Lougheed 1995]. 

Patients with this newly recognized disease had 

breathlessness and dry cough. The symptoms 

ranged from mild to very severe, and one subject 

required prolonged mechanical ventilation in a 

hospital intensive care unit due to respiratory 

failure. The usual latency between date of hire 

and onset of symptoms was 5 to 6 years. On 

chest radiograph, the earliest recognized cases 

had abnormal opacities described as diffuse 

reticulonodular infiltrates [Lougheed 1995, Kern 

1997, Kern 1998]. Patchy areas of consolidation, 

ground-glass opacities, and micronodules were 

the main characteristics on high-resolution 

computed tomography (CT) of the chest 

[Weiland 2003]. Pulmonary function tests 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 3 

generally showed a pattern of not expanding 

normally (a restrictive pattern) and reduced gas 

transfer (low carbon monoxide diffusing 

capacity), in which oxygen does not cross the 

lung tissue into the blood stream normally. 

Some patients also had abnormal methacholine 

challenge tests, indicating very sensitive or 

“twitchy” airways, a condition called bronchial 

hyperresponsiveness. Usually months after 

leaving work, patients’ symptoms, radiographs, 

and pulmonary function tests improved, but 

typically without complete recovery. Some cases 

were treated with high doses of corticosteroids; 

some with supplementary oxygen therapy [Kern 

2000]. A unique pattern of lung damage 

(lymphocytic bronchiolitis and peribronchiolitis 

with lymphoid hyperplasia) in biopsies is visible 

with a microscope in “flock workers’ lung” 

[Eschenbacher 1999, Boag 1999]. While the 

initial case clusters and several sporadic cases of 

flock workers’ lung have been reported in the 

nylon flock industry in North America, more 

recently reported cases in Europe have been 

associated with other types of flock. A case of 

flock workers’ lung was described in a worker 

exposed to polyethylene flock in Spain [Barroso 

2002]. In Turkey, a cross-sectional study in a 

polypropylene flock plant showed a 3.6-fold 

increase in respiratory symptoms in exposed 

workers compared to unexposed controls [Atis 

2005]. In a NIOSH investigation of rayon flock 

workers, increased symptoms and mild changes 

in lung function tests occurred in flock-exposed 

workers, particularly those using compressed air 

for cleaning [NIOSH 2005]. 

Past Flock-associated Health Effects at 

Claremont Flock 

In November 1998, NIOSH conducted 

investigations at Claremont Flock plants 

consisting of a symptom and work history 

questionnaire and personal and area sampling 

for respirable dust and fiber counts. A total of 

133 (81%) of the workers participated in the 

survey. Even though the time-integrated dust 

concentrations were low (most under 0.2 

mg/m3

), blow-downs were associated with high 

exposures and respiratory symptoms in workers. 

One case of flock workers’ lung had been 

diagnosed at that time. 

In 2004 we reviewed medical records of a 

Claremont Flock employee who was diagnosed 

with occupational asthma and an interstitial 

disease consistent with flock workers’ lung in 

2003. He had cough, shortness of breath, 

wheezing, and chest tightness. A high-resolution 

computed tomography of the chest revealed 

multiple nodules bilaterally, and pulmonary 

function tests showed diminished carbon 

monoxide diffusing capacity and an abnormal 

methacholine challenge test. These findings 

support the diagnosis of flock workers’ lung and 

asthma. This case was reported to the 

Massachusetts Department of Public Health 

Occupational Health Surveillance Program and 

motivated this technical assistance request. 

Objectives 

The main objectives of this evaluation were to: 

(1) characterize worker exposures to airborne 

particulates associated with flock-production 

operations; (2) assess health effects in relation to 

exposure to these particulates, by comparison of 

health status of exposed workers to subgroups 

within the plant with different degrees of 

exposure; (3) assess health effects by 

comparison of health status of workers to 

national data; and (4) compare the results of this 

survey with those obtained from the 1998 

survey. 

METHODS

Environmental Survey 

Time-integrated sampling 

Personal sampling in all areas of the plant 

included air samples for gravimetric 

concentration of respirable dust using NIOSH 

Method 0600 [NIOSH 2003]. Air was drawn at a 

rate of 4.2 liters per minute through a 37-

millimeter diameter, 5-micrometer pore size, 

preweighed polyvinyl chloride filter in a 3-piece 

cassette mounted on a cyclone (Model GK-2.69 

Respirable/Thoracic Cyclone, BGI, Inc., 

Waltham, MA) in the personal breathing zone of 

the workers. We evaluated all distinct 

production job titles. We obtained area samples 
Page 4 Health Hazard Evaluation Report No. 2004-0186-3011 

in the office to estimate office worker exposures. 

Samples were collected for about 8 hours during 

2 day shifts and 1 night shift. On a few workers, 

task-specific partial-shift exposures were 

measured by replacing the sampling media when 

the worker switched from operating a machine 

to cleaning tasks or between cleaning with and 

without compressed air. 

Real-time sampling 

We used aerosol photometers (light-scattering 

aerosol monitors) to obtain real-time continuous 

relative levels of dust (approximately respirable 

– instrument optimized for detection of particles 

up to 10μm) during some plant activities, 

including cleaning. The device (Model pDR1000 personalDataRAM, MIE, Inc., Bedford, 

MA) was strapped to the chest of the worker 

while performing the tasks. To record events 

that might be associated with any observed 

peaks in real-time readings, we utilized video 

cameras during the measurements. 

Medical Survey 

Study population 

Company records were provided to NIOSH 

regarding job and work area of all employees as 

of January 2005. The study population for the 

cross-sectional medical survey consisted of all 

80 employees who worked on either of the two 

12-hour shifts. 

Questionnaire 

After obtaining written informed consent, 

trained NIOSH interviewers administered a 

computer-based questionnaire to each 

participant. It included sections on upper and 

lower respiratory symptoms, systemic 

symptoms, physician diagnosis of respiratory 

illnesses, smoking and work history, respirator 

use, and whether respirator fit-testing had been 

conducted (see Appendix). Questions about 

lower respiratory symptoms were taken from 

standard, validated questionnaires [Ferris 1978, 

NCHS 1994]. Questions on onset dates and 

work-related patterns were included for the 

respiratory, nasal, and sinus symptoms. 

Data Analysis 

To assess whether Claremont Flock employees 

had excess symptoms, we compared participant 

results to national data from the Third National 

Health and Nutrition Examination Survey 

(NHANES III). We calculated ratios of the 

observed number of cases among employees to 

the expected number of cases for four symptoms 

and three medically diagnosed conditions. We 

used indirect standardization for gender, race, 

age, and smoking status [NCHS, 1996]. 

The questionnaire information was collected 

electronically and entered into a database. 

Statistical analyses of the questionnaire data and 

the environmental sampling data were conducted 

using SAS software [SAS, 2004]. The 

significance of any associations was reported as 

probability (p) values. Values less than 0.05 

were considered to represent an association not 

likely to be due purely to chance. Covariates for 

the logistic models on health outcomes included 

race, tenure, age, and smoking, the last factor 

being represented by the estimated pack-years 

(i.e., years-smoked × cigarettes-per-day/20). 

Because of the small number of female workers, 

gender was not included. An important 

limitation for the logistic models was the small 

number of positive responses for the outcomes. 

The work of Peduzzi et al. [1996] suggests that a 

stable estimate (e.g., an estimate which would 

not be expected to differ substantially with 

additional sampling) can be obtained by having 

10 cases per variable, although some authors, 

such as Stokes et al. [1995], suggest a general 

rule of five observations per variable for valid 

estimation. Therefore, we attempted to limit the 

number of variables in the logistic models by 

first fitting the ‘covariates only’ model, and then 

adding the predictor of interest. For the logistic 

models, the goodness-of-fit was assessed using 

the statistic from Hosmer and Lemeshow [2000]. 

An essential assumption for the modeling results 

was that there were no important but 

unmeasured covariates [Rosenbaum, 2002]. 

To estimate cumulative exposures, we first 

conducted an analysis of means for the various 

job categories and the 1998 and 2005 surveys. 

We also assumed that any changes in exposure 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 5 

from the first to the second surveys occurred in 

January 2002, about midway between the first 

and second surveys when many process and 

engineering control changes had been made. For 

each position and worker combination we 

calculated the product of the job-tenure (in 

years) and the assigned dust concentration, and 

then summed these products for each worker to 

obtain a cumulative exposure estimate. We 

classified workers into low and high cumulative 

exposure groups using the median of these 

estimates. 

We used Chi-square tests to compare 1998 and 

2005 prevalences of symptoms and medical 

conditions. 

RESULTS

Environmental Survey 

Time-integrated sampling 

A total of 85 personal respirable dust samples 

were collected from 54 workers. Twelve of 

those samples measured task-specific partialshift concentrations. Two area samples were 

collected in the office. Eight of the personal 

samples were voided because flock had 

overloaded the cyclone sampling device. Three 

samples did not measure levels above the 

minimum detectable concentration (MDC) of 

0.01 mg/m3

, and those samples were assigned a 

value of half the MDC for calculation purposes. 

Figure 1 shows the geometric mean respirable 

dust concentrations measured during production 

(non-cleaning) activities on each person and the 

geometric means of those samples for various 

job titles collected during this evaluation and the 

1998 evaluation in this plant. The geometric 

mean concentrations during this survey for dryer 

operators (0.80 mg/m3

) and bagger/cutter 

workers (0.13 mg/m3

) were significantly higher 

(p=0.003 and 0.03, respectively) for this survey 

compared to 1998 (0.18 and 0.07 mg/m3

, 

respectively). In both surveys, these jobs were 

among the highest exposed to respirable dust. 

The geometric mean concentration for all others 

workers in the plant was 0.05 mg/m3

, while 0.01 

mg/m3

 was found in the office. There was some 

weak evidence (p=0.10) that the average 

measurements from the maintenance workers 

were lower during the 2005 survey. The cottongrinding operation was not located in this plant 

during the previous survey, so for comparison 

purposes we used the 1998 measurements from 

grinding operations at Claremont Flock’s other 

plants that have since closed. Our sampling 

revealed that dust levels were again relatively 

high, nearly 0.60 mg/m3

, in cotton-grinding 

operations. 

The three samples collected on bagger/cutter 

operators of the offline cutting machine who cut 

and bag wet flock were all about 0.23 mg/m3

, 

whereas the guillotine bagger/cutter operators, 

who also handle only wet flock, were exposed to 

0.05 mg/m3

. For bagger/cutter operators, there 

was no difference (p=0.35) in exposure between 

those who were primarily bagging flock (0.16 

mg/m3

) and those who were cutting (0.11 

mg/m3

). 

Some cleaning activities were sampled in 2005 

as shown in Figure 2. The geometric mean for 

the personal respirable dust concentrations was 

0.39 mg/m3

 for five bagger/cutter workers 

during cleaning activities lasting 1.5 to 3.5 hours 

that primarily involved blowing with 

compressed air. During the sampling time that 

three of those workers performed cleaning 

activities other than blowing, such as 

disassembling and reassembling ductwork, a 

mean of 0.29 mg/m3

 was measured. As shown in 

the figure, the geometric mean for all 

bagger/cutters during non-cleaning production 

operations was 0.13 mg/m3

. During some of the 

sampling intervals, dryer operators conducted 

cleaning activities. Although some 

measurements representing only production 

hours were collected on these workers, no 

cleaning-exclusive measurements were obtained. 

The concentrations during the shifts that dryer 

operators performed cleaning and production 

operations were higher than the geometric mean 

concentration from all dryer production-only 

shifts. 
Page 6 Health Hazard Evaluation Report No. 2004-0186-3011 

Real-time sampling 

Real-time personal airborne dust measurements 

obtained with an aerosol photometer during a 

cleaning operation are provided in Figure 3. 

Included in the figure are a line graph of the 

measurements obtained in 3-second intervals 

and bars representing the duration of activities 

during collection of the measurements, as 

obtained from the video tapes. The sample was 

collected on a worker while he cleaned a 

precision cutting range screen room, first 

removing tape used to seal ducts in the room and 

then disassembling the screen equipment. Many 

times during these tasks, the worker used 

compressed air to clean flock from the ducts and 

equipment with associated increased dust levels. 

The most notable of these increases occurred 

toward the end of the sampling period when the 

worker was blowing flock from inside the screen 

equipment. 

Figure 4 shows another cleaning operation at a 

precision cutting range. The worker started 

blowing cyclones and ducts with compressed air 

from a raised lift platform. Halfway through the 

first blow-down cycle, he cleaned the screen 

equipment, with a substantial elevation in dust 

levels. During some brief periods while blowing 

flock from the equipment, the worker was not 

visible from a distance of about 30 feet through 

the cloud of dust generated (Figure 5). Lower 

levels were measured during his subsequent 

floor sweeping; however several periods of 

elevated peak levels were recorded. The worker 

then used compressed air again to clean the floor 

around the screen area with a corresponding rise 

in dust levels. Completion of cleaning with air 

and broom and commencement of equipment 

disassembly were marked with considerable 

decrease in dust levels. Shovelling flock was 

another cleaning task associated with substantial 

peaks in dust levels, as evidenced by the 

elevated real-time personal measurements of 

Figure 6. The worker was collecting flock that 

had been blown and swept into a pile on the 

floor and dumping it into a bag. 

Another operation where real-time 

measurements were obtained on a worker was 

bagging at a precision cutting range as presented 

in Figure 7. During the sampling, the worker 

performed bagging operations in the respiratorrequired “red zone” consisting of placing bags 

on the bagging chute, kicking the bag as it was 

being loaded to settle the mass of flock, 

removing the full bag and placing it on the scale, 

and scooping flock into or out of the bag until 

the target weight was obtained. The worker then 

pulled the bag from the scale out of the red zone 

where he sewed the top, pulled it across the floor 

and tossed it onto a pallet, compressed the bags 

on the pallet by pushing down from the side of 

the pallet or by kneeling on the bags, and 

banding the full pallet of bags with wire strap. 

The time periods when the worker was inside 

the red zone are delineated on the chart. Notable 

on the chart is that many peaks occur when the 

bagging tasks are performed outside the red 

zone. The average of the measurements while in 

the red zone was 0.29 photometric units, while 

the average obtained while performing bagging 

tasks outside the red zone was 0.43 photometric 

units. Toward the end of the sampling period, 

the worker wore the sampling device while he 

went to the break room, with an apparent decline 

in the dust level. 

Estimation of cumulative exposures 

As Figure 1 shows, most geometric means for 

the various job and survey categories varied 

about an approximate value of 0.05 mg/m3

. An 

analysis of means identified those categories 

whose geometric means were statistically larger 

than 0.05 mg/m3 and were also statistically 

distinct from each other. All other categories 

(i.e., the remaining categories whose geometric 

means were statistically indistinguishable) were 

collapsed into a single ‘All Others’ category and 

their geometric means were then combined into 

a single estimate, irrespective of job title or 

survey. This resulted in the following distinct 

job/survey categories and the corresponding 

geometric mean dust concentrations which were 

assigned during the calculation of cumulative 

exposures: 

Bagger/Cutter – 2002 to 2005 

0.127 mg/m3

Dryers – Before 2002 

0.180 mg/m3
Health Hazard Evaluation Report No. 2004-0186-3011 Page 7 

Dryers – 2002 to 2005 

0.800 mg/m3

Maintenance – Before 2002 

0.170 mg/m3

Administration 

0.010 mg/m3

All Others 

0.051 mg/m3

As discussed in the Methods Section, we 

assumed that any changes in exposure from the 

first to the second surveys occurred in January 

2002, about midway between the first and 

second surveys. For example, if a worker was 

employed since January 2001 as a dryer, the first 

year of employment would be assigned the 

lower exposure of 0.180 mg/m3

 and the balance 

of the tenure assigned the higher exposure of 

0.80 mg/m3

. If a worker was a bagger/cutter, an 

exposure of 0.051 mg/m3 would be assigned for 

the years before 2002 and 0.127 mg/m3 for the 

balance. The median of the cumulative exposure 

estimates was approximately equal to 0.425 mgyears/m3

 for the 74 workers. More complicated 

definitions of cumulative exposure also 

incorporated cleaning tasks, but these definitions 

led to an identical classification of the workers 

and nearly identical results for any modeling 

(the additional effect of cleaning was 

incorporated into the cumulative exposure by 

first estimating the mean difference between 

dust concentrations for five bagger/cutter 

workers who had separate estimates for both 

cleaning and production). 

Medical Survey 

Study population demographics 

A total of 74 of the 80 invited workers 

completed the questionnaire, resulting in an 

overall participation rate of 92.5%. 

Table A shows the distributions of participating 

workers in terms of gender, race, age, smoking 

status, tenure, and shift. The majority of 

employees were male (92%), white (58%), and 

non-smokers (76%). The mean tenure of 

Claremont Flock workers was 8 years, and only 

16% of workers had either changed jobs or 

started working at Claremont Flock within the 

last 6 months. 

Work practices and respiratory protection 

Table B shows the frequency of cleaning with 

compressed air and working with cotton, by job 

group. A total of 44 participants (60%) reported 

cleaning with compressed air, and half of these 

did so for at least one hour per week. A total of 

23 participants (31%) reported working with 

cotton in the last 12 months. 

Figure 8 demonstrates respirator use for the 

2005 survey compared with the results of the 

1998 survey at Claremont Flock. Except for 

bagging cotton, there was an increase in the 

percentage of employees who wear respirators 

during their activities. The percentage of fittested workers also increased in 2005 compared 

to the 1998 survey. 

Symptoms 

The most frequently reported symptoms were 

wheeze apart from colds (24%), throat irritation 

(23%), and sinus problems (22%) (Table C). The 

prevalences of throat irritation, usual and 

chronic cough, shortness of breath while 

walking up on a slight hill, and wheeze apart 

from colds were lower among never smokers 

when compared with current or former smokers. 

When we took into account only symptoms with 

onset after employment at Claremont Flock, 

chronic phlegm (n=7) and shortness of breath 

when walking on the level (n=7) were the most 

frequently reported symptoms. “Wheeze apart 

from cold” and “pneumonia in the last year” 

were statistically significantly elevated when we 

compared symptom prevalences observed 

among participating workers to expected 

prevalences based on national population survey 

data (Table D). 

Figure 9 demonstrates that dryers and 

baggers/cutters had higher prevalences of 

symptoms than other workers, with the 

exception of nose bleeds, wheeze, wheeze 

attacks, and chest symptoms caused by specific 

materials at work. In contrast, the prevalences of 

medically diagnosed conditions such as asthma, 
Page 8 Health Hazard Evaluation Report No. 2004-0186-3011 

chronic bronchitis, hay fever, and pneumonia 

were lower among dryers and baggers/cutters. 

Workers who cleaned for one hour or more per 

week using compressed air had higher symptom 

prevalences, except for nose bleeds, shortness of 

breath, and chest symptoms caused by specific 

materials at work, but lower prevalence of 

medically diagnosed conditions (Figure 10). 

The prevalence of aches, cough, fever, phlegm, 

sinus irritation, shortness of breath, throat 

irritation, chest tightness, and wheeze was 

higher among employees with high cumulative 

exposure to flock-associated dust (> 0.425 mgyear/m3

) than other employees. Except for hay 

fever, medically diagnosed conditions also were 

more prevalent in workers in the high 

cumulative exposure category compared to 

workers with lower exposure (Figure 11). 

Multivariate analysis 

In multivariate models, cleaning equipment with 

compressed air was significantly associated with 

throat irritation (Table E). The predicted 

probabilities suggest that non-smoking workers 

who do not clean machines at least one hour per 

week have an estimated probability of 

approximately 12% of having throat irritation. 

This probability increases to over 30% for nonsmoking workers if they cleaned machines at 

least one hour per week. 

High cumulative exposures were significantly 

associated with the development of sinus 

irritation (Table E). These results indicate that 

non-white workers with the minimum 

cumulative exposure have an estimated 

probability of about 8% of having sinus 

symptoms, and this rises to about 10% for nonwhites with the median cumulative exposure, 

and to 20% for non-whites with a cumulative 

exposure of 1.475 mg-year/m3

 (the 90th

percentile). For whites, the probabilities of 

having sinus symptoms are 18% for those with 

the minimum cumulative exposure, 23% for the 

median cumulative exposure, and 39% for the 

cumulative exposure of 1.475 mg-year/m3

. 

Models using other frequently reported 

symptoms, such as wheeze or pneumonia as the 

outcome, did not produce statistically significant 

results. 

Comparisons between 1998 and 2005 

surveys 

A total of 31 employees participated in both 

surveys. Compared with the 1998 survey, more 

of these employees reported throat irritation, 

sinus symptoms, wheeze apart from colds, body 

aches, and shortness of breath when walking on 

the level in the 2005 survey (Table F). 

When we compared the answers in the 1998 

survey for current and former workers, the 34 

current workers had reported less nose bleeds, 

throat and eye irritation, sinus symptoms, 

shortness of breath, and body aches in the 1998 

survey than the 99 workers who left employment 

after 1998 (Table G). 

When we compared the answers of current 

workers hired before and after the 1998 survey, 

workers hired after the 1998 survey reported 

more symptoms in most categories, except for 

sinus symptoms, shortness of breath, and 

wheeze (Table H). 

DISCUSSION

During our environmental survey, the offline 

and guillotine cutting machines operated 

throughout the sampling periods. Except for a 

couple hours of cleaning one day, this was also 

true for all the dryer rooms. At least half of the 

precision cutting ranges were operating during 

all the sampling periods, while the remainder 

were either operating or down for maintenance 

or cleaning during some sampling times. 

Workers reported no decline in typical 

production rate during our visit. 

Despite engineering control changes that were 

installed in the plant between 1998 and 2005, we 

found personal respirable dust measurements to 

be largely unchanged for most workers and 

higher for bagger/cutter workers and dryer 

operators. In that same time, the comprehensive 

respiratory protection program that was 

established made it mandatory that respirators be 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 9 

worn by these workers when in the “red zone” 

painted on the floor around the bagging stations. 

Our real-time personal air monitoring at a 

precision range bagging station indicated that 

dust levels were not lower when the worker 

performed bagging tasks outside of the 

designated respirator-required zone. We assume 

that this might also be true in and out of red 

zones at the bagging stations of the drying 

operations. Several workers were seen at times 

still wearing their respirators when outside the 

red zones, even though not required. Mandatory 

use of respirators for all bagging-related tasks, 

regardless of the red zone demarcations, are 

necessary until improved material-handling 

work practices and/or engineering controls can 

be developed. Some possible changes would 

include provision of local exhaust ventilation for 

bagging tasks, less handling of the bags (for 

example, sewing the top while the bag is still on 

the scale), and less aggressive handling, such as 

kicking and tossing of the bags. 

The reason for the higher dust concentrations 

measured in 2005 in the dryer rooms is not 

apparent. The production process and rate are 

unchanged, open-top cyclone discharge into the 

rooms was eliminated with the provision of 

ducting to the outside, and local exhaust 

ventilation hoods are now available at every 

dryer bagging station. Given those 

circumstances, it would be expected that the 

latest measurements would have been lower than 

those obtained in 1998. The location of the 

hoods several feet above the tops of the bags 

being filled with flock makes it unlikely that 

they were effectively capturing dust, but their 

improper location should have at worst had no 

effect on dust concentrations. Notably, the 

bagging rate is typically slower in the dryer 

rooms than in the cutting operations where lower 

concentrations were measured. Determination of 

the source of the airborne dust in the dryer 

rooms is necessary so that a plan for control can 

be implemented. Until then, expansion of the 

respirator-required zone from just around the 

bagging machine to the entire dryer room would 

be prudent. 

Surprisingly, some of the highest dust 

measurements for bagger/cutters were found on 

workers handling damp flock at the offline 

cutting machine. Attention should also be given 

to locating the source of that exposure. 

As in the 1998 evaluation, dust levels were 

relatively high in cotton-grinding operations. 

This probably does not represent a health risk, 

especially given that the cotton material 

processed is a woven fabric and not raw cotton. 

We recommended discontinuing the use of 

compressed air cleaning in the 1998 evaluation 

because it was clearly associated with 

symptoms. Cleaning with compressed air is still 

utilized at this plant as it is seen as necessary to 

the production process. The other tasks involved 

in cleaning, such as sweeping, shoveling, and, at 

times, disassembly of ductwork, produced peaks 

in dust levels as well. These findings point to the 

need for alternative methods for cleaning. Until 

new methods are in place, use of the existing 

methods could be minimized, possibly by 

vacuuming as much settled flock as possible 

first. However, it is important to note that even a 

vacuum cleaning system can generate airborne 

dust if not equipped with a high efficiency 

particulate air (HEPA) filter, if the motor 

exhaust air disturbs settled dust, or if the task of 

emptying the canister is not controlled. 

Claremont Flock is collaborating with NIOSH in 

a research project to evaluate a prototype 

vacuum system as a potentially suitable cleaning 

device. 

The accumulators in the plant have automatic 

internal air-pulse shake-downs to purge them of 

collected material. Subsequent removal of the 

material from the bottom of the units is 

facilitated with screw auger chutes. Workers 

reported frequent plugging of the accumulators 

necessitating manual unplugging, which often 

included blowing with compressed air. Although 

we did not observe workers unplugging 

accumulators during our survey, workers stated 

that it is a very messy task because large 

amounts of dust get disturbed whether or not a 

blow-down is performed. Blow-downs are 

already included as respirator-required tasks, but 

use of respirators during the entire process of 

manually cleaning accumulators should be made 

mandatory in the respiratory protection program. 
Page 10 Health Hazard Evaluation Report No. 2004-0186-3011 

Although all workers required by the company’s 

respiratory protection program to wear 

respirators were seen wearing them during the 

environmental survey, compliance was high but 

not complete according to the respiratory 

symptom and work history questionnaire. 

Gravimetric respirable dust sampling, rather 

than fiber counting, was recommended in our 

previous evaluation for the characterization of 

exposures. It remains the better choice because 

of its easier use, lower cost, lower analytical 

variability, and inclusion of non-fibrous 

particulate, which may be pertinent to risk of 

adverse health outcomes [Daroowalla 2005]. 

Periodic sampling would help verify 

effectiveness of control measures. 

We found evidence of work-related health 

effects among Claremont Flock employees. 

First, there is an excess of wheezing among 

employees compared to national rates. Within 

the plant, dryer operators and baggers/cutters, 

who had the highest exposures to respirable 

dust, had increased prevalences of most 

symptoms compared to other workers. 

Employees using compressed air for cleaning, 

which is associated with high peak dust 

exposures, also had more symptoms than other 

employees. A high cumulative exposure to 

flock-associated dusts was also associated with 

high prevalences of symptoms and medically 

diagnosed conditions. In models that controlled 

for factors that may contribute to throat irritation 

and sinus symptoms, cleaning with compressed 

air and high cumulative exposures, respectively, 

remained significantly associated with these 

symptoms. 

However, the overall prevalence of symptoms 

was lower at Claremont Flock when compared 

with results of previous NIOSH investigations in 

plants where flock was produced/processed 

[Washko 2000, Daroowalla 2005]. The 

difference in prevalences may in part be 

explained by the fact that more workers are 

wearing respiratory protection currently than in 

the past. The only exception was when we 

compared the prevalence of symptoms among 

workers with high cumulative exposure (>0.4 

mg-year/m3

): current Claremont Flock workers 

had a higher prevalence of wheeze than workers 

from five flock plants in New England, 

including Claremont Flock, in 1998 [Daroowalla 

2005]. The high prevalence of wheeze suggests 

that these workers may also have some degree of 

bronchial hyperresponsiveness (twitchy airways, 

as found in asthma). Recently, we described a 

four-fold increase in the likelihood of having an 

abnormal methacholine challenge test (MCT) 

among flock workers compared to non-flock 

workers [NIOSH 2005]. Bronchial 

hyperresponsiveness has also been found in 

some patients with flock workers’ lung [Kern 

2000]. This suggests that further studies of flock 

workers with MCTs are needed to conclusively 

elucidate the connection between exposure to 

flock-associated dust and bronchial 

hyperresponsiveness. 

Another possible explanation for the generally 

lower prevalences of symptoms among current 

workers is the so-called “healthy-worker effect”. 

A healthy worker effect is commonly observed 

in occupational disease studies that include only 

workers employed at a particular point in time 

(i.e., cross-sectional studies). Workers who left 

employment after the 1998 survey had reported 

more symptoms in 1998 than those who 

remained at the plant until the 2005 survey. 

Similarly, long-term workers reported fewer 

symptoms in 2005 than short-term workers hired 

since 1998. Both of these observations support a 

healthy worker effect. 

This workplace evaluation has limitations. The 

subjective nature of the symptom reporting may 

lead to a misestimation of the actual risk of 

flock-associated dust exposures, and medical 

records were not available to validate this 

information. Also, the small sample size limited 

statistical power and prevented more 

sophisticated statistical analysis. However, the 

high participation rate and the follow-up of a 

subset of the workers over time, providing 

insight into the healthy-worker effect, constitute 

important strengths of this survey. 

In summary, continued uncontrolled exposures 

to flock-associated dust were observed at this 

plant. Despite measures taken to reduce these 

exposures, which included both engineering 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 11 

controls and personal respiratory protection, 

health hazards still exist as evidenced by the 

recent case of flock workers’ lung and the 

findings of excess symptoms associated with 

exposures. These symptoms were mainly upper 

respiratory, such as throat irritation and sinus 

problems. Further efforts are necessary to 

implement effective control measures to 

minimize the risk of lung disease and the 

respiratory problems among flock workers in 

this plant. 

RECOMMENDATIONS

We recommend the following for 

management of this workplace: 

• Provide engineering controls and improved 

work practices for the bagging process, to 

include not only the filling of bags at the 

bagging stations but also the subsequent 

manipulation of the bags for weighing, 

sewing, and palletizing. 

• Determine and control the source of 

elevated dust levels during production in 

the dryer rooms. 

• Reposition the local exhaust ventilation 

hoods at the dryer bagging stations to the 

tops of the bags being filled with flock 

• Provide new cleaning methods that will 

minimize dust levels associated with 

compressed-air blow-downs, sweeping, 

shovelling of flock, and other flockcleaning tasks. 

• Conduct air sampling on a regular basis to 

monitor effectiveness of controls 

• Until these controls can be implemented, 

expand respiratory protection requirements 

to all bagging and flock-cleaning 

processes, including manual unplugging of 

accumulators, and to the entire production 

operation in the dryer rooms. Ensure 

employees comply with requirements to 

wear respirators 

• Continue to offer a smoking cessation 

program and to enforce the no-smoking 

policy already in place 

• Include in the current respirator program a 

means of identifying workers with 

respiratory symptoms such as shortness of 

breath, wheezing, or phlegm production, 

and a means of detecting declines in lung 

function 

• Provide information about flock workers’ 

lung to employees and health consultants 

responsible for the respirator program 

We recommend the following for employees 

of this workplace: 

• Wear respirators when required 

• Handle bags of flock with care to prevent 

airborne flock 

• Seek medical evaluation for respiratory 

symptoms, such as shortness of breath, 

wheezing, or phlegm production and 

inform their health care providers of flock 

exposures 

• Inform management of respiratory 

symptoms and associated flock exposures 

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Page 14 Health Hazard Evaluation Report No. 2004-0186-3011 

TABLES AND FIGURES

Table A. Demographics of the 74 participating workers in the survey at Claremont Flock Corporation, 

2005. 

Characteristic Number or (Mean) % or [SD] 

Gender (Male) 68 92 

Race 

 White, Non-Hispanic 43 58 

 Black, Non-Hispanic 19 26 

 Asian 6 8 

 Hispanic 4 5 

 Other*

 2 3 

Age in years (Mean) [SD] (42) [11] 

Smoking status 

 Current 18 24 

 Former 23 31 

 Never 33 45 

Day shift 49 66 

Tenure in years (Mean) [SD] (8) [7] 

Changed job title or was hired in the last 6 months 12 16 

*Includes White/American Indian or Alaskan Native, Hispanic/American Indian or Alaskan Native 

Table B. Frequency of cleaning with compressed air and working with cotton, by job group, Claremont 

Flock Corporation, 2005. 

Clean with compressed 

air for ≥ 1 hr/week 

Bagged cotton in last 

Job 12 months 

Number 

of 

workers Number % Number % 

Bagger/Cutter 19 13 68 7 37 

Dryer Operator 6 6 100 5 83 

Extractor Operator 6 2 33 5 83 

Kettle Operator 7 0 - 2 29 

Cotton Grinder Operators 2 0 - 2 100 

Maintenance 4 0 - 0 - 

Material Handler 4 0 - 0 - 

Office/Administration 13 1 8 0 - 

Other (Team Leaders, Lab Workers, etc.) 13 0 - 2 15 

TOTAL 74 22 30 23 31 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 15 

Table C. Prevalence of symptoms among 74 participating workers, by smoking status, Claremont Flock 

Corporation, 2005. 

All Smoking status 

participants Current Former Never 

N=74 N=18 N=23 N=33 Symptom 

Number % Number % Number % Number % 

3 or more episodes in the last 12 months 

 Nosebleeds 7 9 1 6 3 13 3 9 

 Throat irritation 17 23 6 33 6 26 5 15 

 Eye irritation 8 11 2 11 2 9 4 12 

 Sinus symptoms 16 22 2 11 7 30 7 21 

Hay fever 9 12 3 17 1 4 5 15 

Mucous membrane irritation*

 21 28 7 39 7 30 7 21 

Usual cough 6 8 3 17 2 9 1 3 

Chronic cough 7 9 2 11 3 13 2 6 

Usual phlegm 10 14 3 17 2 9 5 15 

Chronic phlegm 7 9 1 6 2 9 4 12 

Bronchitis-like symptoms†

 5 7 1 6 1 4 3 9 

Shortness of breath on slight hill (and no 

other reason for difficulty walking) 

9 12 4 22 2 9 3 9 

Shortness of breath walking on level (and 

no other reason for difficulty walking) 

4 5 2 11 0 2 6 

Interstitial lung disease-like symptoms‡

 4 5 1 6 1 4 2 6 

Wheeze apart from colds 18 24 7 39 5 22 6 18 

Wheeze most of the time 2 3 1 6 0 1 3 

Wheeze with shortness of breath 10 14 2 11 3 13 5 15 

Asthma-like symptoms§

 12 16 3 17 3 13 6 18 

3 or more episodes in the last 12 months 

 Fever 8 11 4 22 1 4 3 9 

 Aches 11 15 2 11 3 13 6 18 

Systemic symptoms|| 17 23 5 28 4 17 8 24 

*Defined as having three or more episodes of throat or eye irritation in the last 12 months 

†

Defined as having either usual or chronic cough and either usual or chronic phlegm 

‡

Defined as having either usual or chronic cough and shortness of breath on slight hill or shortness of breath while 

walking with a person of his/her own age on the level. 

§

Defined as having wheezing most of the time or wheeze with shortness of breath. 

||Defined as having three or more episodes of fever or flu-like achiness in the last 12 months.
Page 16 Health Hazard Evaluation Report No. 2004-0186-3011 

Table D. Ratios of observed to expected number of participants with selected symptoms and medically 

diagnosed conditions Claremont Flock Corporation, 2005*. 

Symptom/Condition Observed Number Expected Number Ratio (95% C.I.) 

Chronic cough† 7 4 1.6 (0.8 – 3.3) 

Chronic phlegm‡ 7 5 1.6 (0.8 – 3.2) 

Wheeze apart from cold§

 17 7 2.6 (1.6 – 4.2) 

Shortness of breath|| 11 11 1.0 (0.6 – 1.8) 

Pneumonia¶

 3 1 3.0 (1.0 – 8.7) 

Hay fever** 8 8 1.1 (0.5 – 2.1) 

Chronic bronchitis†† 2 3 0.8 (0.2 – 2.9) 

* 67 participating workers in comparison with NHANES III data, adjusted for gender, race, age, and 

smoking categories (7 workers were excluded due to selection of multiple race categories). 

†

 Question 5c: “Do you usually cough like this on most days for three or more consecutive months during the year?” 

‡

 Question 6c: “Do you bring up phlegm like this on most days for three or more consecutive months during the 

year?” 

§ Question 7a: “Does your chest sound wheezy or whistling occasionally apart from colds?” 

|| Question 11a: “Are you troubled by shortness of breath when hurrying on level ground or walking up a slight hill?” 

¶

 Question 20a: “Have you ever been told by a doctor that you had pneumonia?” 

** Question 22a: “Have you ever been told by a doctor that you had hay fever?” 

†† Question 23a: “Have you ever been told by a doctor that you had chronic bronchitis?” 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 17 

Table E. Summary of selected results for the multivariate logistic modeling of common symptoms, 

Claremont Flock Corporation, 2005*. 

Outcome Predictor Covariate Odds Ratio 

(95% C.I.) Model Prediction & Interpretation

throat irritation cleaning† smoking 3.5 

(1.1 – 12.0) 

A 12% occurrence of throat irritation for nonsmoking workers who do not clean machines at 

least one hour per week; a 33% occurrence of 

throat irritation for non-smoking workers who 

clean machines at least one hour per week. 

sinus irritation 

Cumulative 

exposure†

(1 mg-year 

per m3

) 

race 

2.1 

(1.1 – 4.7) 

An 8% occurrence of sinus irritation for nonwhite workers with the minimum cumulative 

exposure; a 10% occurrence for non-whites with 

the median cumulative exposure, and a 20% 

occurrence for non-whites with cumulative 

exposures of 1.475 (the 90th percentile). An 

18% occurrence of sinus irritation for whites 

with the minimum cumulative exposure; a 23% 

occurrence for whites with the median 

cumulative exposure, and a 39% occurrence for 

whites with cumulative exposures of 1.475. 

*Due to the small number of cases for the various outcomes, the number of variables for the logistic 

models was restricted by first fitting the ‘covariates only’ model, which included smoking, age, tenure, 

and race. 

†

Statistically significant for α = 0.05
Page 18 Health Hazard Evaluation Report No. 2004-0186-3011 

Table F. Comparison of the 1998 and 2005 prevalences of symptoms among workers who participated in 

both the 1998 and 2005 surveys, Claremont Flock Corporation, 2005. 

1998 Survey 

N=31 

2005 Survey 

N=31 

Symptom 

Number % Number % 

3 or more episodes in the last 12 months: 

 Nosebleeds 

 Throat irritation 

 Eye irritation 

 Sinus symptoms 

Hay fever 

Mucous membrane irritation*

2 

5 

3 

7 

4 

7 

6 

10 

16 

23 

13 

23 

2 

6 

1 

9 

3 

7 

6 

19 

3 

29 

10 

23 

Usual cough 

Chronic cough 

Usual phlegm 

Chronic phlegm 

Bronchitis-like symptoms†

Shortness of breath on slight hill (and no other 

reason for difficulty walking) 

Shortness of breath walking on level (and no other 

reason for difficulty walking) 

Interstitial lung disease-like symptoms‡

5 

7 

6 

7 

5 

6 

0 

3 

16 

23 

19 

23 

16 

19 

0 

10 

2 

3 

3 

3 

2 

3 

3 

1 

6 

10 

10 

10 

6 

10 

10 

3 

Wheeze apart from colds 

Wheeze most of the time 

Wheeze with shortness of breath 

Asthma-like symptoms§

6 

0 

8 

8 

19 

0 

26 

26 

10 

1 

4 

5 

32 

3 

13 

16 

3 or more episodes in the last 12 months: 

 Fever 

 Aches 

Systemic symptoms||

2 

2 

3 

6 

6 

10 

3 

4 

6 

10 

13 

19 

*Defined as having three or more episodes of throat or eye irritation in the last 12 months 

†

Defined as having either usual or chronic cough and either usual or chronic phlegm 

‡

Defined as having either usual or chronic cough and shortness of breath on slight hill or shortness of breath while 

walking with a person of his/her own age on the level. 

§

Defined as having wheezing most of the time or wheeze with shortness of breath. 

||Defined as having three or more episodes of fever or flu-like achiness in the last 12 months.
Health Hazard Evaluation Report No. 2004-0186-3011 Page 19 

Table G. Comparison of prevalences of symptoms in 1998 survey among current and former employees 

as of January 2005, Claremont Flock Corporation. 

Current employee 

N=34 

Former employee 

N=99 

Symptom 

Number % Number % 

3 or more episodes in the last 12 months: 

 Nosebleeds 

 Throat irritation 

 Eye irritation 

 Sinus symptoms 

Hay fever 

Mucous membrane irritation*

2 

5 

3 

7 

4 

7 

6 

15 

9 

21 

12 

21 

10 

30 

18 

32 

14 

41 

10 

30 

18 

32 

14 

41 

Usual cough 

Chronic cough 

Usual phlegm 

Chronic phlegm 

Bronchitis-like symptoms†

Shortness of breath on slight hill (and no other 

reason for difficulty walking) 

Shortness of breath walking on level (and no other 

reason for difficulty walking) 

Interstitial lung disease-like symptoms‡

6 

7 

7 

8 

6 

6 

0 

3 

18 

21 

21 

24 

18 

18 

0 

9 

14 

15 

17 

19 

13 

19 

3 

8 

14 

15 

17 

19 

13 

19 

3 

8 

Wheeze apart from colds 

Wheeze most of the time 

Wheeze with shortness of breath 

Asthma-like symptoms§

6 

0 

8 

8 

18 

0 

24 

24 

19 

2 

13 

14 

19 

2 

13 

14 

3 or more episodes in the last 12 months: 

 Fever 

 Aches 

Systemic symptoms||

2 

2 

3 

6 

6 

9 

6 

14 

15 

6 

14 

15 

*Defined as having three or more episodes of throat or eye irritation in the last 12 months 

†

Defined as having either usual or chronic cough and either usual or chronic phlegm 

‡

Defined as having either usual or chronic cough and shortness of breath on slight hill or shortness of breath while 

walking with a person of his/her own age on the level. 

§

Defined as having wheezing most of the time or wheeze with shortness of breath. 

||Defined as having three or more episodes of fever or flu-like achiness in the last 12 months.
Page 20 Health Hazard Evaluation Report No. 2004-0186-3011 

Table H. Comparison of prevalences of symptoms by hire date, Claremont Flock Corporation, 2005. 

Hired prior to 

11/1998 

N=39 

Hired after 11/1998 

N=35 

Symptom 

Number % Number % 

3 or more episodes in the last 12 months: 

 Nosebleeds 

 Throat irritation 

 Eye irritation 

 Sinus symptoms 

Hay fever 

Mucous membrane irritation*

3 

7 

2 

9 

6 

8 

8 

18 

5 

23 

15 

21 

4 

10 

6 

7 

3 

13 

11 

29 

17 

20 

9 

37 

Usual cough 

Chronic cough 

Usual phlegm 

Chronic phlegm 

Bronchitis-like symptoms†

Shortness of breath on slight hill (and no other 

reason for difficulty walking) 

Shortness of breath walking on level (and no other 

reason for difficulty walking) 

Interstitial lung disease-like symptoms‡

2 

3 

3 

3 

2 

3 

3 

1 

5 

8 

8 

8 

5 

8 

8 

3 

4 

4 

7 

4 

3 

6 

1 

3 

11 

11 

20 

11 

9 

17 

3 

9 

Wheeze apart from colds 

Wheeze most of the time 

Wheeze with shortness of breath 

Asthma-like symptoms§

10 

1 

4 

5 

26 

3 

10 

13 

8 

1 

6 

7 

23 

3 

17 

20 

3 or more episodes in the last 12 months: 

 Fever 

 Aches 

Systemic symptoms||

4 

4 

7 

10 

10 

18 

4 

7 

10 

11 

20 

19 

*Defined as having three or more episodes of throat or eye irritation in the last 12 months 

†

Defined as having either usual or chronic cough and either usual or chronic phlegm 

‡

Defined as having either usual or chronic cough and shortness of breath on slight hill or shortness of breath while 

walking with a person of his/her own age on the level. 

§

Defined as having wheezing most of the time or wheeze with shortness of breath. 

||Defined as having three or more episodes of fever or flu-like achiness in the last 12 months.
Health Hazard Evaluation Report No. 2004-0186-3011 Page 21 

 

Figure 1. Job geometric means (plotting symbol = •) and individual worker geometric means (plotting 

symbol = +) for 8-hour personal respirable dust concentrations during production operations (cleaning tasks 

excluded) for the 1998 and 2005 surveys at the Leominster plant, Claremont Flock Corporation. Only area 

samples were collected from the offices. The cotton data from 1998 were obtained only from other 

Claremont Flock plants. 

* P-value = 0.03 for comparison of 1998 and 2005 means. 

† P-value = 0.003 for comparison of 1998 and 2005 means. 

‡ P-value = 0.10 for comparison of 1998 and 2005 means.
Page 22 Health Hazard Evaluation Report No. 2004-0186-3011 

Figure 2. Personal respirable dust concentrations for production and cleaning tasks for five bagger/cutter 

workers (identified as A – E) and two dryer workers (F – G), Claremont Flock Corporation, 2005. The 

solid vertical lines represent the job geometric mean levels for all production samples (i.e., the same 

geometric means displayed for the bagging/cutting and drying jobs in Figure 1). 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 23 

0

1

2

3

4

5

6

7

8

9

10

time 10:10 10:20 10:30 10:40 10:50 11:00 11:10 11:20 11:30 11:40 11:50 Dust Level (photometric units*)

peak = 23.0 peaks up to 15.6

blow

shaking and 

removing 

portion of 

ductwork

deepest valleys after 11:20 

associated with worker being 

outside the screen room

disassembling screen removing tape from ducts

* Photometric units are the approximation of respirable dust concentration provided by the aerosol photometer

Event Duration Bars

Concentration Curve

blow blow blow blow blow blow blow blow blow

Figure 3. Real-time personal airborne dust measurements during cleaning of precision cutting range 

screen room, Claremont Flock Corporation, 2005. 
Page 24 Health Hazard Evaluation Report No. 2004-0186-3011 

0

2

4

6

8

10

12

14

16

18

20

time 8:40 8:50 9:00 9:10 9:20 9:30 9:40 9:50 10:00 Dust Level (photometric units*)

Concentration Curve

Event Duration 

blowing

* Photometric units are the approximation of respirable dust concentration provided by the aerosol photometer

blowing

sweeping disassembling

equipment

peaks up to 54.7 peaks up to 45.6 

Figure 4: Real-time personal airborne dust measurements during cleaning of precision cutting range, 

Claremont Flock Corporation, 2005. 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 25 

Figure 5: Precision cutting room during blow-down cleaning with compressed air, Claremont Flock 

Corporation, 2005. 
Page 26 Health Hazard Evaluation Report No. 2004-0186-3011 

0

2

4

6

8

10

12

14

16

18

20

time 9:25 9:35 9:45 9:55 Dust Level (photometric units*)

Concentration Curve

Event Duration Bars

break

* Photometric units are the approximation of respirable dust concentration provided by the aerosol photometer

shovelling flock

other worker blowing 

with compressed air 

disassembling pipes from lift

loading pallet

in room

 (out of video)

peaks up to 77.4 rolling pallet 

out of room

Figure 6: Real-time personal airborne dust measurements during cleaning of precision cutting range, 

Claremont Flock Corporation, 2005. 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 27 

0

0.5

1

1.5

2

time 14:17 14:27 14:37 14:47 14:57 Dust Level (photometric units*)

Concentration Curve

Event Duration Bars

bagging break

* Photometric units are the approximation of respirable dust concentration provided by the aerosol photometer

Red = time periods when worker is performing tasks while in the respirator-required "red" zone marked with floor paint

peaks up to 15.0 

Red Red Red Red Red Red Red Red Red Red Red

Figure 7. Real-time personal airborne dust measurements during bagging at a precision cutting range, 

Claremont Flock Corporation, 2005. 
Page 28 Health Hazard Evaluation Report No. 2004-0186-3011 

Figure 8. Percentage of employees that reported using respirator in the 1998 and 2005 surveys, by activity 

and fit-testing status, Claremont Flock Corporation. 

* 1998 survey question: “Do you wear a mask or respirator when conducting a blowdown?” 

 2005 survey question: “Do you wear a mask or respirator when cleaning equipment with compressed air?” 

†

 Question not asked in the 1998 survey. 

Cleaning with compressed air* 

Bagging flock 

Bagging cotton 

Other activities†

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

2005 (n = 24)

1998 (n = 0)

2005 (n = 17)

1998 (n = 29)

2005 (n = 36)

1998 (n = 35)

2005 (n = 39)

1998 (n = 38)

Fit-tested Non fit-tested
Health Hazard Evaluation Report No. 2004-0186-3011 Page 29 

Figure 9. Prevalence of symptoms and physician-diagnosed conditions defined by type of job, Claremont Flock Corporation, 20

18%

10%

12%

29%

4%

16%

12%

10%

16%

25%

16%

10%

12%

22%

18%

10%

8%

0%

13%

22%

9%

0%0%

9%

13%

9%

22%

17%

22%

17%

22%

35%

9%

17%

0% 5% 10% 15% 20% 25% 30% 35% 40% 

Hay Fever (Q22a)

Fever (Q14a)

Aches (Q15a)

Pneumonia (Q20a)

Chronic Bronchitis (Q23a)

Asthma (Q21a)

Chest Symptoms from Work (Q37a)

Chest Tightness (Q12a)

Wheeze Attack (Q9a)

Wheeze (Q7a)

Shortness of Breath (Q11a)

Phlegm (Q6a)

Cough (Q5a)

Sinus Irritation (Q19a)

Throat Irritation (Q17a)

Nose Bleeds (Q16a)

Eye Irritation (Q18a)*

Prevalence (%)

Dryers or BOther work

*The questions from the questionnaire (see Appendix), used to define each symptom, appear in parentheses† Chi-square statistically significant at α = 0.05.

†
Page 30 Health Hazard Evaluation Report No. 2004-0186-3011 

Figure 10. Prevalence of symptoms and physician-diagnosed conditions defined by cleaning status, Claremont Flock Corporati

17%

8%

13%

29%

4%

13%

12%

10%

13%

23%

17%

10%

13%

21%

17%

12%

10%

0%

18%18%

9%

0%

5%

9%

14%14%

27%

14%

23%

14%

23%

5%

14%

0% 5% 10% 15% 20% 25% 30% 35

Hay Fever (Q22a)

Fever (Q14a)

Aches (Q15a)

Pneumonia (Q20a)

Chronic Bronchitis (Q23a)

Asthma (Q21a)

Chest Symptoms from Work (Q37a)

Chest Tightness (Q12a)

Wheeze Attack (Q9a)

Wheeze (Q7a)

Shortness of Breath (Q11a)

Phlegm (Q6a)

Cough (Q5a)

Sinus Irritation (Q19a)

Throat Irritation (Q17a)

Nose Bleeds (Q16a)

Eye Irritation (Q18a)*

Prevalence (%)

CleaClea

†

*The questions from the questionnaire (see Appendix), used to define each symptom, appear in parentheses† Chi-square statistically significant at α = 0.05.
Health Hazard Evaluation Report No. 2004-0186-3011 Page 31 

Figure 11. Prevalence of symptoms and physician-diagnosed condition by cumulative exposure, Claremont Flock Corporation, 

19%

5%

11%11%

0%

5%

11%

5%

19%

16%

14%

11%11%

14%

19%

11%

16%

5%

16%

19%

35%

5%

16%

11%

16%

8%

32%

19%

16%16%

30%

27%

8%

5%

0% 5% 10% 15% 20% 25% 30% 35% 40% 

Hay Fever (Q22a)

Fever (Q14a)

Aches (Q15a)

Pneumonia (Q20a)

Chronic Bronchitis (Q23a)

Asthma (Q21a)

Chest Symptoms from Work (Q37a)

Chest Tightness (Q12a)

Wheeze Attack (Q9a)

Wheeze (Q7a)

Shortness of Breath (Q11a)

Phlegm (Q6a)

Cough (Q5a)

Sinus Irritation (Q19a)

Throat Irritation (Q17a)

Nose Bleeds (Q16a)

Eye Irritation (Q18a)*

Prevalence (%)

*The questions from the questionnaire (see Appendix), used to define each symptom, appear in parentheses† Chi-square statistically significant at α = 0.05.

†
Page 32 Health Hazard Evaluation Report No. 2004-0186-3011 

APPENDIX

 QUESTIONNAIRE 

ID Number: _________ 

HETA 2004 – 0186 

Interviewer: ____________ Interview Date: __ __ / __ __ / __ __ __ __ 

 (Month) (Day) (Year) 

Section I: Identification and Demographic Information 

Name: ____________________________ ______________________ ____ 

 (Last name) (First name) (MI) 

Address:_______________________________________________________ 

(Number, Street, and/or Rural Route) 

 _____________________ ______________ __________ 

 (City) (State) (Zip Code) 

Home Telephone Number: ( ) _______ - __________ 

If you were to move, is there someone who would know how to contact you? 

Name: ____________________________ ______________________ ____ 

 (Last name) (First name) (MI) 

Relationship to you:____________________ 

Address:_______________________________________________________ 

 (Number, Street, and/or Rural Route) 

 _____________________ ______________ __________ 

(City) (State) (Zip Code) 

Home Telephone Number: ( ) _______ - __________ 

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 

1. Date of Birth: __ __ / __ __ / __ __ __ __ 

 (Month) (Day) (Year) 

2. Sex: 1. ____ Male 2. ____ Female 

3. Are you Spanish, Hispanic, or Latino? 1. ____Yes 0.____No. 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 33 

4. Select one or more of the following categories to describe your race: 

 1. ___ White 

 2. ___ African-American or Black 

 3. ___ Asian 

 4. ___ American Indian or Alaska Native 

 5. ___ Native Hawaiian or Other Pacific Islander 

Section II: Health Information 

I’m going to ask you some questions about your health. The answer to many of these questions will be “Yes” or 

“No.” If you are in doubt about whether to answer “Yes” or “No,” then please answer “No.” 

COUGH 

5a. Do you usually have a cough? (This includes a cough with 1. ___ Yes 0. ___ No 

 first smoke or on first going out-of-doors, but does not include 

 clearing of throat.) 

 IF YES: 

 5b. Do you usually cough as much as 4 to 6 times a day. 1. ___ Yes 0. ___ No 

 

 for 4 or more days out of the week? 

 5c. Do you usually cough like this on most days for 1. ___ Yes 0. ___ No 

 3 or more consecutive months during the year? 

 5d. In what year did you first notice this cough? __ __ __ __ 

PHLEGM 

6a. Do you usually bring up phlegm from your chest? (This includes 1. ___ Yes 0. ___ No 

 phlegm with a first smoke, on first going out-of-doors, and 

 swallowed phlegm; but does not count phlegm from the nose.) 

 IF YES: 

6b. Do you usually bring up phlegm like this as much 1. ___ Yes 0. ___ No 

 as twice a day, 4 or more days out the week? 

6c. Do you bring up phlegm like this on most days for 1. ___ Yes 0. ___ No 

 3 or more consecutive months during the year? 

6d. In what year did you first notice this phlegm? __ __ __ __ 
Page 34 Health Hazard Evaluation Report No. 2004-0186-3011 

WHEEZING 

7a. Does your chest sound wheezy or whistling 1. ___ Yes 0. ___ No 

 occasionally apart from colds? 

 IF YES: 

 7b In what year did you start wheezing like this? __ __ __ __ 

. 

8a. Does your chest sound wheezy or whistling most of the time? 1. ___ Yes 0. ___ No 

IF YES: 

8b In what year did you start wheezing like this? __ __ __ __ 

. 

ATTACKS OF WHEEZING 

9a. Have you ever had an attack of wheezing that has made you feel 1. ___ Yes 0. ___ No 

 short of breath? 

 IF YES: 

9b. In what year did you first have an attack of 

 wheezing with shortness of breath? __ __ __ __ 

 

9c. Have you ever required medicine or treatment for 1. ___ Yes 0. ___ No 

 the(se) attack(s)? 

BREATHLESSNESS 

10a. Do you have any nerve, muscle, bone problems or heart trouble 1. ___ Yes 0. ___ No 

 that makes walking difficult for you? 

 IF YES, ask for description of difficulty:

10b.______________________________________________________________________________ 

11a. Are you troubled by shortness of breath when hurrying on level 1. ___ Yes 0. ___ No 

 ground or walking up a slight hill? 

 IF YES: 

11b. Do you have to walk slower than people of your own 1. ___ Yes 0. ___ No 

 age on the level because of shortness of breath? 

11c. In what year did you first notice this shortness of breath? __ __ __ __ 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 35 

CHEST TIGHTNESS 

12a. Have you ever woken up with a feeling of tightness in your chest? 1. ___ Yes 0. ___ No 

 IF YES: 

12b. During the last 12 months, have you woken up with a 1. ___ Yes 0. ___ No 

 feeling of chest tightness? 

13a. Have you ever had to change your job, job duties, or work area 1. ___ Yes 0. ___ No 

 at this plant because of breathing difficulties? 

 IF YES: 

13b. What month and year did you change your job, job duties, or __ __ / __ __ __ __ 

 work area? (Month) (Year) 

 

13c. Describe your job, job duties, and/or work area before the change: 

 ________________________________________________________________________________ 

13d. Describe your job, job duties, and/or work area after the change: 

________________________________________________________________________________

13e. Were your breathing problems after the change: 1. ___ Better 

 2. ___ The Same 

 3. ___ Worse 

SYSTEMIC SYMPTOMS 

FEVER 

14a. In the last 12 months, have you had 3 or more episodes, 1. ___ Yes 0. ___ No 

 of fever? 

IF YES:

 14b. In what year did you first notice fevers like this? __ __ __ __ 

 (Year) 

 14c. When do you usually get these episodes of fever? 1.__ Usually on workdays 

 2.__ Usually on days off work 

 3.__ No noticeable pattern 

 4.__ Don't know 

ACHES

15a. In the last 12 months, have you had 3 or more episodes of 1. ___ Yes 0. ___ No

 flu-like achiness or aches all over your body? 
Page 36 Health Hazard Evaluation Report No. 2004-0186-3011 

IF YES: 

 15b. In what year did you first notice aches like this? __ __ __ __ 

 (Year) 

 15c. When do you usually get these aches? 1.__ Usually on workdays 

 2.__ Usually on days off work 

 3.__ No noticeable pattern 

 4.__ Don't know 

D. IRRITANT SYMPTOMS 

NOSE 

16a. In the last 12 months, have you had 3 or more nosebleeds? 1. ___ Yes 0. ___ No

IF YES: 

 16b. In what year did you first notice these nosebleeds? __ __ __ __ 

 (Year) 

 16c. When do you usually have these nosebleeds? 1.__ Usually on workdays 

 2.__ Usually on days off work 

 3.__ No noticeable pattern 

 4.__ Don't know 

THROAT 

17a. In the last 12 months, have you had 3 or more episodes 1. ___ Yes 0. ___ No

 of throat irritation, soreness, or tickle? 

IF YES: 

 17b. In what year did you first notice throat __ __ __ __ 

 irritations like this? (Year) 

 17c. When do you usually have this throat irritation? 1.__ Usually on workdays 

 2.__ Usually on days off work 

 3.__ No noticeable pattern 

 4.__ Don't know 

EYES 

18a. In the last 12 months, have you had 3 or more episodes 1. ___ Yes 0. ___ No 

 of eye irritation? 

IF YES: 

 18b. In what year did you first notice these episodes __ __ __ __ 

 of eye irritation? (Year) 

 18c. When do you usually have this eye irritation? 1.__ Usually on workdays 

 2.__ Usually on days off work 

 3.__ No noticeable pattern 

 4.__ Don't know 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 37 

SINUS 

19a. In the last 12 months, have you had 3 or more episodes of 1. ___ Yes 0. ___ No 

 sinus fullness, drainage, or sinus pain? 

IF YES: 

 19b. In what year did you first notice these __ __ __ __ 

 sinus symptoms? (Year) 

 19c. When do these sinus symptoms usually occur? 1.__ Usually on workdays 

 2.__ Usually on days off work 

 3.__ No noticeable pattern 

 4.__ Don't know 

RESPIRATORY ILLNESSES 

PNEUMONIA 

20a. Have you ever been told by a doctor that you had pneumonia? 1. ___ Yes 0. ___ No 

IF YES:

 20b. In what year did you last have pneumonia? __ __ __ __

 (Year) 

 20c. How many episodes of pneumonia have you had ______ episodes 

 in the last year? 

ASTHMA 

21a. Has a doctor ever told you that you have asthma? 1. ___ Yes 0. ___ No 

IF YES:

 21b. At what age were you first told that you had asthma? __ __ (Age in years)

 21c. Do you still have asthma? 1. ___ Yes 0. ___ No 

 IF NO: 

 18d. At what age did your asthma stop? __ __ (Age in years)

HAY FEVER 

22a. Has a doctor ever told you that you have hay fever? 1. ___ Yes 0. ___ No

IF YES:

 22b. At what age were you first told you had hay fever? __ __ (Age in years) 

 22c. Do you still have symptoms of hay fever? 1. ___ Yes 0. ___ No
Page 38 Health Hazard Evaluation Report No. 2004-0186-3011 

IF NO: 

22d. At what age did you stop having hay fever symptoms? __ __ (Age in years)

CHRONIC BRONCHITIS

23a. Has a doctor ever told you that you had chronic bronchitis? 1. ___ Yes 0. ___ No

IF YES:

 23b. At what age were you first told you had chronic bronchitis? __ __ (Age in years) 

 23c. Do you still have symptoms of chronic bronchitis? 1. ___ Yes 0. ___ No

IF NO:

23d. At what age did you stop having chronic bronchitis symptoms? __ __ (Age in years) 

Section III: Work History at Claremont Flock Co.

I am now going to ask you questions about your current job at Claremont Flock. 

24. What is your current department? ________________________________ 

25. What is your current job title? ________________________________ 

26. What shift do you usually work? 1. ___ Day 

 2. ___ Night 

3 ___ Rotate shifts 

27. During an average week, how many hours do you usually work? ______ Hours per week 

28. During an average week, how many days do you usually work? ______ Days per week 

29a. Do you ever work in an area where flock is processed? 1. ___ Yes 0. ___ No 

IF YES: 

29b. During an average week, how many hours do you work ______ Hours per week 

 in areas where flock is processed? 

30a. Do you ever clean equipment with compressed air (blowdowns)? 1. ___ Yes 0. ___ No 

IF YES: 

30b. During an average week, how many times do you clean ______ Times per week 

 equipment with compressed air? 

30c. During an average cleaning session, how long do you spend ______ Minutes 

 cleaning equipment with compressed air (in minutes)? Per cleaning session 

 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 39 

30d. Do you wear a mask or respirator when cleaning 1. ___ Yes 0. ___ No 

 equipment with compressed air? 

 IF YES: 

 30e. Do you wear a mask or respirator: 1. ___ During all cleanings? 

 2. ___ During most cleanings? 

3. ___ During some cleanings? 

 

 30f. Which type of mask or respirator do you wear? (See Diagram) 1. ___ Single strap 

 2. ___ 2-strap 

3. ___ Half face piece 

4. ___ Full face piece 

5. ___ PAPR 

6. ___ SCBA 

7. ___ Other 

Describe:_______________________ 

30g. Were you fit tested for this respirator? 1. ___ Yes 0. ___ No

31a. During an average week, how many times is equipment cleaned 

with compressed air near your work area that you don’t directly conduct? ______ Times per week 

 

IF NOT = 0:

31b. Do you wear a mask or respirator when cleanings 1. ___ Yes 0. ___ No 

 of equipment with compressed air are occurring? 

IF YES: 

 31c. Do you wear a mask or respirator: 1. ___ During all cleanings? 

 2. ___ During most cleanings? 

3. ___ During some cleanings? 

 

 31d. Which type of mask or respirator do you wear? (See Diagram) 1. ___ Single strap 

 2. ___ 2-strap 

3. ___ Half face piece 

4. ___ Full face piece 

5. ___ PAPR 

6. ___ SCBA 

7. ___ Other

Describe:_______________________

 

 31e. Were you fit tested for this respirator? 1. ___ Yes 0. ___ No

BAGGING FLOCK 

32a. In the last 12 months, have you spent any time 1. ___ Yes 0. ___ No 

 bagging flock (not cotton flock)?
Page 40 Health Hazard Evaluation Report No. 2004-0186-3011 

IF YES: 

32b. In an average shift, how many hours do you spend bagging flock? ___ ___ hours in a shift 

 

32c. Do you wear a mask or respirator while you are bagging flock? 1. ___ Yes 0. ___ No 

 

 IF YES: 

 32d. Do you wear a mask or respirator: 1. ___ During all bagging? 

 2. ___ During most bagging? 

3. ___ During some bagging? 

 

 32e. Which type of mask or respirator do you wear? (See Diagram) 1. ___ Single strap 

 2. ___ 2-strap 

3. ___ Half face piece 

4. ___ Full face piece 

5. ___ PAPR 

6. ___ SCBA 

7. ___ Other 

 Describe:_______________________ 

 

 32f. Were you fit tested for this respirator? 1. ___ Yes 0. ___ No 

BAGGING COTTON 

33a. In the last 12 months, have you spent any time bagging cotton? 1. ___ Yes 0. ___ No 

IF YES:

33b. In an average shift, how many hours do you spend bagging cotton __ __ hours in a shift 

33c. Do you wear a mask or respirator while you are bagging cotton? 1. ___ Yes 0. ___ No 

 

 

 IF YES: 

 33d. Do you wear a mask or respirator: 1. ___ During all bagging? 

 2. ___ During most bagging? 

3. ___ During some bagging? 

 

 33e. Which type of mask or respirator do you wear? (See Diagram) 1. ___ Single strap 

 2. ___ 2-strap 

3. ___ Half face piece 

4. ___ Full face piece 

5. ___ PAPR 

6. ___ SCBA 

7. ___ Other 

Describe:_______________________ 

 

 33f. Were you fit tested for this respirator? 1. ___ Yes 0. ___ No 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 41 

 34. Do you ever clean equipment with a vacuum cleaner? 1. ___ Yes 0. ___ No 

35. Do you ever clean your clothes with compressed air at work? 1. ___ Yes 0. ___ No 

36a. Do you ever wear a mask or respirator during your regular work 1. ___ Yes 0. ___ No 

 activities, other than when cleaning with compressed air or bagging 

 flock or cotton? 

IF YES: 

36b. What percent of the time do you wear a mask or respirator ______ Percent 

 when performing your regular work activities? 

36c. Which type of mask or respirator do you wear? (See Diagram) 1. ___ Single strap 

 2. ___ 2-strap 

3. ___ Half face piece 

4. ___ Full face piece 

5. ___ PAPR 

6. ___ SCBA 

7. ___ Other 

Describe:_______________________ 

 

36d. Were you fit tested for this respirator? 1. ___ Yes 0. ___ No 

37a. Have you noticed material(s) at work that cause you to have 1. ___ Yes 0. ___ No 

 chest symptoms such as cough, phlegm, wheezing, 

 attacks of wheezing, or shortness of breath? 

 IF YES, describe the material(s) and associated chest symptom(s): 

 

MATERIAL CHEST SYMPTOM 

37b1. _______________________________________ _______________________________________ 

37b2. _______________________________________ _______________________________________ 

37b3. _______________________________________ _______________________________________ 

37b4. _______________________________________ _______________________________________ 

 
Page 42 Health Hazard Evaluation Report No. 2004-0186-3011 

38. I’m now going to ask you to list all the jobs that you have held at Claremont Flock Co. We will begin with your curr

through time. 

 Job Title Department Start Date 

Month/Year 

A B C D E F G H I J 
Health Hazard Evaluation Report No. 2004-0186-3011 Page 43 

 Section V - Cigarette Smoking History 

I’m now going to ask you a few questions about tobacco use. 

39a. Have you ever smoked cigarettes regularly? 1. ___ Yes

 0. ___ No 

 (YES if smoked 100 cigarettes or more 

 in your entire life; 100 cigarettes = 5 packs.) 

If YES: 

39b. How old were you when you first started _______ 

Years old 

 smoking cigarettes regularly? 

39c. On average, for the entire time that you smoked, _______ 

Cigarettes per day 

 how many cigarettes did you smoke per day? 

 (20 cigarettes = 1 pack) 

39d. Do you still smoke cigarettes (as of 1 month ago)? 1. ___ Yes

 0. ___ No 

 If NO: 

 39e. How old were you when you stopped smoking _______ 

Years old 

 cigarettes regularly? 

Thank you for participating in this survey! 
DEPARTMENT OF HEALTH AND HUMAN SERVICES 

Centers for Disease Control and Prevention National Institute for Occupational Safety and Health 4676 Columbia Parkway Cincinnati, OH 45226-1998 OFFICIAL BUSINESS Penalty for private use $300 

Delivering on the Nation's promise: 

Safety and Health at work for all people 

through research and prevention

To receive NIOSH documents or information 

about occupational Safety and Health topics 

contact NIOSH at: 

1-800-35-NIOSH (356-4674) 

Fax: 1-513-533-8573 

E-mail: pubstaft@cdc.gov 

or visit the NIOSH web site at: 

http://www.cdc.gov/niosh 

S A F E R • H E A L T H I E R • P E O P L ETM