NIOSH HEALTH HAZARD EVALUATION REPORT:

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

National Institute for Occupational Safety and Health

HETA #99–0113–2853

University of California, Berkeley

Berkeley, California

July 2001

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports

This Health Hazard Evaluation (HHE) report and any recommendations made herein are for the specific facility evaluated and may not be universally

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

applicable. Any recommendations made are not to be considered as final statements of NIOSH policy or of any agency or individual involved.

Additional HHE reports are available at http://www.cdc.gov/niosh/hhe/reports
ii

PREFACE

The Hazard Evaluations and Technical Assistance Branch (HETAB) 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 (OSHA) Act of 1970, 29 U.S.C. 669(a)(6) which authorizes the Secretary of Health and

Human Services, following a written request from any employer or authorized representative 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.

HETAB 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

This report was prepared by Aaron Sussell and Greg Piacitelli of the NIOSH Division of Surveillance, Hazard

Evaluations and Field Studies (DSHEFS). Zulfi Chaudhry, DSHEFS, provided data entry and data

management. Charles A. Mueller, DSHEFS, provided statistical analyses of the data. 

This study would not have been possible without the support and cooperation of the Department of

Environment, Health & Safety, UC Berkeley, and California members of the Painting and Decorating

Contractors of America (PDCA). We gratefully acknowledge the planning time, labor, and materials

provided by participating contractors including Burt Olhiser of Hazard Management Services, Inc.; Steve

Jeffress, Jeffco Painting & Coating, Inc.; Bob Spurgeon, Spurgeon Painting; Bob O’Brien, O’Brien Painted

to Last; Don O’Brien, O’Brien Painting; David and Jeanne Moore, North Coast Painting, and the Golden Gate

Chapter of the Associated Builders and Contractors (ABC).

The following persons provided invaluable assistance and support during the field investigation: Kevin

Roegner, Zulfi Chaudhry, and Tami Wise, NIOSH; Gary Bayne and Christine Little, Department of

Environment, Health & Safety, UC Berkeley, and Jennifer Portera, industrial hygienist. Analytical support

was provided by DataChem Laboratories. Desktop publishing was performed by Ellen E. Blythe. Review

and preparation for printing were performed by Penny Arthur.

Copies of this report have been sent to employee and management representatives at UC Berkeley and the

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

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.
iv

Highlights of the NIOSH Health Hazard Evaluation

Evaluation of Lead Exposures During Renovation of Building with Lead Paint

This NIOSH Health Hazard Evaluation was requested by the University of California, Berkeley. We

measured exposures during a 1999 demonstration project at three unoccupied campus buildings. The purpose

was to measure worker lead exposures, as well as lead levels (air and dust) in nearby areas during eight

renovation tasks. All of the tasks involved removing exterior lead-based paint, which is typically done prior

to repainting.

What NIOSH Did

# Took air samples for lead on workers for

eightdifferent tasks used to remove lead paint on

building exteriors.

# Collected air and settled dust samples to measure

lead in nearby areas during the same work periods.

# Collected a paint chip sample from each surface,

and measured production rate for each work period.

What NIOSH Found

# Task, worker, and paint lead concentration are

associated with renovation workers’ lead exposures.

# Tasks with high worker lead exposures were dry

manual sanding, dry manual scraping, power finish

sanding, and power finish sanding with bag.

# Tasks with lower worker lead exposures were

power sanding with HEPA exhaust, flame burning,

wet manual sanding, and wet scraping.

# All of the tasks can produce lead contamination

in nearby areas. Flame burning and power finish

sanding resulted in the highest levels of lead in air

and settled dust in nearby areas.

What University of California, Berkeley

Managers Can Do

# Whenever possible, use tasks with low worker

exposures for renovating surfaces with lead paint.

# When lead paint is present, avoid the tasks which

had the highest worker lead exposures and lead

levels in nearby areas.

# Require workers to wear protective clothing and

use good hygiene practices for all tasks when lead

paint is present.

# Where renovation work will disturb lead paint,

follow federal and state guidelines for lead-safe

work, including dust containment and clean up in

homes with lead paint.

What the University of California, Berkeley

Employees Can Do

# Use protective clothing and good hygiene when

doing any tasks on surfaces with lead paint.

# When working on surfaces with lead paint, clean

shoes and equipment daily, and clean your personal

vehicle often.

# Wear respirators when using high exposure tasks

on lead paint.

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 #99–0113–2853

Highlights of the HHE Report
v

Health Hazard Evaluation Report 99–0113–2853

University of California, Berkeley

Berkeley, California

July 2001

Aaron L. Sussell

Greg M. Piacitelli

SUMMARY

At the request of the University of California, Berkeley, the National Institute for Occupational Safety and Health

(NIOSH) conducted a study of lead–based paint (LBP) exposures during exterior renovation work on campus

buildings. Workers’ personal airborne lead (PbA) exposures were assessed for eight renovation tasks during a

three–day demonstration project. Additionally we measured concomitant area PbA concentrations 6 feet (ft) from

the work surfaces, lead in settled dust (PbS) at three distances (6, 10, and 20 ft) from work surfaces for five tasks,

and determined if these measures were correlated with the workers’ PbA exposures. Five workers performed

assigned renovation tasks during limited work periods (average time 28 minutes [min]) on 22 painted exterior

surface areas (wood windows, wood doors, and metal stairs). A total of 132 work periods were sampled; the work

took from 2 to 12 work periods per designated work surface, depending on the area. Lead concentrations in paint

chip samples (one per work surface) ranged from 0.23% to 34% lead (Pb) by weight (average 11.3%). Personal

PbA exposures were highly variable; range, none detected to 660 micrograms per cubic meter (:g/m3

), geometric

mean (GM) = 22 :g/m3

, geometric standard deviation (GSD) 4.3. Personal PbA exposures were significantly

associated with task, worker, and paint lead concentration (p <0.001). High–exposure tasks were dry manual

sanding (GM = 49 :g/m3

), dry manual scraping (53 :g/m3), power finish sanding (44 :g/m3), and power finish

sanding with bag (68 :g/m3

). Low–exposure tasks were power sanding with high–efficiency particulate air

(HEPA) exhaust (GM = 6.9 :g/m3

), wet manual sanding (6.2 :g/m3), wet manual scraping (16 :g/m3), and flame

burning (23 :g/m3

). The area PbA concentrations at 6 ft distance, which were also highly associated with task,

were roughly an order of magnitude below the personal exposures, ranging from none detected to 37 :g/m3

, GM

= 1.5 :g/m3

, GSD = 3.3. GMs for PbS samples were 3.2 milligrams per square meter (mg/m2) at 6 ft (n=69), 1.4

mg/m2

 at 10 ft (n=67), and 0.66 mg/m2 at 20 ft (n=39). Overall PbS levels decreased significantly as distance

increased (p <0.0001). At each distance PbS levels were significantly associated with task (p–values 0.024, 0.0015,

and <0.0001, respectively). Flame burning was among the tasks associated with the highest area PbA and PbS

levels, although personal exposures were relatively low. Surface paint lead concentrations were poorly correlated

with the PbA exposures (R = 0.30). Personal and area PbA levels were significantly correlated (R = 0.49,

p <0.0001). Both area and personal PbA concentrations were significantly correlated with PbS levels measured 6

ft and 10 ft from the work surfaces (R values 0.34 to 0.73). Area PbA levels were significantly correlated with the

PbS levels at 20 ft as well (R = 0.67). 
vi

Worker lead exposures for eight renovation tasks on building exteriors with LBP were highly variable. Based

on workers’ exposures, the eight renovation tasks evaluated fell into two exposure groups. Estimated

average exposures during dry manual sanding, dry manual scraping, power finish sanding, and power finish

sanding with bag would exceed the permissible exposure limit (PEL) within an 8–hr period. Estimated

average exposures for power sanding with HEPA exhaust, flame burning, wet manual sanding, and wet

scraping would be below the PEL. Although it resulted in relatively low worker exposures, flame burning

was among the tasks associated with the higher lead levels in air and settled dust levels in nearby areas. The

power finish sander with a cloth dust bag was not effective in controlling worker exposures; the

random–orbital power sanding equipped with HEPA–filtered exhaust ventilation appeared to be highly

effective. Recommendations are provided in this report to help prevent hazardous worker exposures to LBP

during renovation of surfaces with LBP.

Keywords: SIC 1521 (General Contractors–Single–Family Houses) lead, renovation, remodeling, painters,

lead–based paint, painting, lead hazard, housing, residential
TABLE OF CONTENTS

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

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

Highlights of the HHE Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv

Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . v

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

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

Methods ........................................................................... 2

Evaluation Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

Lead Exposure ................................................................... 4

Lead in Surface Dust and Soil ........................................................ 4

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

Air Lead Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

Dust Lead Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Correlations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Recommendations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Health Hazard Evaluation Report No. 99–0113 Page 1

INTRODUCTION

In 1999, the National Institute for Occupational

Safety and Health (NIOSH) received a request from

the Office of Environment, Health and Safety

(EH&S) at the University of California, Berkeley

(UC Berkeley) for an evaluation of worker lead

exposures during various renovation tasks requiring

the disturbance of lead–based paint (LBP). LBP is

defined by federal statute as paint with lead levels

equal to or exceeding 1.0 milligrams per square

centimeter (mg/cm2

) or 0.5% by weight [see the

Toxic Substances Control Act (TSCA) Section

401(9) (15 U.S.C. 2681(9)], U.S. Environmental

Protection Agency(EPA)). During a site visit in

March 1999, NIOSH investigators collected air and

settled dust samples during a three–day renovation

demonstration project which took place at

unoccupied university buildings. 

BACKGROUND

Renovators and painters throughout the United States

commonly encounter LBP in their work on buildings

and other structures. A national survey determined

that 83 percent of U.S. private housing units built

before 1980 have LBP.1

 Lead hazards are a concern

not only to residential renovation contractors but also

homeowners who work on their own houses.

The UC Berkeley EH&S department wanted to

determine which tasks which could be commonly

used to renovate campus buildings were the safest

for workers and occupants. Local members of the

Painting and Decoration Contractors of America

(PDCA) also had an interest in obtaining an

objective assessment of lead exposures for the work

tasks commonly performed by their members.

Therefore, the EH&S department and local PDCA

members arranged to conduct a demonstration

project to evaluate worker exposures to lead during

eight renovation tasks of interest. All of the tasks

involve removal of loose and deteriorated LBP from

exterior wood and steel surfaces on buildings to

prepare the surfaces for repainting. UC Berkeley

requested NIOSH technical assistance to conduct a

task–based assessment of worker exposures and

environmental lead levels resulting from these

renovation tasks. The tasks selected by UC Berkeley

and the local PDCA members were designated (task

number, name): (1) dry manual sanding, (2) dry

manual scraping, (3) flame burning, (4) power finish

sanding, (5) power finish sanding with bag (with

cloth bag dust collector), (6) power sanding with

high–efficiency particulate air (HEPA) (with HEPA

filtered local exhaust ventilation), (7) wet manual

sanding, (8) and wet manual scraping. The task

categories are described in more detail in Table 1;

photographs of the demonstration project are in

Figure 1. 

Uncontrolled power random–orbital sanding was not

included in this evaluation because the task is well

known to generate high lead exposures and UC

Berkeley policy prohibited its use on surfaces with

LBP. Federal guidelines for residential lead paint

work require that all orbital power sanders and

grinders be controlled with HEPA vacuum

attachments.2,3 The same guidelines also recommend

against using open flame burning. However,

participating PDCA members requested that open

flame burning be included in the study. They

reported that open flame burning is the best method

for certain renovation jobs, especially removal of

exterior LBP from decorative wood trim on historic

Victorian homes, and is used successfully by many

of their professional members not only in the San

Francisco Bay area but also across the country.

The primary purpose of the NIOSH study was to

assess worker personal airborne lead (PbA)

exposures for eight renovation tasks. Secondary

objectives were to (1) measure concomitant area PbA

levels 6 ft from the work surfaces, (2) measure lead

in settled dust (PbS) 6 to 20 feet from work surfaces

for five tasks, and (3) determine if area air and settled

dust levels were correlated with the workers’ PbA

exposures.

The project took place at three unoccupied buildings

on the UC Berkeley campus which were scheduled

for demolition: two 2–story multifamily residences

(Smyth–Fernwald Buildings C and D), and an

adjacent 11⁄2–story multipurpose building (known as
Page 2 Health Hazard Evaluation Report No. 99–0113

the “Daycare Center”). The building exteriors were

stucco, with painted wood windows (including

sashes, sill, and casing), wood doors (including

casing), and metal stairs and railings. Previous LBP

inspection had found that most of the exterior

surfaces, except the stucco siding, were coated with

LBP. The windows, door, and stair surfaces were

prepared as they normally would be for repainting

using the eight renovation tasks. After the

demonstration project was completed UC Berkeley

planned to demolish the buildings and perform a

clean up of the site.

Participating PDCA contractors provided five

workers, personal protective equipment, and the

tools needed. All of the participating workers had

previously completed training required by the

California Department of Health Services for

workers performing residential lead hazard reduction

work. The workers wore disposable paper coveralls

and half–mask air–purifying respirators with NIOSH

type N100 filters during all tasks. Hygiene facilities,

including running water, hand soap, disposable

paper towels, and a clean lunch room, were provided

inside the Daycare Center. 

METHODS

The demonstration project was conducted during a

three–day period. Seventeen exterior work locations

of approximately equal area were marked out on the

buildings. The locations included one or more

painted wood windows or doors (15 locations), and

exterior open metal stairs with LBP (two locations).

During the demonstration we discovered that the

buildings did not have enough painted work surfaces

to complete the scheduled number of work periods.

As a result, five surplus wood doors with LBP were

brought from another construction site. Since the

paint appeared to be in the same general condition,

both sides of each door was considered to be a single

work surface. The doors were treated by leaning

them against a wall at two of the designated

locations. With the addition of the doors, a total of

22 work surfaces (windows, doors, or stairs) were

used. The surfaces used generally had similar paint

condition, with minimal to moderate deterioration.

Stucco siding did not have LBP and was not

included as a work surface. The work was done on

the first story of the buildings, or on open stairs

between floors. It was necessary for some of the

workers to use ladders to reach the tops of windows

and their casings. 

During each work period, workers performed an

assigned task at one location for approximately 30

minutes. The five workers worked simultaneously; to

minimize cross–contamination, the locations which

were used were at least 50 ft apart. After each work

period, workers rotated between locations. Each

location was used for multiple work periods

involving different workers, and many were used for

multiple tasks. The surface area treated by the

worker, and the work time in minutes was measured

for each work period; the results were used to

calculate the production rate in square feet per hour

(ft2

/hr). 

Task–based air sampling was conducted during

separate work periods on three consecutive days.

During each work period, a breathing zone air

sample was collected on the worker to measure

personal airborne lead (PbA) exposure, and a paired

area PbA sample was collected 6 ft away

(perpendicular to wall) at the approximate midpoint

of the treated area. PbA samples were collected and

analyzed using NIOSH Method 7082 (flame atomic

absorption spectrophotometry). If no lead was

detected by this method, the samples were

subsequently analyzed using NIOSH Method 7105

(graphite furnace atomic absorption

spectrophotometry).4

 The flow rate used for PbA

samples was 4.0 liters per minute (Lpm). Pumps

were calibrated in the field pre– and post–sampling

daily; the average of the two flow measurements was

used in calculating results (differences between pre–

and post– were less than 5%). The limit of detection

(LOD) and limit of quantitation (LOQ) for PbA

samples were 0.1 and 0.4 micrograms (:g)/sample,

respectively (NIOSH Method 7105). PbA results are

reported in micrograms per cubic meter (:g/m3

).

Limited sampling for lead in PbS was done

concurrently with PbA sampling. Due to time and

resource limitations PbS sampling was limited to five
Health Hazard Evaluation Report No. 99–0113 Page 3

tasks (dry manual scraping, flame burning, power

finish sanding, power sanding with HEPA exhaust,

and wet manual scraping) on the first day and part

of the second day. On the first day, PbS samples

were collected during work periods at distances of

6 ft, 10 ft, and 20 ft from the work surface, measured

perpendicular to the wall. On the second day, PbS

samples were collected in the same manner but at the

6 ft and 10 ft distances only (no dust was visible on

samples collected at the 20 ft distance on the first

day). All of the PbS samples were collected on

pre–moistened 5.5–inch by 8.0–inch (0.029 square

meter [m2

]) towelettes (Wash'n Dri®, Softsoap

Enterprises, Inc, Chaksa, Minnesota), which have

been found to be suitable for PbS sampling.5

 To

collect a sample, a clean towelette was unfolded and

placed flat in a 6–inch by 9–inch rectangular plastic

storage tray (EKCO® Consumer Plastic Inc., model

No. 514–1). The towelette was re–wetted with

distilled water from a hand spray at intervals to keep

the towelette moist. At the end of each 30–min work

period, the towelette was folded inward upon itself to

contain any dust adhering to it, and placed in a

50–milliliter (mL) centrifuge tube. The samples were

analyzed for lead according to NIOSH Method 7105.

The LOD and LOQ for PbS samples were 0.07 and

0.2 :g/sample, respectively. Results are reported in

milligrams per square meter (mg/m2

).

At each work location, and for each of the surplus

wood doors used, one bulk paint sample was

collected according to American Society for Testing

and Materials (ASTM) Method E1729–99.6

 Paint

chips were collected from areas where the paint

was peeling, or, if there was no peeling paint, by

cold scraping with a stainless steel scraper. After

weighing, a 0.2 gram (g) portion of each sample was

prepared and analyzed by NIOSH Method 7082

(flame atomic absorption spectrometry).4

 Results

were reported as percent by weight. The LOD for

lead was 0.001% and the LOQ was 0.004%.

All of the laboratory lead analyses were reported

with a precision of two significant digits.

Accordingly, calculated results were rounded off to

two significant digits. For statistical purposes, the

respective LOD/(2(0.5)) was used to calculate an

estimated value for samples with no detectable lead.7

Statistical analyses were performed with StatView®

5.01 and SAS® for Windows, version 8, SAS

Institute, Inc.

EVALUATION CRITERIA

As a guide to the evaluation of the hazards posed by

workplace exposures, NIOSH field staff employ

environmental evaluation criteria for the assessment

of a number of chemical and physical agents. These

criteria are intended to suggest levels of exposure to

which most workers may be exposed up to 10 hours

per day, 40 hours per week for a working lifetime

without experiencing adverse health effects. It is,

however, important to note that not all workers will

be protected from adverse health effects even though

their exposures are maintained below these levels. A

small percentage may experience adverse health

effects because of individual susceptibility, a

pre–existing medical condition, and/or a

hypersensitivity (allergy). 

The primary sources of environmental evaluation

criteria for the workplace are: (1) NIOSH

Recommended Exposure Limits (RELs),8

 (2) the

American Conference of Governmental Industrial

Hygienists’ (ACGIH®) Threshold Limit Values

(TLVs®),9

 and (3) the U.S. Department of Labor,

Occupational Safety and Health Administration

(OSHA) Permissible Exposure Limits (PELs).10

OSHA requires an employer to furnish employees a

place of employment that is free from recognized

hazards that are causing or are likely to cause death

or serious physical harm [Occupational Safety and

Health Act of 1970, Public Law 91–596, sec.

5.(a)(1)]. Not all hazardous chemicals have specific

OSHA exposure limits such as PELs and short–term

exposure limits (STELs). An employer is still

required by OSHA to protect their employees from

recognized hazards, even in the absence of a specific

OSHA PEL.

A time–weighted average (TWA) exposure refers

to the average airborne concentration of a substance

during a normal 8– to 10–hour workday. Some

substances have recommended STEL or ceiling
Page 4 Health Hazard Evaluation Report No. 99–0113

values which are intended to supplement the TWA

where there are recognized toxic effects from higher

exposures over the short–term.

Lead Exposure

Occupational exposure occurs via inhalation of

lead–containing dust and fume, and ingestion from

contact with lead–contaminated surfaces. Symptoms

of lead poisoning include weakness, excessive

tiredness, irritability, constipation, anorexia,

abdominal discomfort (colic), fine tremors, and

“wrist drop.”11,12,13 Exposure to lead over time can

cause harm gradually, with no obvious symptoms or

clinical effects. Chronic exposure to lead may cause

damage to the kidneys, anemia, hypertension,

infertility and reduced sex drive in both sexes, and

impotence. Exposure to lead before or during

pregnancy can alter fetal development and cause

miscarriages. The developing nervous system of the

fetus is particularly vulnerable to lead toxicity.14

A person’s lead exposure can be readily determined

by biological monitoring. The blood lead level

(BLL) is the best indication of recent exposure to,

and current absorption of, lead.15 Measurement of

zinc protoporphyrin (ZPP) level in blood is a good

indicator of chronic lead exposure because the toxic

effect of lead on heme synthesis in red blood cells

causes elevated ZPP levels. Persons without

occupational exposure to lead usually have a ZPP

level of less than 40 micrograms per deciliter

(:g/dL).16 Elevated ZPP levels due to lead exposure

may remain months after the exposure. Because

other factors, such as iron deficiency, can also cause

an elevated ZPP level, the BLL is a more specific test

in the evaluation of occupational exposure to lead.

OSHA has established a PEL for lead in air (PbA) of

50 :g/m3

 as an 8–hour TWA, which is intended

to maintain worker BLLs below 40 :g/dL.17,18

OSHA has also established an action level for PbA of

30 :g/m3

 as an 8–hour TWA. OSHA requires that

employers provide protective measures to employees

exposed above the action level, such as medical

surveillance including BLL and ZPP sampling and

analysis. Medical removal protection is required

when an employee’s BLL reaches 50 :g/dL. 

NIOSH has concluded that the 1978 NIOSH REL of

100 :g/m3

 as an 8–hour TWA does not sufficiently

protect workers from the adverse affects of exposure

to inorganic lead.19 NIOSH intends to analyze the

feasibility of developing an REL that would provide

better protection for workers. NIOSH has conducted

a literature review of the health effects data on

inorganic lead exposure and finds evidence that some

of the adverse effects on the adult reproductive,

cardiovascular, and hematologic systems, and on

the development of children of exposed workers can

occur at BLLs as low as 10 :g/dL.14 At BLLs below

40 :g/dL, many of the health effects would not

necessarily be evident by routine physical

examinations, but represent early stages in the

development of disease. 

In recognition of the toxic effects of lead, voluntary

standards and public health goals have established

lower occupational exposure limits to protect

workers and their children. The ACGIH TLV® for

PbA is 50 :g/m3

 as an 8–hour TWA, with worker

BLLs to be controlled to #30 :g/dL.20 A national

health goal is to eliminate all occupational exposures

which result in BLLs greater than 25 :g/dL.21

Lead in Surface Dust and Soil

Lead contamination in dust and soil, which is

commonly found in the U.S. due to the past use of

lead in gasoline and paints, and also from industrial

emissions, is a risk to young children.

Lead–contaminated surfaces may be a source of

occupational exposure for workers. Lead exposure

may occur either by direct hand–to–mouth contact,

or indirectly through contamination of hands,

cigarettes, cosmetics, or food. 

In the workplace, generally there is little or no

correlation between lead in surface dust or soil and

employee exposures. The amount of lead ingested

by workers depends primarily on the effectiveness of

administrative controls (i.e., hazard communication),

hygiene practices, and hygiene facilities. There is no

federal standard for surface lead contamination in

workplaces, but there are standards for lead in

residential dust and soil designed to protect young

children. EPA has defined a dust–lead hazard as a
Health Hazard Evaluation Report No. 99–0113 Page 5

surface in a residential dwelling or child–occupied

facility that contains a lead loading equal to or

greater than 40 micrograms per square foot

(μg/ft2

–equivalent to 0.43 mg/m2); on floors or

250 μg/ft2 (equal to 2.7 mg/m2

) on interior window

sills based on wipe samples.22

Similarly, there are no federal standards for soil lead

contamination in the workplace. EPA has defined a

soil–lead hazard as bare soil on a residential real

property or on the property of a child–occupied

facility that contains total lead equal to or exceeding

400 parts per million (ppm) (equal to micrograms per

gram [μg/g]) in a play area or average of 1,200 ppm

in the rest of the yard based on soil samples.22

RESULTS

Lead concentrations in 22 paint chip samples (1 per

work surface) ranged from 0.23% to 34% Pb by

weight. Twenty–one of the 22 paint samples (95%)

had a lead concentration above the federal action

level of 0.5% Pb.23 The distribution of the results

adequately fit normal (Kolmogorov–Smirnov test).

The average paint lead concentration was 11.3%

(standard deviation [SD] 10%). Work surfaces were

used from 2 to 12 work periods depending on the

size of their area. Since surface areas available for

renovation were limited, workers maximized the

use of each surface area by performing the

designated task on all of the available area. The

surface–weighted average lead concentration

(( 3[surface Pb concentration x no. of times surface

was used]) ÷total no. of work periods) was 14.0%

(SD 10.8). 

A total of 132 work periods were sampled for PbA.

Some samples were lost due to sampling errors,

leaving 128 personal and 130 area PbA samples for

eight renovation tasks. The number of work periods

sampled per task ranged from 8 to 26. The number

of work periods sampled per worker ranged from 25

to 27: worker 1 was sampled 27 times, workers 2, 3,

and 4, were sampled 25 times, and worker 5 was

sampled 26 times. PbA, PbS, surface area treated,

and production rate results were natural log

transformed for data analyses; after transformation

the data distributions adequately fit normal

(Kolmogorov–Smirnov test). 

Weather conditions on the three days of

environmental sampling were cloudy to partly

cloudy, with light and variable winds. Although the

objective was to sample work periods of 30–min

duration, in practice the work periods varied from 13

to 76 min due to sampling or equipment problems

(mean 28 min, SD 6.0). The geometric mean (GM)

surface area treated was 5.2 ft2

 (geometric standard

deviation [GSD] 2.3, range 0.29 to 42 ft2

).

Production rates, expressed as ft2

/hour, are

summarized by task in Table 2. The production rate

data should be interpreted with caution. This data

was collected during a demonstration project where

workers did not have the time pressures of a real job.

Among 128 work periods with personal PbA results,

the GM production rate was 15 ft2

/hr (GSD 13, range

0.5 to 100 ft2

/hr). Flame burning (GM = 21 ft2/hr)

and dry manual scraping (18 ft2

/hr) had similar

production rates which were higher than the other

tasks evaluated. However, with one exception the

differences between task production rates did not

reach statistical significance. Flame burning had a

significantly higher production rate (GM = 21 ft2

/hr)

than power finish sanding (10 ft2

/hr),(p–value =

0.0058). 

Air Lead Results

Personal PbA exposures during 128 work periods

were highly variable, ranging from none detected

(estimated numeric value 0.39 :g/m3

) to 660 :g/m3,

GM = 22 :g/m3

, GSD 4.3. An analysis of

covariance (ANCOVA) was done to examine the

association of task, worker, paint lead concentration,

and production rate with the (log) personal PbA

levels. The overall model was highly significant.

However, since the production rate variable neither

contributed significantly to the model (p value =

0.56) nor varied significantly between workers

(p=0.40), this variable was dropped. 

PbA means were adjusted for the effects of task,

worker, and paint lead concentration (SAS® GLM

procedure, with least squares means). Personal PbA

exposures were jointly highly associated with task,
Page 6 Health Hazard Evaluation Report No. 99–0113

worker, and paint lead concentration variables

(p <0.001) in the final (adjusted) model. The most

important association in the final model was task

(p<0.001), followed by paint lead concentration

(p = 0.027) and worker (p = 0.042). The adjusted

and unadjusted means were very similar, with the

exception of two tasks: power finish sanding (task 4)

and power finish sanding with bag (task 5). The

surface paint lead concentration had an effect on the

means for tasks 4 and 5 because the mean paint

Pb levels for these two tasks (32% and 2.0%,

respectively) were quite different than means for the

other six tasks (range 9.4 – 13.9%). Differences in

personal PbA exposures between tasks 4 and 5 did

not reach statistical significance either before or

after adjustment.

The GM and 95% CLs (adjusted and unadjusted),

and minimum and maximum values for personal

PbA exposures by task are presented in Table 3. As

can be seen graphically in Figure 2, although PbA

exposures were highly variable, the tasks fall roughly

into two exposure groups. High–exposure tasks

were dry manual sanding (GM = 49 :g/m3

), dry

manual scraping (53 :g/m3

), power finish sanding

(44 :g/m3

), and power finish sanding with bag

(68 :g/m3

). Exposures during these four tasks were

not statistically different from each other but were

significantly higher than those during tasks 6–8.

Low–exposure tasks were power sanding with

HEPA exhaust (GM = 6.9 :g/m3

), wet manual

sanding (6.2 :g/m3

), wet manual scraping (16 :g/m3),

and flame burning (23 :g/m3

). Among the four

low–exposure tasks, only flame burning was

significantly different than any of the others. Flame

burning had significantly higher personal PbA

exposures than power sanding with HEPA exhaust

and wet manual sanding. Maximum exposures for

six of the eight tasks evaluated were greater than

50 :g/m3

; however, due to the high variability of

exposures within tasks they are not representative of

the workers’ average exposures for those tasks. The

maximum individual exposures for two

low–exposure tasks, power sanding with HEPA and

wet manual sanding, did not reach 50 :g/m3

.

For each task the 95% upper confidence limit (UCL)

for the adjusted GM was used to conservatively

estimate the time, on average, that a worker could

perform the task before his personal PbA exposure

reached the OSHA PEL–TWA (50 :g/m3

). The

estimated times are presented graphically in Figure 3.

It was estimated that the high–exposure tasks (dry

manual sanding, dry manual scraping, power finish

sanding, and power finish sanding with bag) would

result in a worker’s exposure reaching the OSHA

PEL in less than 8 hours. Estimated times to reach

the PEL ranged from 2.4 hours for power finish

sanding with bag to 4.4 hours for dry manual

scraping and power finish sanding. It was estimated

that the four low–exposure tasks (flame burning,

power sanding with HEPA exhaust, wet manual

sanding, and wet manual scraping) would not, on

average, result in a worker’s exposure reaching the

PEL within an 8–hour work shift. 

Results for the 130 TWA area PbA samples collected

6 ft from work surfaces are summarized by task in

Table 4. As a secondary outcomes, area PbA results

were not adjusted for the effects of other variables.

The area PbA concentrations overall were roughly an

order of magnitude below the personal exposures,

ranging from none detected (estimated value 0.08

:g/m3) to 37 :g/m3, GM = 1.5 :g/m3, GSD = 3.3.

Area PbA concentrations were highly associated with

task, (analysis of variance, p <0.0001); the

associations of other variables with area PbA levels

were not examined. Tasks associated with the

highest area PbA concentrations were power finish

sanding (GM = 5.9 :g/m3

), and power finish sanding

with bag (7.6 :g/m3

). These two tasks, which were

not statistically different from each other, had higher

area PbA levels than all the other tasks. Flame

burning (2.6 :g/m3

) was among the tasks with high

area PbA concentrations; it had significantly higher

area PbA concentrations than tasks 2, 6, 7, and 8.

Tasks associated with low area PbA levels were

power sanding with HEPA exhaust (GM = 0.60

:g/m3), wet manual sanding (0.73 :g/m3), and wet

manual scraping (0.65 :g/m3

). These three tasks,

which were not statistically different from each other,

also had the lowest personal PbA exposures. 

Dust Lead Results
Health Hazard Evaluation Report No. 99–0113 Page 7

PbS samples were collected for five of the tasks

(numbers 2, 3, 4, 6, and 8). Results for 69 PbS

samples at 6 ft, 67 samples at 10 ft, and 39 samples at

20 ft were obtained (two 10 ft samples were lost).

The average PbS sample duration was 31 min. At all

of the sample locations detectable amounts of lead

were measured; the PbS results by task are

summarized in Table 5. PbS results were not

adjusted for the effects of other variables.

PbS concentrations overall were highly variable,

ranging from 0.13 to 380 mg/m2

. Overall PbS levels

decreased significantly with distance at 6 ft ( GM =

3.2 mg/m2

, GSD = 4.4), 10 ft (1.4 mg/m2, GSD =

3.3), and 20 ft (0.66 mg/m2

, GSD = 2.3), ANOVA,

p–value <0.0001. At all three distances, the GM PbS

levels, resulting from an average work period of

30.6 min, were higher than the EPA standard for lead

loading on interior residential floors (0.43 mg/m2

).

At each distance, PbS levels were significantly

associated with task (ANOVA p–values 0.024,

0.0015, and <0.0001, respectively). Flame burning

and power finish sanding were associated with higher

PbS levels than the other tasks at all distances. The

differences at 6 ft and 10 ft did not reach statistical

significance; at the 20 ft distance PbS levels from

flame burning (GM = 1.7 mg/m2

) and power finish

sanding (1.0 mg/m2

) were significantly higher than

levels from all other tasks (range of GMs: 0.26 – 0.66

mg/m2

) in paired comparisons. PbS levels did not

differ significantly between power sanding with

HEPA exhaust and wet manual scraping at any

distance. 

Correlations

As shown in Figure 4, surface paint lead

concentrations were relatively poorly correlated with

the (log) PbA exposures (R = 0.30). Personal and

area PbA levels were significantly correlated, R =

0.49, p <0.0001, see Table 6. Both area and personal

PbA concentrations were significantly correlated

with PbS levels at 6 ft and 10 ft from the work

surfaces, R values 0.34 to 0.73. Area PbA levels

were significantly correlated with the PbS levels at

20 ft as well, R = 0.67. The PbS levels at 6 ft and

10 ft levels were more highly correlated with the area

PbA concentrations than with the personal PbA

levels. This is an expected result because the area

PbA sample locations (6 ft from the work surfaces)

were closer to the PbS sample locations than the

worker personal sample. 

DISCUSSION

Lead levels in personal and area air, and settled dust

samples were measured for eight renovation tasks

performed on exterior windows, doors, and staircases

with LBP. Nearly all of the work surfaces had lead

concentrations greater than the EPA statutory limit

for LBP ($ 0.5% Pb), and the average surface lead

concentration, weighted by the number of times

each surface was used, was 28 times the statutory

definition of LBP. 

In considering these results it is important to

recognize that the study took place on exterior

surfaces of buildings and the results cannot be

generalized to interior work. It is likely that the

airborne lead concentrations and settled dust levels

would have been higher if the work was done

indoors. Indoors typically there is less ventilation

and less air volume for dispersion of lead–containing

dust.

Employers have expressed interest in having an

action level for lead in construction based on paint

lead concentrations. Previous NIOSH studies have

concluded that worker lead exposures during LBP

abatement and renovation work are highly variable

and that when paint lead concentrations and

task–based worker exposures are compared, there

is little or no correlation between these two

variables.14,24 This study found the same result;

worker exposures during some of the renovation

tasks were highly variable, and overall they were

poorly correlated with paint lead concentrations.

OSHA has concluded that is not possible to establish

an action level for construction work based on paint

lead concentrations; instead the OSHA action level is

based on personal PbA exposure monitoring.25

When task, worker, and paint lead concentration

were analyzed, these variables were jointly
Page 8 Health Hazard Evaluation Report No. 99–0113

significantly associated with the workers’ lead

exposures. Of these variables, the one which the

employer can readily control is the selection of task,

and the task clearly had the most important effect

on workers’ personal exposures. The significant

differences between workers suggest that individual

variations in work practices can be important, even

among trained workers. The production rate (surface

area treated per hour) was not associated with the

workers’ lead exposures under study conditions.

The high–exposure tasks were dry manual sanding,

dry manual scraping, power finish sanding, and

power finish sanding with bag. It was estimated that,

on average, these four tasks would result in a

worker’s exposure exceeding the OSHA PEL within

an 8–hour work shift. Lower worker exposures were

measured during power sanding with HEPA exhaust,

flame burning, wet manual sanding, and wet

scraping. It was estimated that, on average, none of

these methods would result in a worker’s exposure

reaching the OSHA PEL during the work shift.

Flame burning had significantly higher personal

exposures than power sanding with HEPA exhaust

and wet manual sanding. Of the tasks evaluated,

power sanding with HEPA exhaust and wet manual

sanding had the lowest worker lead exposures and

area airborne lead levels 6 ft from work surfaces. 

On some jobs where LBP is present, workers are

reportedly required to wear respirators all the time.

These results indicate that such a blanket

requirement is not appropriate for work on exterior

surfaces with LBP. Wearing air–purifying

respirators should only be required when they are

necessary to protect against an airborne toxic

exposure, because wearing a respirator (a) stresses

the worker’s cardiovascular and respiratory systems,

(b) reduces worker comfort, productivity, and safe

communication with other workers, and (c) can

increase the potential for heat stress.

Tasks which were associated with the highest area

airborne lead concentrations were power finish

sanding, power finish sanding with bag, and flame

burning. Overall the area airborne lead

concentrations at 6 ft from the work surfaces were

highly correlated with lead in settled dust collected at

6, 10, and 20 ft from the work surfaces. 

It is puzzling that flame burning was among tasks

associated with high area air and settled dust lead

levels but not one of the methods with the highest

worker lead exposures. More detailed investigation

would be needed to determine the reason for this. It

may be that workers kept the open flame torch

further from their faces than the other tools.

Increased distance between the paint removal tool

and workers’ breathing zones may have reduced

personal lead exposures without affecting nearby

area air and settled dust levels. The use of open

flame burning or heat guns above 1100° F for paint

removal is not recommended under HUD’s

federal guidelines for lead paint safety.2

 The

recommendation is based in part on a presumption

that high levels of lead dust will result. This study

confirms that flame burning can produce relatively

high air and settled dust lead levels in nearby areas (6

to 20 ft from work surfaces). Additionally, both

flame burning and heat gun can produce other toxic

vapors from decomposition of paint and can be a

serious fire hazard.

The average amounts of lead found in settled dust

after short work periods (average PbS sample time of

31 min) decreased significantly with distance from 6

to 20 ft from the work surfaces. Overall, the average

lead loadings at all three distances (6, 10, and 20 ft)

exceeded the current EPA standard for lead dust

on interior floors of residences. Tasks which were

associated with the highest levels of lead in settled

dust, particularly at 20 ft from work surfaces, were

power finish sanding and flame burning. It is likely

that these tasks produced fine particles more easily

carried by the natural ventilation which occurs

outside. 

While the results show that renovation work can

potentially contaminate soil up to 20 ft from work

exterior work surfaces, the health significance of the

settled dust lead levels cannot be determined from

this study. The samples were collected from ground

level after short work periods and do not reflect the

accumulated total lead levels on the soil after job

completion and site clean up. A previous NIOSH
Health Hazard Evaluation Report No. 99–0113 Page 9

study of renovation work in homes with LBP found

that average PbS levels in homes undergoing

renovation, and in workers’ and volunteers’ vehicles,

represented a potential health hazard to young

children.24 A 1991 federal study of residential lead

abatement work found that soil lead levels next to

homes undergoing LBP abatement were increased by

the work in spite of contractors’ efforts to contain

the dust.26 However, that study also found that even

before work began, average soil lead levels near

urban homes with LBP were high—nearly twice the

current EPA soil lead standard of 400 ppm.

Federal and California guidelines for renovation of

homes with LBP recommend that plastic sheeting be

used to protect the ground and shrubbery from the

base of the walls to a distance of at least 10 ft.2,27

Additionally, these guidelines recommend that

specialized clean up procedures be used at the end of

the renovation jobs to reduce lead contamination.

The effectiveness of the engineering controls

evaluated was mixed. The power finish sander with

perforated sandpaper and a dust collection bag was

ineffective in controlling worker exposures or nearby

area airborne lead concentrations. In contrast, the

random–orbital power sander, equipped with

perforated sandpaper and HEPA–filtered local

exhaust ventilation, appeared to be highly effective in

controlling worker exposures and area lead

concentrations. Previous studies of LBP removal

by uncontrolled power sanding have found worker

exposures up to 100 times the PEL.14 The results

show that worker exposures and area lead levels

during power sanding with HEPA exhaust were not

significantly different from the other low exposure

methods, wet manual scraping and wet manual

sanding. The power sander with HEPA exhaust

ventilation also was associated with relatively low

levels of lead in settled dust at distances of 6 to 20 ft

from the work surfaces.

RECOMMENDATIONS

The following recommendations are offered to assist

UC Berkeley and the participating contractors in

protecting workers and occupants from hazardous

lead–based paint exposures during future exterior

renovation work on surfaces with LBP. They are

based on the study results and previous NIOSH

evaluations of similar LBP work.28,29

1. Whenever possible, use low–exposure methods,

i.e., power sanding with HEPA exhaust, wet manual

sanding, or wet scraping. For exterior work,

respirators should not be routinely required for these

tasks. Where circumstances create, or observations

indicate, a potential for higher exposures, provide

respirators until an initial exposure assessment is

done to confirm the actual exposure levels. 

2. Avoid prolonged use of high–exposure tasks,

i.e., exterior dry manual scraping, dry sanding, power

finish sanding, and power finish sanding with bag. If

it is necessary to use one of these high–exposure

tasks, workers should be routinely provided with, and

wear, appropriate respirators in the context of a

respiratory protection program. Half–mask

air–purifying respirators (either single–use or

reusable) with high efficiency (NIOSH N100) filters

provide adequate protection for these tasks during

exterior work (a higher level of respiratory protection

should be provided for interior work). 

3. Based on its potential to contaminate nearby

areas (air and settled dust) with high levels of lead,

and create other hazards for the worker, open flame

burning should be avoided. Federal guidelines for

renovation work (published by the U.S. Department

of Housing and Urban Development [HUD] and

EPA) mandate that this method is never acceptable

for removing LBP on federally–supported projects

due to the combined hazards of airborne lead, and

other toxic emissions from heating/burning paint, and

the fire hazard.2,3

4. For all renovation work where LBP is present,

contractors should provide lead hazard training,

and require workers to wear protective clothing and

use good hygiene practices.2,3 Portable handwashing

facilities should be provided by the contractor if

acceptable hygiene facilities are not available at

the work site. To prevent take home of lead via

personal vehicles, workers and site supervisors

should: (a) clean shoes daily, (b) use washable
Page 10 Health Hazard Evaluation Report No. 99–0113

1. EPA [1995]. Report on the national survey of

lead–based paint in housing: Base report.

Washington, DC: U.S. Environmental Protection

Agency. Publication No. EPA 747–R95–003.

2. HUD [1999]. Lead paint safety, a field guide

for painting, home maintenance and renovation

work. Washington, DC: U.S. Department of

Housing and Urban Development, Office of Lead

Hazard Control. Publication No. HUD

1779–LHC.

3. EPA [1994]. Reducing lead hazards when

remodeling your home. Washington, DC: U.S.

Environmental Protection Agency. Publication

No. EPA 747–R–94–002.

4. NIOSH [1994]. NIOSH manual of analytical

methods, 4th edition. Eller, P and Cassinelli, ME,

Eds. Cincinnati, OH: U.S. Department of Health

and Human Services, Public Health Service,

Centers for Disease Control and Prevention,

National Institute for Occupational Safety and

Health, DHHS (NIOSH) Publication No. 94–113.

5. Millson M, Eller PM, Ashley K [1994].

Evaluation of wipe sampling materials for lead in

surface dust. Am Ind Hyg Assoc J 55:339–342.

6. ASTM [2000]. E1729–99 Standard Practice

for Field Collection of Dried Paint Samples for

Lead Determination by Atomic Spectrometry

Techniques. West Conshohocken, PA: American

Society for Testing and Materials.

7. Hornung RW, Reed LD [1990]. Estimation

of average concentration in the presence of non

detectable values. Appl Occup Environ Hyg

5:46–51.

8. NIOSH [1992]. Recommendations for

occupational safety and health: compendium of

policy documents and statements. Cincinnati, OH:

U.S. Department of Health and Human Services,

Public Health Service, Centers for Disease Control

and Prevention, National Institute for

Occupational Safety and Health, DHHS (NIOSH)

Publication No. 92–100.

9. ACGIH [2001]. 2001 TLVs® and BEIs®:

threshold limit values for chemical substances and

physical agents. Cincinnati, OH: American

Conference of Governmental Industrial

Hygienists.

10. CFR [1997]. 29 CFR 1910.1000. Code of

Federal regulations. Washington, DC: U.S.

Government Printing Office, Office of the Federal

Register.

11. Hernberg S, et al. [1988]. Lead and its

compounds. In: Occupational Medicine. 2nd ed.

Chicago, IL: Year Book Medical Publishers. 

12. Landrigan PJ, et al. [1985]. Body lead

burden: summary of epidemiological data on its

relation to environmental sources and toxic

effects. In: Dietary and environmental lead:

human health effects. Amsterdam: Elsevier

Science Publishers.

13. Proctor NH, Hughes JP, Fischman ML

[1991]. Lead. In: Chemical Hazards of the

Workplace. 3rd ed. Philadelphia, PA: J.B.

Lippincott Company, pp 353–357.

14. Sussell A, et al. [1998]. Protecting workers

exposed to lead–based paint hazards: A report to

Congress. Cincinnati, OH: U.S. Department of

Health and Human Services, Centers for Disease

Control and Prevention, National Institute for

Occupational Safety and Health, DHHS (NIOSH)

Publication No. 98–112. January 1998–revised

with minor technical changes.

plastic floor mats in their vehicles, and (c) regularly

clean their vehicles. 

5. Where renovation work will disturb lead paint,

follow federal and state standards and guidelines for

lead–safe work, including accepted procedures for

dust containment and site clean up in homes with

lead paint.2,3,18

REFERENCES
Health Hazard Evaluation Report No. 99–0113 Page 11

15. NIOSH [1978]. Occupational exposure to

inorganic lead. Cincinnati, OH: U.S. Department

of Health, Education, and Welfare, Public Health

Service, Center for Disease Control, National

Institute for Occupational Safety and Health,

DHEW (NIOSH) Publication No. 78–158.

16. Lauwerys RR and Hoet P [1993]. Industrial

chemical exposure: guidelines for biological

monitoring, Second Edition. Ann Arbor, MI:

Lewis Publishers, p. 62.

17. CFR. Code of Federal regulations. OSHA

lead standard for general industry. 29 CFR,

Part 1910.1025. Washington, DC: U.S.

Government Printing Office, Office of the Federal

Register. 

18. CFR. Code of Federal Regulations. OSHA

construction industry lead standard. 29 CFR, Part

29 CFR 1926.62. Washington, DC: U.S.

Government Printing Office, Office of the Federal

Register.

19. 62 Fed. Reg. 206 [1997]. National Institute

for Occupational Safety and Health: occupational

exposure to inorganic lead: request for comments

and information.

20. ACGIH [2001]. 2001 TLVs® and BEIs®.

Cincinnati, OH: American Conference of

Governmental Industrial Hygienists.

21. DHHS [2000]. Healthy people

2010–conference edition; National health

promotion and disease objectives. Washington,

DC: U.S. Department of Health and Human

Services. Available on the internet at:

www.health.gov/healthypeople/Document/defau

lt.htm

22. 66 Fed. Reg. No. 4 [2001]. U.S.

Environmental Protection Agency: Lead–based

paint hazards, January 5, 2001. (To be codified at

40 CFR Part 745)

23. HUD [1995]. Guidelines for the evaluation

and control of lead–based paint hazards in

housing. Washington, DC: U.S. Department of

Housing and Urban Development, Office of Lead

Hazard Control.

24. Sussell A, Gittleman J, Singal M [1998].

Worker lead exposures during renovation of

homes with lead–based paint. Applied Occ and

Env Hygiene 13(11):770–775.

25. 58 Federal Register No. 84 [1993].

Occupational Safety and Health Administration:

Supplementary information, (E) Reasons for

differences with HUD Guidelines on certain

provisions. Lead exposure in construction;

Interim final rule, pp. 26593–94.

26. HUD [1991]. The HUD lead–based paint

abatement demonstration (FHA). Washington,

DC: U.S. Department of Housing and Urban

Development, Dewberry & Davis contract report

HC–5831, August 1991.

27. CDHS [1999]. Painting contractor's guide to

lead safety. Berkeley, CA: California Department

of Health Services, Occupational Lead Poisoning

Prevention Program.

28. Sussell A, Gittleman J, Singal M [1998].

Worker lead exposures during renovation of

homes with lead–based paint. Applied Occ and

Env Hygien 13(11):770–775.

29. NIOSH [2000]. Hazard evaluation and

technical assistance report: Rhode Island

Department of Health, Cincinnati, OH: U.S.

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Health, NIOSH Report No. HETA 96–200–2799.
Page 12 Health Hazard Evaluation Report No. 99–0113

Table 1. Description of Renovation Tasks Evaluated

Task No. Task Name Work Description

1 Dry manual sanding Hand sanding of painted surfaces with 80–grit aluminum oxide

sandpaper with folded full sheet or with a hand sanding block.

2 Dry manual scraping

Complete or partial removal of paint by manual scraping with

pull scrapers fitted with replaceable 2–inch tungsten–carbide

blades. 

3 Flame burning

Complete removal of paint by heating with propane torch

flame and then manual scraping with a steel blade with 2–inch

triangular tip.

4 Power finish sanding

Power sanding painting surfaces with 80–grit aluminum oxide

sandpaper on a quarter sheet palm grip sander (Dewalt® model

DW411). Non perforated sandpaper was used, so the sander’s

integral cloth dust bag was not functional.

5 Power finish sanding

with bag

Power sanding painting surfaces with 80–grit, 9–hole

aluminum oxide sandpaper on a quarter sheet palm grip sander

with cloth dust bag (Dewalt® model DW411).

6 Power sanding

with HEPA

Power sanding painted surfaces with 100– or 120–grit, 5–inch,

8–hole aluminum oxide sanding discs on a 5–inch

random–orbital sander (Bosch® model 3107 DVS) connected to

a HEPA vacuum (Pullman–Holt® model 102) rated at 100

cubic feet per minute.

7 Wet manual sanding

Hand sanding of painted surfaces with 80–grit sandpaper with

folded full sheet or with a hand sanding block. Surfaces (small

areas) were wetted with water using trigger–spray bottles.

8 Wet manual scraping

Complete or partial removal of paint by manual scraping with

pull scrapers fitted with replaceable 2–inch tungsten–carbide

blades. Surfaces (small areas) were wetted with water using

trigger–spray bottles.
Health Hazard Evaluation Report No. 99–0113 Page 13

Table 2. Production Rates for Eight Renovation Tasks, 128 Work Periods

Task No. Task Count

Production Rate ft2

/hr

Pairs with

Significant

Difference

GMA 95% Confid.

Limits B

1 Dry manual sanding 8 13 0.68 25

2 Dry manual scraping 17 18 5.8 30

3 Flame burning 26 21 17 25 3,4 p = 0.0058 

4 Power finish sanding 18 10 7.5 13 3,4 p = 0.0058

5 Power finish sanding

with bag 7 13 8.2 18

6 Power sanding with

HEPA exhaust 24 15 10 19

7 Wet manual sanding 8 12 0.92 22

8 Wet manual scraping 20 14 9.8 18

All Tasks 128 15 13 18

† least squares means adjusted for the effects of paint lead concentration and worker.

A geometric mean

B lower and upper 95% confidence limits for the geometric mean
Page 14 Health Hazard Evaluation Report No. 99–0113

Table 3. TWA Personal PbA Exposures for Eight Renovation Tasks (:g/m3)

Task

No. Task Count Range of Values

Unadjusted Values Adjusted Values† 

GMA 95%

Confid. Limits B

GMA 95%

Confid. Limits B

1 Dry manual sanding 8 11 – 220 44 19 100 49 22 108 2 Dry manual scraping 18 12 – 660 56 31 99 53 31 90 3 Flame burning 26 1.8 – 160 20 13 32 23 15 37 4 Power finish sanding 18 0.39C – 380 75 35 160 44 22 90 

5 Power finish sanding with

bag

7 31 – 81 44 32 59 68 28 167 

6 Power sanding with HEPA

exhaust

25 1.6 – 37 6.8 4.8 9.9 6.9 4.4 11 

7 Wet manual sanding 8 1.8 – 13 5.9 3.3 10 6.2 2.8 14 8 Wet manual scraping 18 0.13D – 200 14 6.8 29 16 9.3 27 

All Tasks 128 0.13D – 660 22 17 28

† least squares means adjusted for the effects of paint lead concentration and worker.

A geometric meanB lower and upper 95% confidence limits for the geometric meanC None detected result; the LOD/2(0.5) was used to calculate an estimated numerical value.D Semi–quantitative value, analytical result was between the LOD and LOQ.
Health Hazard Evaluation Report No. 99–0113 Page 15

Table 4. TWA Area PbA Concentrations 6 ft Away from

Work Surfaces for Eight Renovation Tasks, (:g/m3

)

Task

No. Task Count Range of Values

Unadjusted Values Significantly

Different

(p<0.05) than

Other Tasks

GMA 95% Confid.

Limits B

1 Dry manual sanding 8 0.57C – 7.2 1.5 0.74 3.2 4–6, 8

2 Dry manual scraping 18 0.49C

 – 4.1 0.90 0.64 1.3 3–5

3 Flame burning 26 0.36C

 – 13 2.6 1.8 3.8 2, 4–8

4 Power finish sanding 18 0.92D – 37 5.9 3.5 10 1–3, 6–8

5 Power finish sanding

with bag

7 4.8 – 16 7.6 5.0 12 1–3, 6–8

6 Power sanding with

HEPA exhaust

25 0.31C

 – 2.7 0.60 0.47 0.76 1, 3–5

7 Wet manual sanding 8 0.40C

 – 2.5 0.73 0.45 1.2 3–5

8 Wet manual scraping 20 0.08D – 1.9 0.65 0.48 0.90 1, 3–5

All Tasks 130 0.08D – 37 1.5 1.2 1.8

A geometric mean

B lower and upper 95% confidence limits for the geometric mean

C None detected result; the LOD/2(0.5) was used to calculate an estimated numerical value.

D Semi–quantitative value, analytical result was between the LOD and LOQ.
Page 16 Health Hazard Evaluation Report No. 99–0113

Table 5. PbS Concentrations at 6 ft, 10 ft, and 20 ft Perpendicular from Work Surfaces, Eight Renovation Tasks 

Task No. Task

PbS 6 ft PbS 10 ft 

Count Range of Values GMA (95% Cls)B Count Range of Values GMA (95% Cls)B Count Ran

Va

2 Dry manual

scraping

14 0.42 – 380 3.8

(1.2, 12)

14 0.19 – 23 1.1

(0.40, 2.1)

8 0.13 

3 Flame burning 13 0.32 – 248 5.8

(1.5, 17)

13 0.32 – 24 2.6

(1.2, 5.9)

7 0.73 

4 Power finish

sanding

14 2.5 – 19 5.8

(4.0, 8.4)

14 1.2 – 8.2 3.0

(2.2, 4.3)

8 0.46 

6 Power sanding with

HEPA exhaust

15 0.56 –2.7 1.3

(0.95, 1.7)

13 0.42 – 1.8 0.81

(0.61, 1.1)

9 0.34 

8 Wet manual

scraping

13 0.35 – 160 2.4

(0.93, 6.4)

13 0.18 – 7.4 0.87

(0.43, 1.7)

7 0.17 

All Tasks 69 0.32 – 380 3.2

(2.3, 4.6)

67 0.18 – 24 1.4

(1.0, 1.9)

39 0.13 

A geometric meanB lower and upper 95% confidence limits for the geometric mean
Health Hazard Evaluation Report No. 99–0113 Page 17

Table 6. Correlations Between Log PbA and Log PbS Measurements for Eight Renovation tasks.

Pearson R values (number of paired observations).

PbA, personal PbA, area PbS 6 ft PbS 10 ft PbS 20 ft

PbA, personal 0.49**

(128)

0.34*

(65)

0.45*

(63)

0.14†

(35)

PbA, area 0.55**

(67)

0.73**

(65)

0.67**

(37)

PbS 6 ft 0.78**

(67)

0.67**

(39)

PbS 10 ft 0.82**

(39)

** p value <0.0001

* p value <0.01

† p value = 0.44
Page 18 Health Hazard Evaluation Report No. 99–0113

Clockwise from upper left: task 1 with personal and 6–ft PbA samples; task 8 with 6– and 10–ft PbS samples; task 1; task 2; task 3;

tasks 4 and 5; task 6; task 7; and task 8.

Figure 1. Sampling set up and tasks, study of lead exposures during renovation, UC Berkeley.
Health Hazard Evaluation Report No. 99–0113 Page 19

0

20

40

60

80

100

120

140

160

12345678

Task

PbA

GM 

95 % 

confidence

interval

Figure 2. Geometric means and 95 % confidence intervals for personal PbA exposures (:g/m3),

eight renovation tasks. Task means were adjusted for the effects of worker and paint

lead concentration.

Task

s: (1) dry manual sanding; (2) dry manual scraping; (3) flame burning; (4) power finish sanding; (5) power finish sanding with

bag; (6) power finish sanding with HEPA exhaust; (7) wet manual sanding; (8) wet manual scraping.
Page 20 Health Hazard Evaluation Report No. 99–0113

2.4

3.7

4.4

4.4

012345678

Power finish sanding with bag

Dry manual sanding

Dry manual scraping

Power finish sanding

Flame burning

Power sanding with HEPA exhaust

Wet manual sanding

Wet manual scraping

Task

Hours

These tasks w ould not result in an estimated 8-hour 

TWA equal to the PEL at the 95% upper confidence 

limit (UCL) for the geometric mean exposure.

Figure 3. Average time performing task that would result in worker’s exposure reaching the PEL,

at 95% UCL for geometric mean.
Health Hazard Evaluation Report No. 99–0113 Page 21

-3

-2

-1

0

1

2

3

4

5

6

7

-5 0 5 10 15 20 25 30 35

R=0.30

Ln PbA

Paint Pb, %

Figure 4. Surface paint lead concentrations vs. natural log (Ln) personal PbA exposures for eight

renovation tasks, 128 PbA samples.
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