Evaluation of Lead 

Exposure at an 

Indoor Firing Range – 

California

Jessica G. Ramsey, MS, CPE

R. Todd Niemeier, MS, CIH

Health Hazard Evaluation Report

HETA 2008-0275-3146

November 2011 

DEPARTMENT OF HEALTH AND HUMAN SERVICES

Centers for Disease Control and Prevention

Workplace

Safety and Health

 National Institute for Occupational 

Safety and Health
The employer shall post a copy of this report 

for a period of 30 calendar days at or near 

the workplace(s) of affected employees. The 

employer shall take steps to insure that the 

posted determinations are not altered, defaced, 

or covered by other material during such 

period. [37 FR 23640, November 7, 1972, as 

amended at 45 FR 2653, January 14, 1980].
Health Hazard Evaluation Report 2008-0275-3146 Page i

Report Abbreviations................................................................................................ii

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

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

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

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

Assessment.....................................................................................................3

Results..............................................................................................................4

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

Conclusions................................................................................................. 10

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

References.................................................................................................... 16

Contents

Acknowledgments

Acknowledgments and Availability of Report................................ 31

Appendix A

Methods........................................................................................................ 17

Appendix B

Occupational Exposure Limits and Health Effects......................... 19

Appendix C

Tables............................................................................................................. 24
Page ii Health Hazard Evaluation Report 2008-0275-3146

Abbreviations

cm Centimeter

cm2 Square centimeter

μg/cm2 Micrograms per square centimeter

μg/dL Micrograms per deciliter

μg/m3 Micrograms per cubic meter

μm Micrometer

mm Millimeter

ACGIH® American Conference of Governmental Industrial Hygienists

AIHA American Industrial Hygiene Association

APF Assigned protection factor

AL Action level

BLL Blood lead level

CDC Centers for Disease Control and Prevention

CFR Code of Federal Regulations

CSTE Council of State and Territorial Epidemiologists

dB Decibel

DHHS Department of Health and Human Services

FOH Federal Occupational Health

fpm Feet per minute

HEPA High-efficiency particulate air

HHE Health hazard evaluation

Hz Hertz

Lpm Liters per minute

MDC Minimum detectable concentration

MERV Minimum efficiency reporting value

MQC Minimum quantifiable concentration

NAICS North American Industry Classification System

ND Not detected

NIOSH National Institute for Occupational Safety and Health

OEL Occupational exposure limit

OSHA Occupational Safety and Health Administration

PAPR Powered air purifying respirator

PBZ Personal breathing zone

PPE Personal protective equipment

PEL Permissible exposure limit

REL Recommended exposure limit

STEL Short-term exposure limit

TLV® Threshold limit value

TWA Time-weighted average

WEELTM Workplace environmental exposure level

ZPP Zinc protoporphyrin
Health Hazard Evaluation Report 2008-0275-3146 Page iii

The National Institute for 

Occupational Safety and 

Health (NIOSH) received 

a request for a health 

hazard evaluation at an 

indoor firing range in 

California. Employees 

submitted the request 

because they were 

concerned about lead 

exposures and indoor 

environmental quality 

problems during firearms 

instruction.

Highlights of the

NIOSH Health

Hazard Evaluation

What NIOSH Did

● We evaluated the firing range in January 2009 and again in 

December 2009.

● We looked at the ventilation systems. We also measured 

airflow in each bay of the firing range.

● We collected personal breathing zone air samples for lead on 

instructors, shooters, and the hazardous materials technician 

at the firing range.

● We collected area air samples for lead in the firing range, 

firearm cleaning area, classroom, lunchroom, and offices.

● We collected floor vacuum samples for lead. Samples were 

taken from rugs and carpet at the entrance to the firing range 

and in the firearm cleaning area, lunchroom, armory, and 

offices.

● We collected surface wipe samples for lead in various 

locations. We sampled areas in the firing range, firearm 

cleaning area, classroom, lunchroom, armory, and offices.

● We reviewed medical monitoring results of instructors and 

the hazardous materials technician.

What NIOSH Found

● Airflow along and downrange of the firing line did not meet 

the NIOSH recommendations.

● The firing range was dry swept during cleaning.

● Exposures for one instructor, one shooter, and the hazardous 

materials technician were above the occupational exposure 

limits for lead for an 8-hour time-weighted average.

● Another shooter’s exposure was above the Occupational 

Safety and Health Administration (OSHA) action level.

● Low concentrations of lead were found in area air samples 

from the firing range and firearm cleaning area.

● Surface wipe and floor vacuum samples detected lead in 

various places around the facility.

● Two instructors had threshold shifts that meet the NIOSH 

definition. Four instructors had slightly more hearing loss in 

the left ear than the right ear.
Page iv Health Hazard Evaluation Report 2008-0275-3146

What Managers Can Do

● Install a ventilation system that that can deliver the NIOSHrecommended airflow at the firing line and downrange.

● Do not dry sweep the firing range. Clean the floor with 

an explosion-proof vacuum cleaner with high-efficiency 

particulate air filters.

● Conduct periodic air sampling. This information will help 

evaluate whether changes made to the ventilation system and 

administrative practices have changed lead exposures.

● Remove all carpet in the facility.

● Improve general housekeeping practices, especially in the 

lunchroom, classroom, and office areas.

● Continue to do medical monitoring. Make sure these 

activities are done in accordance with the OSHA lead 

standard.

What Employees Can Do

● Instructors should refrain from using firearms on their 

workdays.

● Continue to wear dual hearing protection while in the 

firing range. Dual hearing protection includes ear plugs and 

earmuffs.

● Wash hands, arms, and face before eating, drinking, or 

touching others.

● Wear chemical-resistant gloves and tight-fitting goggles when 

cleaning firearms to protect your skin and eyes from potential 

chemical hazards.

● Change clothes and shoes before leaving the facility. When 

possible, also shower before leaving the facility.

● Wash clothes worn in the firing range separately from your 

family’s clothes.

● Report any health concerns to your employer. If needed, seek 

medical care.

Highlights of the

NIOSH Health

Hazard Evaluation

 (continued)
NIOSH evaluated lead 

exposures among 

instructors, shooters, and 

the hazardous materials 

technician at an indoor 

firing range. We found 

that some exposures 

exceeded applicable 

OELs. We also found 

lead on work surfaces 

throughout the facility. 

Recommendations for 

reducing the risk of 

lead exposure include 

installing a new ventilation 

system that meets NIOSH 

recommendations for 

airflow, eliminating dry 

sweeping, and improving 

housekeeping practices.

Summary

Health Hazard Evaluation Report 2008-0275-3146 Page v

In August 2008, NIOSH received an HHE request from employees 

at an indoor small arms firing range concerned about lead 

exposure and indoor environmental quality. We met with employer 

and employee representatives and observed work processes, 

practices, and workplace conditions on January 12–13, 2009. We 

also evaluated the ventilation systems, measured airflow in the 

firing range, and spoke with employees. On the basis of this initial 

visit, we recommended installing a new ventilation system capable 

of delivering the NIOSH-recommended airflow.

The follow-up site visit to collect air and surface lead samples was 

scheduled for March 2009; however, we delayed this site visit until 

December 2009 because of plans to install a new ventilation system 

in the firing range. This renovation was still delayed by the time 

of the December site visit, so we offered instead to collect air and 

surface samples to assess lead exposure before and after installation 

of the new ventilation system. This report only describes 

conditions before installation of the new ventilation system.

On December 8–10, 2009, we collected PBZ air samples on 

firing range instructors (instructors), shooters, and the hazardous 

materials technician at the facility. General area air samples, floor 

vacuum samples, and surface wipe samples were collected in areas 

around the facility. We also repeated the airflow measurements in 

the firing range.

The lead concentrations from PBZ air sampling on instructors 

ranged from ND–96 μg/m3 over the sampling period (calculated 

8-hour TWAs were ND–83 μg/m3); one instructor’s calculated 

TWA exposure (83 μg/m3) exceeded applicable OELs for an 

8-hour TWA. For shooters, PBZ lead exposures ranged from 

42–340 μg/m3 over the sampling periods (calculated 8-hour 

TWAs were 10–99 μg/m3). One shooter who repeated a portion 

of the qualification had an exposure of 99 μg/m3; this exceeded 

applicable OELs for an 8-hour TWA. The hazardous materials 

technician’s lead exposure was 3,200 μg/m3 over the sampling 

period (calculated 8-hour TWA was 670 μg/m3), exceeding the 

applicable OELs for an 8-hour TWA. The PBZ air sample was 

collected outside the loose-fitting PAPR that the hazardous 

materials technician wore while sweeping, vacuuming, and 

changing exhaust air vent filters in the firing range.
Page vi Health Hazard Evaluation Report 2008-0275-3146

Floor vacuum and surface wipe sample results showed the 

presence of lead on work surfaces. This suggests that workplace 

contamination was being tracked into these areas by employees’ 

footwear, clothing, or hands.

Our review of the instructors’ medical monitoring results indicated 

that BLLs were all below 10 μg/dL of lead. While reviewing 

medical records, we noted that four instructors had slightly more 

hearing loss in the left ear than the right ear. Two instructors had 

threshold shifts that met the NIOSH definition of 15 dB or more 

at any testing frequency.

In addition to our previous recommendation for a new ventilation 

system, we recommended eliminating dry sweeping, removing 

carpeting, and improving general housekeeping practices. We also 

recommended that instructors not use firearms on their workdays 

and that all personnel working in the firing range wash their 

hands, arms, and face before eating, drinking, or touching others. 

Periodic air sampling for lead should be performed whenever 

changes are made that affect instructor, shooter, or hazardous 

materials technician exposures. Management should also continue 

medical monitoring for personnel at the facility.

Keywords: NAICS 928110 (National Security), lead, CAS# 7439-

92-1, Indoor Environmental Quality, IEQ, indoor firing range

Summary

 (continued)
Health Hazard Evaluation Report 2008-0275-3146 Page 1

Introduction

NIOSH received an HHE request from employees concerning lead 

exposure and indoor environmental quality at an indoor firing 

range in California. NIOSH investigators conducted an initial 

site visit on January 12–13, 2009. During the site visit we met 

with employer and employee representatives to discuss the HHE 

request. We looked at the ventilation systems and measured airflow 

in the firing range. After the visit, we sent a letter summarizing 

our findings and providing recommendations for reducing lead 

exposure at the facility.

We planned to make a follow-up visit to collect air and surface lead 

samples in March 2009. During a phone conversation we learned 

that funds for a new ventilation system had been requested. The 

follow-up visit was postponed until a firm decision was made about 

funding for the new system. In a subsequent phone call in October 

2009, we learned that the ventilation system upgrade still had not 

begun. At that time, we offered to collect air and surface samples 

to assess lead exposure before and after installation of the new 

ventilation system.

We returned to the site on December 8–10, 2009, to assess the 

lead exposure before the new ventilation system was installed. We 

collected PBZ air samples, general area air samples, and surface 

wipe samples for lead. Preliminary findings and recommendations 

were provided in letters sent in June 2010. 

Background

The facility was located in a one-story building that consisted 

of the actual firing range and other spaces including multiple 

offices and cubicles, lunchroom, classroom, tactical hand-to-hand 

combat training areas, a firearms cleaning area, and an armory. 

The firing range had four bays; three bays were used for firearms 

qualifications, and the fourth bay was constructed as a mockup of 

a building interior for 360° live fire during Special Weapons and 

Tactics training. The three bays used for firearms qualifications 

had eight firing lanes in each bay. Firing lanes were fitted with a 

swinging arm rest during the January 2009 site visit, but these were 

not used during qualifications and had been removed by the time 

of the December 2009 site visit.

The firing range had three ventilation units serving the main 

section of the range. The ventilation systems for the firing range 

were separate from the rest of the facility and were designed so 

air traveled from uprange to downrange (from contaminated 
Page 2 Health Hazard Evaluation Report 2008-0275-3146

Background

 (continued) to less contaminated areas). Supply air was provided through a 

perforated metal wall plenum (Figure 1) located approximately 16 

feet behind the firing line, except near the entry door where it was 

approximately 10 feet away (Figure 2).

Two sets of return air vents were located downrange. The first set 

was approximately 36 feet from the firing line at the ceiling at a 

height of approximately 10 feet. The second set of vents was behind 

the bullet trap. Each vent contained MERV 8 Pre Pleat Model 40 

Standard Pleated Air Filters. The hazardous materials technician 

explained that a higher MERV-rated filter was too restrictive and 

resulted in low exhaust air flow and ventilation system malfunction.

Figure 1. Perforated metal wall plenum 

and the firing range safety 

officer’s station

Figure 2. Perforated metal wall 

plenum near the firing range 

entry door.
Health Hazard Evaluation Report 2008-0275-3146 Page 3

Assessment

During the January and December 2009 site visits, we measured 

the rate of airflow in different areas of the firing range. This 

included measurements at the firing line, below the first set of 

exhaust air vents, and at the bullet trap. We also noted during 

both site visits that the firing range was under negative pressure, as 

desired, in relation to the rest of the facility through the doorway 

separating these two areas.

During the December 2009 site visit, PBZ air samples for lead were 

collected on instructors, shooters, and the hazardous materials 

technician. PBZ air sampling for lead on instructors and shooters 

was conducted over two days. On December 8, 2009, 20 shooters 

were qualifying in lanes 5 through 24, and on December 9, 2009, 

13 shooters were qualifying in lanes 9 through 21. PBZ air samples 

were collected on all instructors and on various shooters depending 

on their lane assignment.

Instructors and shooters were required to wear ear plugs, earmuffs, 

bulletproof vests, and safety glasses during qualifications. The 

shooters performed a pistol qualification (72 rounds), a shotgun 

qualification (5 slugs), a shotgun familiarization (25 rounds of 

birdshot), and a night pistol practical (48 rounds). Qualifications 

required both standing and kneeling positions. The total time for 

all the firearm qualifications was approximately 1 hour. During 

the firing exercises, the targets were controlled with a pulley system 

so the shooters did not have to cross the firing line. However, 

they did cross the line to clean up spent ammunition casings after 

qualifications were completed. After the qualification exercises, 

shooters cleaned their firearms for approximately 20 minutes in a 

cleaning area between the firing range and the classroom area. PBZ 

air samples were collected on shooters during qualifications and 

firearm cleaning. Instructors’ tasks were varied. If instructors gave 

the morning lecture, they did not participate in qualifications. If 

they observed qualifications they also sometimes fired rounds of 

ammunition.

We collected PBZ air samples on the hazardous materials 

technician on December 8 and December 9, 2009. The hazardous 

materials technician was responsible for daily firing range cleanup. 

This included removal of lead-contaminated debris and dust from 

the firing range. The hazardous materials technician cleaned the 

range each morning before qualifications, Monday through Friday. 

This included dry sweeping the range with a push broom, and then 

vacuuming the range with a Nilfisk GM80 HEPA vacuum. This 
Page 4 Health Hazard Evaluation Report 2008-0275-3146

Assessment

 (continued)

Results

procedure was repeated in the space behind the bullet trap. The 

hazardous materials technician was also responsible for changing 

the exhaust air vent filters in the firing range and behind the bullet 

trap (usually three times per week), as well as emptying the bullet 

trap trough as needed (usually twice per week). The hazardous 

materials technician wore two pairs of disposable coveralls, butyl 

rubber gloves, and a loose-fitting PAPR respirator during firing 

range cleaning and filter change activities. He donned the PPE 

in the trailer outside the facility. He doffed the outside coveralls 

inside the back or front of the firing range depending on where he 

was working. Before he exited the shooting area he wet wiped his 

PAPR and stepped into the non-shooting area of the range where 

he doffed the inside coveralls and removed his respirator.

Other lead sampling conducted on December 8–10, 2009, 

included general area air samples, floor vacuum samples, and 

surface wipe samples. General area air samples were collected in 

the firing range, firearm cleaning area, classroom, lunchroom, 

and offices. Floor vacuum samples for lead content from rugs 

and carpet were collected in various locations around the facility. 

Surface wipe samples for lead were collected from various 

horizontal surfaces around the facility.

Details on the methods for the ventilation system evaluation, 

as well as air, surface, and vacuum sampling are presented in 

Appendix A. A discussion of OELs and potential health effects is 

presented in Appendix B.

We also reviewed medical monitoring results including BLL, ZPP 

levels, and audiograms performed on instructors from 2007–2011. 

This monitoring was performed by FOH, under contract with the 

facility. Annual testing is required per the OSHA lead standard; 

however FOH is available on-site twice a year in case instructors are 

on leave one of the two days.

A summary of the ventilation flow rate measurements is provided 

in Table 1. Airflow along the firing line did not meet the NIOSHrecommended minimum airflow of 50 fpm [NIOSH 2009]. 

Some of the downrange measures met the NIOSH-recommended 

minimum airflow of 30 fpm [NIOSH 2009]. The tables in 

Appendix C provide the air flow rates at specific areas along the 

firing line in each lane. Tables C1, C2, and C3 provide the supply 

airflow measurement data that we collected in January 2009 in 
Health Hazard Evaluation Report 2008-0275-3146 Page 5

Results

 (continued) each of the three bays used for firearms qualifications. Tables C4, 

C5, and C6 provide the supply airflow measurement data collected 

in the same areas in December 2009.

Table 1. Summary of ventilation measurements (fpm) in each bay used for firearms qualification

Firing Downrange

Date Location Line First Exhaust Air 

Vent Bullet Trap

Bay 1: Lanes 1–8 37 27 21

January 2009 Bay 2: Lanes 9–16 45 36 18

Bay 3: Lanes 17–24 38 36 22

Bay 1: Lanes 1–8 48 14 14

December 2009 Bay 2: Lanes 9–16 36 24 23

Bay 3: Lanes 17–24 44 38 24

Individual results of the PBZ air sampling for lead on instructors 

and shooters are presented in Appendix C, Tables C7 and C8. 

A summary of these results is shown in Table 2. The instructors’ 

lead concentrations ranged from ND–96 μg/m3 over the sampling 

period (86–416 minutes). We did not collect PBZ air samples on 

instructors during their other work activities outside of the range; 

however, general area air samples taken in the staff office and 

lunchroom were ND (Table C9). Assuming that the instructors 

received no further exposure to airborne lead during that work 

shift, these results equate to 8-hour TWAs ranging from ND–83 

μg/m3. One instructor’s exposure (83 μg/m3) exceeded the OELs of 

50 μg/m3 for an 8-hour TWA. Under the OSHA general industry 

lead standard (29 CFR 1910.1025), the PEL for airborne exposure 

to lead is 50 μg/m3 for an 8-hour TWA. The NIOSH REL and 

ACGIH TLV are also 50 μg/m3 for an 8-hour TWA [NIOSH 2010; 

ACGIH 2011].

Table 2. Concentrations of lead on PBZ air samples of instructors, shooters, and the hazardous materials 

technician

Title Sample Time 

(minutes)

Sample 

Concentration (μg/m3)

8-hour TWA 

Concentration (μg/m3)

Instructors 86–416 ND*–96 ND–83†

Shooters 102–145 42–340 10–99†

Hazardous materials technician 101 3,200 670†

*ND = not detected; below the MDC (0.61 μg/m3)

†Exceeds the OSHA PEL of 50 μg/m3 for an 8-hour TWA; assumes no exposure for unsampled time during the 

work shift.
Page 6 Health Hazard Evaluation Report 2008-0275-3146

The shooters’ lead concentrations ranged from 42–340 μg/m3 over 

the sampling periods (102–145 minutes). We did not collect PBZ 

air samples on shooters during their classroom time; however, a 

general area air sample taken in the classroom was ND (Table C9). 

After the shooters completed the qualifications, they left the firing 

range facility. Assuming the shooters received no further exposure 

to airborne lead during the day, these results equate to 8-hour 

TWAs ranging from 10–99 μg/m3.

The result of the PBZ air sampling for lead on the hazardous 

materials technician is presented in Table 2. Assuming no other 

lead exposure, this hazardous materials technician’s 8-hour TWA 

lead exposure of 670 μg/m3 exceeds the OELs.

Results of the general area air sampling for lead are presented in 

Table C9 (Appendix C). The lead concentrations ranged from 

ND–3.6 μg/m3. Most results were ND or at a concentration 

between the MDC and the MQC.

Floor vacuum sample results are presented in Table C10 (Appendix 

C), and surface wipe sample results are presented in Table C11 

(Appendix C). The range of sampling results is shown in Table 3. 

These results showed the presence of lead on work surfaces outside 

of the range.

Results

 (continued)

Table 3. Concentrations of lead in floor vacuum and surface wipe 

samples

Sample Type Sample Concentration (μg/cm2)

Floor vacuum 0.025–0.31

Surface wipe ND*–2.0

*ND = not detected; below the MDC (0.004 μg/cm2).

A summary of the medical monitoring results, obtained from 

FOH, indicated that instructors’ BLLs ranged from < 3–6 μg/dL 

and ZPP levels ranged from 28–56 μg/dL. A full table of results 

is presented in Table C12 (Appendix C). FOH also provided 

audiograms for nine instructors who worked at the facility from 

2007–2011. It was noted that four employees had slightly more 

hearing loss in the left ear than the right ear. Only five instructors 

had multiple audiograms to compare for threshold shifts; of 

these two had threshold shifts that met the NIOSH definition of 

15 dB or more at any testing frequency. The occupational medicine 

department of the Naval Training Center provided medical 

monitoring results for the hazardous materials technician. BLLs for 

the hazardous materials technician were all at or below 12 μg/dL, 

and ZPP levels were in the same range as those for instructors.
Health Hazard Evaluation Report 2008-0275-3146 Page 7

Discussion

In 2009, NIOSH issued recommendations on occupational 

exposure to lead and noise in firing ranges [NIOSH 2009]. The 

design we evaluated in 2009 did not meet many of the NIOSH 

recommendations for ventilation design. Most notably, our 

ventilation measurements indicated that airflow along the firing 

line in all three bays used for firearms qualifications did not meet 

the NIOSH-recommended minimum airflow of 50 fpm along the 

firing line. Many of our downrange measures at both the midrange 

exhaust air vent and bullet trap were also below the NIOSHrecommended downrange minimum airflow of 30 fpm. During 

our January 2009 site visit, we observed numerous obstructions 

including garbage cans, placards, tables, and casing sweepers along 

the perforated wall supply air plenum. These obstructions reduced 

uniform air flow across the firing line. We noted during our 

December 2009 site visit that some of the obstructions had been 

removed; however, other obstructions remained. Additionally, the 

range safety officer’s station blocked the perforated wall supply air 

plenum in front of several firing lanes in Bays 2 and 3.

We collected PBZ air samples on instructors during their 

normal shifts on December 8 and 9, 2009. The results of this 

evaluation indicate that most instructors had lead exposures 

that were well below OELs. However, one instructor’s exposure 

exceeded the lead OELs on December 9, 2009. This instructor 

observed qualifications (similar to other instructors) but also fired 

approximately 55 rounds of shotgun ammunition during the work 

shift. This was not typical; however, some instructors did fire their 

own guns or other guns on various days.

We collected PBZ air samples on shooters while they were 

performing firearms qualifications and cleaning their firearms. 

Overall, sampling results for lead for shooters were much 

higher over the sampling period as compared to instructors. 

However, because qualification and firearms cleaning only lasted 

approximately 2–3 hours, most of the shooters’ exposures were 

below 8-hour TWA OELs for lead. However, one shooter’s 

exposure (an 8-hour TWA exposure, 99 μg/m3) was almost two 

times greater than the OELs for lead on December 8, 2009. This 

shooter returned to the firing range during the lunch break to 

repeat some of the qualifications. Another shooter had an 8-hour 

TWA of 32 μg/m3, which is above the OSHA AL of 30 μg/m3. 

This shooter was positioned in Lane 16 on December 8, 2009. The 

ventilation flow rate measurement at Lane 16 during the December 

site visit was 13 fpm (at 5-foot height), which was the lowest flow 
Page 8 Health Hazard Evaluation Report 2008-0275-3146

rate measured along the firing line. The airflow for Lane 16 may 

have been obstructed by the range safety officer’s station.

The PBZ sample collected on the hazardous materials technician 

on December 9, 2009, was collected outside the loose-fitting PAPR 

that he wore during all work activities cleaning the firing range. 

The hazardous materials technician’s lead exposure collected in 

this sample was greater than 13 times the OELs for lead. In this 

instance a maximum use concentration for lead over a workday can 

be calculated by multiplying the loose-fitting PAPR APF (25) and 

the lead OEL (50 μg/m3), equaling 1250 μg/m3. If it is assumed 

the hazardous materials technician had an 8-hour TWA exposure 

of 670 μg/m3 (which is below the maximum use concentration of 

1250 μg/m3), the loose-fitting PAPR should be protective under 

these conditions. However, the hazardous materials technician 

only worked 101 minutes on December 9, 2009. The exposure 

over this shorter time period is 3,200 μg/m3, a concentration that 

exceeds the maximum use concentration for a loose-fitting PAPR. 

Therefore, further reductions in exposure are needed. This very 

high exposure is likely due to dry sweeping instead of vacuuming 

the firing range floor. The hazardous materials technician preferred 

sweeping because the firing range vacuum would not remove the 

larger cardboard pieces that fell to the floor from targets following 

qualifications. Dry sweeping is not recommended. The hazardous 

materials technician informed us that he changed the filter on the 

HEPA vacuum approximately twice a year and changed the bag in 

the vacuum about once a month.

Airborne lead was detected in very low concentrations in the 

firing range (at the range safety officer’s station) and firearm 

cleaning area (between 0.61 μg/m3 and 1.9 μg/m3). However, 

because airborne lead was detected in the firearm cleaning area 

this may have been leading to lead contamination in the office, 

classroom, and lunchroom areas because it was on the office side 

of the ventilation system. Lead from contaminated surfaces can 

be transferred to the skin, especially the hands. This can result in 

lead ingestion while handling food, beverages, and other items that 

contact the mouth.

Floor vacuum and surface wipe sample results showed the 

presence of lead on work surfaces. This suggests that workplace 

contamination could also be tracked into these areas by employees’ 

footwear, clothing, or hands. Carpeting, which was noted in 

the lunchroom and staff offices, is not recommended inside a 

Discussion

 (continued)
Health Hazard Evaluation Report 2008-0275-3146 Page 9

firing range or in rooms adjacent to the range [NIOSH 2009]. 

No occupational exposure guidelines or regulations exist for lead 

concentrations on work surfaces; however, lead-contaminated 

surfaces in the workplace represent a potential source of exposure 

for employees. OSHA specifies in its substance-specific standard 

for lead that all surfaces be maintained as free as practicable of 

accumulations of lead [29 CFR 1910.1025(h)(1)]. Our evaluation 

showed the highest amount of lead on the armory shelving unit 

and the top of the filing cabinet near the firearm cleaning area. 

These two locations are probably rarely cleaned. However, lead was 

also detected on the top of the modular cabinet in the lunchroom 

and in the office areas; this indicates that general cleaning needs to 

be improved throughout the facility.

OSHA’s lead standard requires each employer who operates a 

firing range to determine if any workers may be exposed to lead at 

or above the AL (30 μg/m3 as an 8-hour TWA). Worker exposure 

is defined as exposure that would occur if the workers were not 

using a respirator. On the basis of our air sampling, instructors, 

shooters, and the hazardous materials technician may be exposed at 

the AL, and therefore monitoring their exposure to lead should be 

performed periodically to ensure continued effectiveness of current 

protection measures. Additionally, any changes in work practices, 

equipment, or maintenance procedures would also trigger a need 

for air sampling.

Because some airborne exposures to lead were identified above the 

OSHA PEL, the facility should follow OSHA lead regulations to 

prevent spread of lead contamination outside of the workplace. 

The regulations (29 CFR 1910.1025) include mandating that 

employees take showers before leaving the facility and providing 

locker space to ensure that street clothes are not contaminated with 

lead dust.

The OSHA lead standard also requires participation in a 

medical clearance program for lead. Currently, instructors and 

the hazardous materials technician undergo annual medical 

monitoring. Our review showed that monitoring results for 

instructors did not exceed the guideline of 10 μg/dL for 

BLL recommended by the Association of Occupational and 

Environmental Clinics [CSTE 2009]. However, the hazardous 

materials technician exceeded this guideline on 3 occasions with 

levels up to 12 μg/dL. The hazardous materials technician also 

participated in a respiratory protection program that met the 

requirements of the OSHA respiratory protection standard.

Discussion

 (continued)
Page 10 Health Hazard Evaluation Report 2008-0275-3146

Discussion

 (continued)

Conclusions

Typically, workers with noise-induced hearing loss have an 

approximately equal loss in both ears. Our review of the 

audiograms for instructors showed more hearing loss in the left ear 

compared to the right ear. Asymmetrical hearing loss is known to 

occur in shooters [Prosser et al. 1988; Sataloff and Sataloff 2006] 

and is thought to be related to the person’s head position when 

using firearms such as rifles or shotguns. Right-handed shooters 

are more likely to have hearing loss in their left ear and left-handed 

shooters tend to have more hearing loss in their right ear. Although 

asymmetric hearing loss is more common in shooters than other 

workers exposed to noise, instructors should be evaluated by an 

audiologist or ear, nose, and throat specialist to rule out other 

medical causes for asymmetric loss.

NIOSH defines a hearing threshold shift as a 15-dB change in 

hearing threshold in any of the audiometric test frequencies. 

Analysis of the audiograms was limited because several of the 

instructors only had one or two audiograms available for review. 

However, of those that we were able to compare, most of the shifts 

were at 4,000 Hz and 6,000 Hz and differences ranged between 

15 dB and 50 dB.

The results of this evaluation indicated that instructors, shooters, 

and the hazardous materials technician were exposed to lead 

above the OELs. In particular, instructors were found to have 

higher exposure to lead if they used firearms on the days that 

they observed qualifications. Shooters were found to have higher 

exposure to lead if they returned to the firing range for additional 

rounds of shooting. The hazardous materials technician was 

found to have high levels of exposure to lead which we believe is 

due to dry sweeping the firing range. Floor vacuum and surface 

wipe sample results showed the presence of lead on work surfaces 

throughout the facility. This suggests that workplace contamination 

is being tracked into these areas by employees’ footwear, 

clothing, or hands. Engineering and administrative controls are 

recommended to reduce exposures.
Health Hazard Evaluation Report 2008-0275-3146 Page 11

Recommendations

On the basis of our findings, we recommend the actions listed 

below to create a more healthful workplace. We encourage 

the firing range to use a labor-management health and safety 

committee or working group to discuss the recommendations 

in this report and develop an action plan. Those involved in 

the work can best set priorities and assess the feasibility of our 

recommendations for the specific situation at the facility. Our 

recommendations are based on the hierarchy of controls approach 

(refer to Appendix B: Occupational Exposure Limits and Health 

Effects). This approach groups actions by their likely effectiveness 

in reducing or removing hazards. In most cases, the preferred 

approach is to eliminate hazardous materials or processes and 

install engineering controls to reduce exposure or shield employees. 

Until such controls are in place, or if they are not effective or 

feasible, administrative measures and/or personal protective 

equipment may be needed. Most of these recommendations were 

taken from the NIOSH Alert, “Preventing Occupational Exposures 

to Lead and Noise at Indoor Firing Ranges” [NIOSH 2009].

Elimination and Substitution

Elimination or substitution of a toxic/hazardous process material 

is a highly effective means for reducing hazards. Incorporating 

this strategy into the design or development phase of a project, 

commonly referred to, as “prevention through design,” is most 

effective because it reduces the need for additional controls in the 

future.

1. Use non-lead primers designed specifically for firing ranges. 

Cartridges already loaded with non-lead primers are 

commercially available for the most popular calibers.

2. Investigate the use of electronic simulation systems using 

firearms equipped with lasers, which can provide an alternative 

solution for training new recruits in effective firearm handling 

and marksmanship without using live ammunition.

Engineering Controls

Engineering controls reduce exposures to employees by removing 

the hazard from the process or placing a barrier between the 

hazard and the employee. Engineering controls are very effective 

at protecting employees without placing primary responsibility of 

implementation on the employee.
Page 12 Health Hazard Evaluation Report 2008-0275-3146

Recommendations

 (continued) 1. Install a ventilation system capable of delivering the NIOSHrecommended airflow at the firing line and downrange. Airflow 

along the firing line should be no more than 75 fpm with a 

minimum acceptable flow of 50 fpm. To minimize fallout of 

firearm emissions downrange of the firing line (if desired), 

downrange airflow should be maintained at a minimum of 30 

fpm and should be evenly distributed.

2. Enclose the firearm cleaning area, as airborne lead was detected 

in this area. This will help to reduce the spread of airborne 

lead contamination to other areas of the building. Assistance 

of a contractor familiar with firing range design is strongly 

encouraged.

3. Remove objects (e.g., cabinets, tables, placards, brass collectors, 

and garbage cans) obstructing airflow between the supply air 

inlets and the firing line so that the supply air is distributed 

uniformly across the width of the firing range.

4. Use HEPA filters or filters with a MERV rating of 18–19 in the 

exhaust ventilation system.

5. Change filters according to the static pressure guidelines 

provided by the manufacturer. Filter end-of-service life is 

indicated by a high-pressure drop across the filter bank. Because 

pre-filters are the first to encounter contaminated exhaust air 

from the firing range, they will load fastest. Therefore, pre-filters 

require more frequent change-outs than high efficiency filters.

Administrative Controls

Administrative controls are management-dictated work practices 

and policies to reduce or prevent exposures to workplace hazards. 

The effectiveness of administrative changes in work practices 

for controlling workplace hazards is dependent on management 

commitment and employee acceptance. Regular monitoring and 

reinforcement are necessary to ensure that control policies and 

procedures are not circumvented in the name of convenience or 

production.

1. Advise instructors to refrain from using firearms on their 

workdays. If instructors need to use firearms on days when they 

are observing qualifications, then respiratory protection may 

be necessary. Confirm these exposures with additional PBZ air 

sampling.
Health Hazard Evaluation Report 2008-0275-3146 Page 13

2. Clean the floor of the firing range thoroughly with an explosionproof HEPA vacuum cleaner designed to collect lead dust. Dry 

sweeping should never be used in the firing range. The OSHA 

general industry lead standard [29 CFR 1910.1025(h)(2)(ii)] 

states that shoveling, dry or wet sweeping, and brushing may be 

used only where vacuuming or other equally effective methods 

have been tried and found ineffective.

3. All personnel should wash their hands, forearms, and faces 

before eating, drinking, or having any hand contact with the face 

or with other people.

4. Avoid skin contact with spent cartridges whenever possible. 

Wear disposable gloves should when removing larger objects that 

cannot be removed with a HEPA vacuum cleaner.

5. Clean floor and horizontal surfaces inside the firing range 

routinely with a detergent. U.S. Environmental Protection 

Agency studies show that general all-purpose cleaners are 

adequate for both general cleaning and post-intervention 

cleaning.

6. Remove carpeting in rooms adjacent to the firing range. 

Accumulation of lead dust in carpets is a health hazard, and 

accumulation of unspent primer in carpets is a fire hazard.

7. Improve general housekeeping practices throughout the facility 

to keep horizontal surfaces free of dust and debris. Lunchroom, 

classroom, and office areas should receive special attention 

because of the potential for lead exposure through hand-tomouth contact. Detergents that contain trisodium phosphate are 

best for cleaning surfaces that may have lead contamination.

8. Advise shooters who use a kneeling position on lead 

contaminated surfaces to place a sheet of paper or other 

disposable material on the ground beneath them to minimize 

accumulation of leaded dust on their outer garments.

9. Instruct shooters and instructors to shower, whenever possible, 

and change clothes at the facility after shooting or performing 

maintenance or cleaning activities in the firing range. Clothes 

worn at the firing range should be washed separately from 

family’s clothes.

10. Provide clean change rooms for employees who work in areas 

where there is airborne exposure to lead. Also provide workers 

with two lockers to allow them to separate street clothes from 

lead-contaminated work clothes.

Recommendations

 (continued)
Page 14 Health Hazard Evaluation Report 2008-0275-3146

11. Leave shoes worn on the firing range at the range or bag them 

before leaving the range to prevent lead from being tracked 

into cars and onto home floors and carpets. As an alternative, 

use step-off cleaning pads at the exit of the firing range to help 

reduce the amount of lead contamination on shoes. Disposable 

shoe coverings can also be used while firing and cleaning, then 

discarded upon leaving the range.

Worker Exposure and Medical Health 

Monitoring

Instructors and the hazardous materials technician had medical 

monitoring performed annually. Our results indicate that 

instructors, shooters, and the hazardous materials technician may 

be exposed above the OSHA AL for lead; therefore, the following 

recommendations are provided.

1. Perform periodic air sampling for lead whenever changes are 

made that affect instructor, shooter, or hazardous materials 

technician exposures. If instructors or shooters continue to have 

exposures above the OELs due to increased time spent using 

firearms, then respiratory protection would be required. Once 

dry sweeping is eliminated and a new cleaning procedure is in 

place, repeat air sampling on the hazardous materials technician 

to determine exposure levels and what level of respiratory 

protection is needed.

2. Conduct air sampling under the direction of a certified 

industrial hygienist or other safety and health professional with 

appropriate training and expertise.

3. Perform wipe sampling regularly on surfaces in the firing range. 

Wipe samples can provide information about how well these 

surfaces are being cleaned, whether lead is being transported 

from the firing range to other parts of the facility, and about the 

potential for lead exposure.

4. Follow the OSHA general industry lead standard, which 

contains provisions for the medical monitoring of workers 

exposed to lead [29 CFR 1910.1025(j)]. NIOSH supports using 

these provisions for firing range workers.

Recommendations

 (continued)
Health Hazard Evaluation Report 2008-0275-3146 Page 15

5. Report any symptoms consistent with lead exposure in adults 

to the employer or firing range safety officer. Common 

symptoms of lead poisoning in adults include nausea, diarrhea, 

vomiting, poor appetite, weight loss, anemia, excess lethargy or 

hyperactivity, headaches, abdominal pain, and kidney problems.

Personal Protective Equipment

PPE is the least effective means for controlling employee exposures. 

Proper use of PPE requires a comprehensive program, and calls 

for a high level of employee involvement and commitment to be 

effective. The use of PPE requires the choice of the appropriate 

equipment to reduce the hazard and the development of 

supporting programs such as training, change-out schedules, and 

medical assessment if needed. PPE should not be relied upon as 

the sole method for limiting employee exposures. Rather, PPE 

should be used until engineering and administrative controls can 

be demonstrated to be effective in limiting exposures to acceptable 

levels.

1. Encourage personnel cleaning firearms to use chemical-resistant 

gloves and tight-fitting goggles for skin and eye protection against 

potential chemical hazards. Firing range operators should 

provide specific guidance about proper and appropriate use of 

skin and eye protection.

2. Select respirators based on their APF, considering the PBZ lead 

exposures of instructors and the hazardous materials technician. 

Respirator type should be reconsidered whenever changes are 

made that affect exposures.

3. Continue to require instructors and shooters to wear dual 

hearing protection (ear plugs and earmuffs) while in the firing 

range. For maximum protection, select earmuffs and ear plugs 

that provide a high level of noise attenuation. To ensure that 

hearing protectors have adequate noise attenuation and are 

worn correctly, perform fit testing. Some hearing protection 

manufacturers are able to conduct hearing protection fit testing. 

Additionally, because of the critical importance of proper fit, the 

firing range safety officer should regularly check to ensure that 

hearing protection is worn correctly.

Recommendations

 (continued)
Page 16 Health Hazard Evaluation Report 2008-0275-3146

ACGIH [2011]. 2011 TLVs® and BEIs®: threshold limit values for 

chemical substances and physical agents and biological exposure 

indices. Cincinnati, OH: American Conference of Governmental 

Industrial Hygienists.

CSTE [2009]. Public health reporting and national notification 

for elevated blood lead levels. CSTE position statement 09-OH-02. 

Atlanta: CSTE 2009 [http://www.cste.org/ps2009/09-OH-02.pdf]. 

Date accessed: October 2011.

CFR. Code of Federal Regulations. Washington, DC: U.S. 

Government Printing Office, Federal Register.

NIOSH [2009]. NIOSH alert: preventing occupational exposures 

to lead and noise at indoor firing ranges. 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. 2009-136.

NIOSH [2010]. NIOSH pocket guide to chemical hazards. 

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. 2010-168c. [http://www.cdc.gov/niosh/npg/]. Date accessed: 

October 2011.

Prosser S, Tartari M, Arslan E [1988]. Hearing loss in sports 

hunters exposed to occupational noise. Br J Aud 22(2):85–91.

Sataloff R, Sataloff J [2006]. Occupational hearing loss. 3rd ed. 

Boca Raton, FL: Taylor and Francis Group, LLC, pp. 411–440.

References
Page 17

Ventilation Measurements

A TSI VelociCalc® Plus air velocity meter, model 8386A (TSI, Inc, Shoreview, Minnesota) was used to 

measure airflow at different locations within the firing range, including at the firing line, at the first set 

of exhaust air vents (located 36 feet downrange from the firing line), and at the bullet trap. Triplicate 

measurements were collected in each lane along the firing lane at two different heights (approximately 

3 feet and 5 feet). These measurements were averaged together and reported for each location along the 

firing lane.

Air Sampling for Lead

Air samples for lead were collected on 37-mm diameter, 0.8-μm pore size mixed cellulose ester filters using 

SKC Air Check® 2000 air sampling pumps (SKC, Inc, Eighty Four, Pennsylvania) calibrated at a flow rate 

of 2 Lpm. The inlet port of the sampling pump was connected to the sampling media with Tygon® tubing. 

For PBZ air samples, the sampling media was attached to the employee’s lapel within the breathing zone, 

roughly defined as an area in front of the shoulders with a radius of 6 to 9 inches. The general area air 

samples were placed throughout the facility including areas where instructors or shooters took breaks and 

ate lunch. Air samples were analyzed by inductively coupled argon plasma-atomic emission spectroscopy 

according to NIOSH Method 7303 [NIOSH 2011].

Surface Wipe Sampling for Lead

Surface wipe samples were collected with premoistened Palintest® Dust Wipes (Palintest USA, Erlanger, 

Kentucky) according to NIOSH Method 9102 [NIOSH 2011]. The collection procedure was as follows: (1) 

identify the area to be sampled; (2) put on a pair of disposable nitrile gloves; (3) place the wipe flat on the 

surface as defined by the 10 cm by 10 cm (100 cm2 area) disposable template and wipe the surface using 

three to four horizontal S-strokes, side-to-side so that the entire surface is covered; (4) fold the exposed 

side of the wipe in and wipe the area with three or four vertical S-strokes; (5) fold the wipe once more and 

wipe the area with three or four horizontal S-strokes; and (6) fold the pad, exposed side in, and place in a 

sterile container. A new template and a pair of disposable gloves were used for each surface wipe sample. 

The surface wipe samples were digested and analyzed by inductively coupled argon plasma-atomic emission 

spectroscopy according to NIOSH Method 9102 with modifications [NIOSH 2011].

Vacuum Sampling for Lead

Vacuum samples were collected on 37-mm diameter, 0.8-μm pore size mixed cellulose ester filters with 

small nozzle attachments connected to SKC Air Check® 2000 air sampling pumps (SKC, Inc, Eighty Four, 

Pennsylvania) calibrated at a flow rate of 2 Lpm. The surface was vacuumed in the same way other surfaces 

were wiped, three sets of S-curve wipes over a 100 cm2 area determined by a disposable template according 

to NIOSH Method 9102 [NIOSH 2011]. These samples were also analyzed by inductively coupled argon 

plasma-atomic emission spectroscopy according to NIOSH Method 7303 [NIOSH 2011].

Health Hazard Evaluation Report 2008-0275-3146

Appendix A: Methods
Page 18 Health Hazard Evaluation Report 2008-0275-3146

Appendix A: Methods 

 (continued)

Reference

NIOSH [2011]. NIOSH manual of analytical methods (NMAM®). 4th ed. Schlecht PC, O’Connor PF, 

eds. 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 94-113 

(August 1994); 1st Supplement Publication 96-135, 2nd Supplement Publication 98-119; 3rd Supplement 

2003-154. [http://www.cdc.gov/niosh/nmam/].
Page 19

In evaluating the hazards posed by workplace exposures, NIOSH investigators use both mandatory (legally 

enforceable) and recommended OELs for chemical, physical, and biological agents as a guide for making 

recommendations. OELs have been developed by federal agencies and safety and health organizations to 

prevent the occurrence of adverse health effects from workplace exposures. Generally, OELs suggest levels 

of exposure that most employees may be exposed to for up to 10 hours per day, 40 hours per week, for a 

working lifetime, without experiencing adverse health effects. However, not all employees will be protected 

from adverse health effects even if their exposures are maintained below these levels. A small percentage 

may experience adverse health effects because of individual susceptibility, a preexisting medical condition, 

and/or a hypersensitivity (allergy). In addition, some hazardous substances may act in combination with 

other workplace exposures, the general environment, or with medications or personal habits of the 

employee to produce adverse health effects even if the occupational exposures are controlled at the level set 

by the exposure limit. Also, some substances can be absorbed by direct contact with the skin and mucous 

membranes in addition to being inhaled, which contributes to the individual’s overall exposure.

Most OELs are expressed as a TWA exposure. A TWA refers to the average exposure during a normal 8- 

to 10-hour workday. Some chemical substances and physical agents have recommended STEL or ceiling 

values where adverse health effects are caused by exposures over a short period. Unless otherwise noted, 

the STEL is a 15-minute TWA exposure that should not be exceeded at any time during a workday, and 

the ceiling limit is an exposure that should not be exceeded at any time.

In the United States, OELs have been established by federal agencies, professional organizations, state 

and local governments, and other entities. Some OELs are legally enforceable limits, while others are 

recommendations. The U.S. Department of Labor OSHA PELs (29 CFR 1910 [general industry]; 29 

CFR 1926 [construction industry]; and 29 CFR 1917 [maritime industry]) are legal limits enforceable 

in workplaces covered under the Occupational Safety and Health Act of 1970. NIOSH RELs are 

recommendations based on a critical review of the scientific and technical information available on a 

given hazard and the adequacy of methods to identify and control the hazard. NIOSH RELs can be 

found in the NIOSH Pocket Guide to Chemical Hazards [NIOSH 2010]. NIOSH also recommends different 

types of risk management practices (e.g., engineering controls, safe work practices, employee education/

training, personal protective equipment, and exposure and medical monitoring) to minimize the risk of 

exposure and adverse health effects from these hazards. Other OELs that are commonly used and cited 

in the United States include the TLVs recommended by ACGIH, a professional organization, and the 

WEELs recommended by the American Industrial Hygiene Association, another professional organization. 

The TLVs and WEELs are developed by committee members of these associations from a review of the 

published, peer-reviewed literature. They are not consensus standards. ACGIH TLVs are considered 

voluntary exposure guidelines for use by industrial hygienists and others trained in this discipline “to assist 

in the control of health hazards” [ACGIH 2011]. WEELs have been established for some chemicals “when 

no other legal or authoritative limits exist” [AIHA 2011].

Outside the United States, OELs have been established by various agencies and organizations and 

include both legal and recommended limits. The Institut für Arbeitsschutz der Deutschen Gesetzlichen 

Unfallversicherung (IFA, Institute for Occupational Safety and Health of the German Social Accident 

Insurance) maintains a database of international OELs from European Union member states, Canada 

Health Hazard Evaluation Report 2008-0275-3146

Appendix B: Occupational Exposure Limits and Health Effects
Page 20 Health Hazard Evaluation Report 2008-0275-3146

(Québec), Japan, Switzerland, and the United States. The database, available at http://www.dguv.de/ifa/

en/gestis/limit_values/index.jsp, contains international limits for over 1,500 hazardous substances and is 

updated periodically.

Employers should understand that not all hazardous chemicals have specific OSHA PELs, and for some 

agents the legally enforceable and recommended limits may not reflect current health-based information. 

However, an employer is still required by OSHA to protect its employees from hazards even in the absence 

of a specific OSHA PEL. OSHA requires an employer to furnish employees a place of employment free 

from recognized hazards that cause 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))]. Thus, NIOSH investigators encourage 

employers to make use of other OELs when making risk assessments and risk management decisions to 

best protect the health of their employees. NIOSH investigators also encourage the use of the traditional 

hierarchy of controls approach to eliminate or minimize identified workplace hazards. This includes, in 

order of preference, the use of (1) substitution or elimination of the hazardous agent, (2) engineering 

controls (e.g., local exhaust ventilation, process enclosure, dilution ventilation), (3) administrative controls 

(e.g., limiting time of exposure, employee training, work practice changes, medical surveillance), and (4) 

personal protective equipment (e.g., respiratory protection, gloves, eye protection, hearing protection). 

Control banding, a qualitative risk assessment and risk management tool, is a complementary approach 

to protecting employee health that focuses resources on exposure controls by describing how a risk 

needs to be managed. Information on control banding is available at http://www.cdc.gov/niosh/topics/

ctrlbanding/. This approach can be applied in situations where OELs have not been established or can be 

used to supplement the OELs, when available.

Below we provide the OELs and surface contamination limits as well as a discussion of the potential 

health effects for exposure to lead.

Lead

Lead is ubiquitous in U.S. urban environments because of the widespread use of lead compounds in 

industry, gasoline, and paints during the past century. Exposure to lead occurs via inhalation of dust and 

fume and via ingestion through contact with lead-contaminated hands, food, cigarettes, and clothing. 

Absorbed lead accumulates in the body in the soft tissues and bones. Lead is stored in bones for decades, 

and may cause health effects long after exposure as it is slowly released in the body.

Symptoms of chronic lead poisoning include headache, joint and muscle aches, weakness, fatigue, 

irritability, depression, constipation, anorexia, and abdominal discomfort [Moline and Landrigan 2005]. 

Overexposure to lead may also result in kidney damage, anemia, high blood pressure, infertility and 

reduced sex drive in both sexes, and impotence. In most cases, an individual’s BLL is a good indication of 

recent exposure to lead, with a half-life (the time interval it takes for the quantity in the body to be reduced 

by half its initial value) of 1–2 months [Lauwerys and Hoet 2001; Moline and Landrigan 2005; NCEH 

2005]. Elevated ZPP levels have also been used as an indicator of chronic lead intoxication; however, other 

Appendix B: Occupational Exposure Limits and Health Effects

 (continued)
Health Hazard Evaluation Report 2008-0275-3146 Page 21

factors, such as iron deficiency, can cause an elevated ZPP level, so the BLL is a more specific test for 

evaluating occupational lead exposure.

Under the OSHA general industry lead standard (29 CFR 1910.1025), the PEL for airborne exposure to 

lead is 50 μg/m3 for an 8-hour TWA. The standard requires lowering the PEL for shifts exceeding 8 hours, 

medical monitoring for employees exposed to airborne lead at or above the AL of 30 μg/m3 (8-hour TWA), 

medical removal of employees whose average BLL is 50 μg/dL or greater, and economic protection for 

medically removed workers. Medically removed workers cannot return to jobs involving lead exposure until 

their BLL is below 40 μg/dL. NIOSH has an REL for lead of 50 μg/m3 averaged over an 8-hour work shift 

[NIOSH 2010]. ACGIH has a TLV for lead of 50 μg/m3 (8-hour TWA), with worker BLLs to be controlled 

to or below 30 μg/dL, and designation of lead as an animal carcinogen [ACGIH 2011].

The NIOSH REL is consistent with the OSHA PEL, which is intended to maintain worker BLLs below 40 

μg/dL. This is also intended to prevent overt symptoms of lead poisoning, but is not sufficient to protect 

workers from more subtle adverse health effects like hypertension, renal dysfunction, and reproductive and 

cognitive effects [Schwartz and Stewart 2007; Schwartz and Hu 2007; Brown-Williams et al. 2009]. 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 μg/dL [Sussell 1998]. Recommendations from 

the March 2007 edition of Environmental Health Perspectives’ Mini-Monograph on adult lead exposure 

and from the Association of Occupational and Environmental Clinics include advising workers and 

shooters that BLLs should be kept below 10 μg/dL [CSTE 2009].

In homes with a family member occupationally exposed to lead, care must be taken to prevent “take 

home” of lead, that is, lead carried into the home on clothing, skin, hair, and in vehicles. High BLLs in 

resident children and elevated concentrations of lead in the house dust have been found in the homes of 

workers employed in industries associated with high lead exposure [Grandjean and Bach 1986]. Particular 

effort should be made to ensure that children of persons who work in areas of high lead exposure receive a 

BLL test. The current CDC screening guidelines for children use 10 μg/dL as a “level of concern” in order 

to intervene and prevent long-term cognitive deficits [CDC 2005].

Lead-contaminated surface dust represents a potential source of lead exposure, particularly for young 

children. This may occur either by direct hand-to-mouth contact, or indirectly from hand-to-mouth 

contact with contaminated clothing, cigarettes, or food. Previous studies have found a significant 

correlation between resident children’s BLLs and house dust lead levels [Farfel and Chisholm 1990]. In 

the workplace, generally there is little or no correlation between surface lead levels and employee exposures 

because ingestion exposures are highly dependent on personal hygiene practices and available facilities 

for maintaining personal hygiene. No current federal standard provides a permissible limit for lead 

contamination of surfaces in occupational settings.

Appendix B: Occupational Exposure Limits and Health Effects

 (continued)
Page 22 Health Hazard Evaluation Report 2008-0275-3146

References

ACGIH [2011]. 2011 TLVs® and BEIs®: threshold limit values for chemical substances and physical 

agents and biological exposure indices. Cincinnati, OH: American Conference of Governmental 

Industrial Hygienists.

AIHA [2011]. AIHA 2011 Emergency response planning guidelines (ERPG) & workplace environmental 

exposure levels (WEEL) handbook. Fairfax, VA: American Industrial Hygiene Association.

Brown-Williams H, Lichterman J, Kosnett M [2009]. Indecent exposure: lead puts workers and families at 

risk. Health Research in Action, University of California, Berkeley. Perspectives 4(1)1–9.

CDC [2005]. Preventing lead poisoning in young children. Atlanta: Centers for Disease Control and 

Prevention. [http://www.cdc.gov/nceh/lead/publications/prevleadpoisoning.pdf]. Date accessed: October 

2011.

CFR. Code of Federal Regulations. Washington, DC: U.S. Government Printing Office, Federal Register.

CSTE [2009]. Public health reporting and national notification for elevated blood lead levels. CSTE 

position statement 09-OH-02. Atlanta: Council of State and Territorial Epidemiologists [http://www.cste.

org/ps2009/09-OH-02.pdf]. Date accessed: October 2011.

Farfel MR, Chisholm JJ [1990]. Health and environmental outcomes of traditional and modified practices 

for abatement of residential lead–based paint. Am J Pub Health 80(10):1240–1245.

Grandjean P, Bach E [1986]. Indirect exposures: the significance of bystanders at work and at home. Am 

Ind Hyg Assoc J 47(12):819–824.

Lauwerys RR, Hoet P [2001]. Biological monitoring of exposure to inorganic and organometallic 

substances. In: Industrial chemical exposure: guidelines for biological monitoring. 3rd ed. Boca Raton, FL: 

CRC Press, LLC, pp. 21–180.

Moline JM, Landrigan PJ [2005]. Lead. In: Textbook of clinical occupational and environmental medicine. 

Rosenstock L, Cullen MR, Brodkin CA, Redlich CA, eds. 2nd ed. Philadelphia, PA: Elsevier Saunders, 

pp. 967–979.

NCEH [2005]. Third national report on human exposure to environmental chemicals. Atlanta, GA: U.S. 

Department of Health and Human Services, Centers for Disease Control and Prevention. National Center 

for Environmental Health Publication No. 05–0570.

Appendix B: Occupational Exposure Limits and Health Effects

 (continued)
Health Hazard Evaluation Report 2008-0275-3146 Page 23

NIOSH [2009]. NIOSH alert: preventing occupational exposures to lead and noise at indoor firing 

ranges. 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. 

2009-136.

NIOSH [2010]. NIOSH pocket guide to chemical hazards. 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. 2010-168c. [http://www.cdc.gov/niosh/npg/]. Date 

accessed: October 2011.

Schwartz BS, Hu H [2007]. Adult lead exposure: time for change. Environ Health Perspect 115(3):451–454.

Schwartz BS, Stewart WF [2007]. Lead and cognitive function in adults: a question and answers approach 

to a review of the evidence for cause, treatment, and prevention. Int Rev Psychiatry 19(6):671–692.

Sussell A [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.

Appendix B: Occupational Exposure Limits and Health Effects

 (continued)
Page 24 Health Hazard Evaluation Report 2008-0275-3146

Appendix C: Tables

 

Table C1. Bay 1 ventilation flow rates (fpm) measured on January 13, 2009

Firing Lane # Firing Line First Exhaust Air Vent Bullet Trap

(~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*)

1 100 40 15 20 10 15

2 10 2 10 30 5 5

3 50 20 10 30 15 20

4 25 40 20 20 30 30

5 40 30 40 20 30 30

6 70 25 30 30 30 40

7 100 10 20 60 10 40

8 20 15 50 30 1 30

Average 52 23 24 30 16 26

Total average 37 27 21

Total downrange average 24

* Height at which the rate of airflow was measured.

Table C2. Bay 2 ventilation flow rates (fpm) measured on January 13, 2009

Firing Lane # Firing Line First Exhaust Air Vent Bullet Trap

(~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*)

9 60 20 50 40 3 20

10 80 40 30 20 3 30

11 60 20 40 40 10 30

12 80 50 40 60 10 30

13 70 35 40 40 25 30

14 50 10 40 30 10 10

15 70 0 20 30 30 30

16 30 40 30 25 2 20

Average 63 27 36 35 12 25

Total average 45 36 18

Total downrange average 27

* Height at which the rate of airflow was measured.
Health Hazard Evaluation Report 2008-0275-3146 Page 25

Appendix C: Tables

 (continued)

Table C3. Bay 3 ventilation flow rates (fpm) measured on January 13, 2009

Firing Lane # Firing Line First Exhaust Air Vent Bullet Trap

(~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*)

17 10 50 40 30 30 20

18 80 30 50 50 30 40

19 60 30 60 30 30 30

20 30 40 50 40 20 10

21 25 25 40 10 10 5

22 60 40 40 20 5 5

23 40 30 30 20 10 10

24 30 30 30 30 60 30

Average 42 34 43 29 24 19

Total average 38 36 22

Total downrange average 29

* Height at which the rate of airflow was measured.

Table C4. Bay 1 ventilation flow rates (fpm) measured on December 10, 2009

Firing Lane # Firing Line First Exhaust Air Vent Bullet Trap

(~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*)

1 32 52 33 9 20 12

2 39 29 16 10 11 8

3 56 102 19 8 41 11

4 46 96 21 13 6 10

5 53 55 10 10 13 20

6 27 64 19 20 3 21

7 8 53 4 13 17 7

8 8 47 6 8 13 8

Average 34 63 16 11 16 12

Total average 48 14 14

Total downrange average 14

* Height at which the rate of airflow was measured.
Page 26 Health Hazard Evaluation Report 2008-0275-3146

Appendix C: Tables

 (continued)

Table C5. Bay 2 ventilation flow rates (fpm) measured on December 10, 2009

Firing Lane # Firing Line First Exhaust Air Vent Bullet Trap

(~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*)

9 16 26 52 6 34 13

10 41 28 35 4 14 18

11 18 17 61 16 57 31

12 41 23 23 14 45 18

13 43 34 12 37 25 11

14 51 46 10 14 26 10

15 72 25 27 24 32 17

16 85 13 23 25 6 9

Average 46 26 30 18 30 16

Total average 36 24 23

Total downrange average 24

* Height at which the rate of airflow was measured.

Table C6. Bay 3 ventilation flow rates (fpm) measured on December 10, 2009

Firing Lane # Firing Line First Exhaust Air Vent Bullet Trap

(~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*) (~3 feet*) (~5 feet*)

17 29 21 59 46 29 13

18 64 14 35 17 41 9

19 63 26 41 8 15 12

20 50 48 40 7 34 12

21 52 51 64 26 42 39

22 49 55 69 23 24 29

23 39 28 51 39 14 14

24 74 45 35 48 33 12

Average 52 36 49 27 29 18

Total average 44 38 24

Total downrange average 31

* Height at which the rate of airflow was measured.
Health Hazard Evaluation Report 2008-0275-3146 Page 27

Appendix C: Tables

 (continued)

Table C7. Concentrations of lead on PBZ air samples of instructors

Date Instructor ID Sample Time 

(minutes)

Sample 

Concentration 

(μg/m3)

8-hour TWA 

Concentration 

(μg/m3)

1 369 7.2 5.5

2 373 5.5 4.3

3 367 9.7 7.4

12/08/2009 4 357 11 8.2

5 369 2.0 1.5

6 359 (1.2)* 0.90

7 86 ND† —

1 109 3.7 0.84

3 414 (1.8)* 1.6

4 254 6.1 3.2

12/09/2009 5 416 96 83‡

6 243 ND† —

7 292 7.9 4.8

8 241 ND† —

9 218 (1.2)* 0.55

*Concentrations between the MDC (0.61 μg/m3) and MQC (1.9 μg/m3) are listed in the table in parentheses to 

acknowledge that there is more uncertainty surrounding concentrations below the MQC.

†ND = not detected; the MDC was 0.61 μg/m3 for a 488-liter sample.

‡Exceeds the OELs of 50 μg/m3 for an 8-hour TWA; assumes no exposure for unsampled time during the work shift.

Table C8. Concentrations of lead on PBZ air samples of shooters

Date Shooter Location Sample Time 

(minutes)

Sample 

Concentration 

(μg/m3)

8-hour TWA 

Concentration 

(μg/m3)

Lane 5 120 42 11

Lane 8 145 340* 99*

Lane 9 111 120 28

12/08/2009 Lane 13 108 56 13

Lane 16 111 140 32†

Lane 17 106 65 14

Lane 20 109 55 12

Lane 24 106 130 29

Lane 9 121 58 15

12/09/2009 Lane 11 116 65 16

Lane 14 102 49 10

*Exceeds the OELs of 50 μg/m3 for an 8-hour TWA; assumes no exposure for unsampled time.

†Above the OSHA AL (30 μg/m3); medical monitoring is required for employees exposed to airborne lead at or 

above the AL.
Page 28 Health Hazard Evaluation Report 2008-0275-3146

Appendix C: Tables

 (continued)

Table C9. Concentrations of lead in general area air samples 

Date Location Sample Time (minutes) Sample Concentration 

(μg/m3)

Staff Office 347 ND*

Classroom 337 ND*

12/08/2009 Lunchroom 349 ND*

Firearm cleaning area 343 ND*

Firing range 347 (0.65)†

Firearm cleaning area 413 (0.75)†

12/09/2009 Firing range – cleaning 138 ND*

Firing range 364 3.6

12/10/2009 Firing range – cleaning 115 ND*

*ND = not detected; the MDC was 0.61 μg/m3 for a 488-liter sample.

†Concentrations between the MDC (0.61 μg/m3) and MQC (1.9 μg/m3) are listed in the table in parentheses to 

acknowledge that there is more uncertainty surrounding concentrations below the MQC.

Table C10. Concentrations of lead in floor vacuum samples collected on December 9, 2009

Location Sample Concentration (μg/cm2)

Staff office 0.15

Front office 0.061

Safety supervisor’s office 0.046

Front door rug 0.025

Lunchroom by front door 0.11

Lunchroom by computer workstations 0.071

Firearm cleaning area rug 0.24

Armory door rug 0.31
Health Hazard Evaluation Report 2008-0275-3146 Page 29

Appendix C: Tables

 (continued)

Table C11. Concentrations of lead in surface wipe samples collected on December 8, 2009

Location Sample Concentration (μg/cm2)

Staff office, first workstation behind computer 0.031

Front office, behind computer 0.11

Safety supervisors office, behind TV 0.12

Floor by facility front door 0.058

Floor by firing range door, outside 0.36

Floor, 10 feet behind lane 5 0.54

Floor, 10 feet behind lane 27/28 0.13

Classroom, table 0.019

Classroom, top of microwave 0.032

Lunchroom, middle of lunch table 0.026

Lunchroom, countertop near microwave (0.0045)*

Lunchroom, top of modular cabinet 0.18

Lunchroom, modular desk by computers ND†

Firearm cleaning area, left side front 0.085

Firearm cleaning area, right side back 0.17

Firearm cleaning area, top of filing cabinet 0.77

Firing Range, ammunition table 1 0.25

Firing Range, safety officer station 0.051

Firing Range, ammunition table 2 0.49

Armory shelving unit 2.0

*Concentrations between the MDC (0.004 μg/ cm2) and MQC (0.014 μg/ cm2) are listed in the table in 

parentheses to acknowledge that there is more uncertainty surrounding concentrations below the MQC.

†ND = not detected; below the MDC (0.004 μg/cm2).
Page 30 Health Hazard Evaluation Report 2008-0275-3146

Appendix C: Tables

 (continued)

Table C12. Medical monitoring results, including BLL and ZPP of instructors (data obtained from an FOH 

contractor)

Instructor ID Date

BLL

μg/dL

ZPP

μg/dL Audiograms

03/2011 3 47 25 dB difference 

between left and 

right ear at 6000 Hz

1 06/2010 <3 48

07/2009 3 28

03/2011 6 39

2 06/2010 5 46

06/2008 5 48

03/2011 <3 39

40 dB difference 

between left and 

right ear at 4000 Hz

3 06/2010 5 56

07/2009 6 46

06/2008 5 49

4 03/2011 3 36

06/2010 <3 47

5 03/2011 <3 38

06/2010 <3 45 15 dB

decrement in

right ear at 4000 Hz

6 07/2009 <3 37

06/2008 <3 48

7 06/2010 <3 44

03/2011 <3 41

9 06/2010 <3 51

07/2009 <3 36

06/2010 <3 51 50 dB

decrement in

left ear and 50 dB 

difference between 

left and right ear at 

6000 Hz

10 06/2007 4 ---

11 06/2010 --- ---

20 dB difference 

between left and 

right ear at 6000 Hz
Health Hazard Evaluation Report 2008-0275-3146 Page 31

Acknowledgments and

Availability of Report

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 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 any company or product does not constitute 

endorsement by NIOSH. In addition, citations to websites 

external to NIOSH do not constitute NIOSH endorsement of 

the sponsoring organizations or their programs or products. 

Furthermore, NIOSH is not responsible for the content of these 

websites. All Web addresses referenced in this document were 

accessible as of the publication date.

This report was prepared by Jessica G. Ramsey and R. Todd 

Niemeier of HETAB, Division of Surveillance, Hazard Evaluations 

and Field Studies. Industrial hygiene equipment and logistical 

support was provided by Donald Booher and Karl Feldmann. 

Health communication assistance was provided by Stefanie Evans. 

Editorial assistance was provided by Ellen Galloway. Desktop 

publishing was performed by Greg Hartle.

Copies of this report have been sent to employee and management 

representatives at the firing range, the state health department, 

and the Occupational Safety and Health Administration 

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

reproduced. The report may be viewed and printed at http://

www.cdc.gov/niosh/hhe/. Copies may be purchased from the 

National Technical Information Service at 5825 Port Royal Road, 

Springfield, Virginia 22161.
NIOSH [2011]. Health hazard evaluation report: evaluation of lead 

exposure at an indoor firing range – California. By Ramsey JG and 

Niemeier RT. Cincinnati, OH: U.S. Department of Health and Human 

Services, Centers for Disease Control and Prevention, National Institute 

for Occupational Safety and Health, NIOSH HETA No. 2008-0275-3146. 

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