HETA 92-0034-2356 NIOSH INVESTIGATORS:

OCTOBER 1993 Calvin K. Cook

SAINT BERNARD POLICE Randy L. Tubbs, Ph.D.

DEPARTMENT Matthew K. Klein, P.E.

SAINT BERNARD, OHIO

I. SUMMARY

On October 23, 1991, the National Institute for Occupational Safety and Health (NIOSH)

received a request to conduct a health hazard evaluation (HHE) at the Saint Bernard Police

Department located in Saint Bernard, Ohio. The request was initiated by the management

which was concerned about police officers' exposures to lead fumes generated during monthly

hand gun firing exercises. In response to the request, on January 17, 1992, NIOSH

investigators conducted environmental monitoring to assess potential occupational exposures

to airborne lead and hazardous noise levels generated at the facility during the hand gun firing

exercises.

For three police officers present during the firing exercises, personal breathing-zone (PBZ)

measurements ranged from 36 to 48 micrograms of lead per cubic meter (:g/M3

), based on the

actual sampling time (an average of 72 minutes). PBZ measurements for the three officers,

calculated as an 8-hour time-weighted average (TWA), ranged from 5 to 7 :g/M3

. The 8-hour

TWA calculation assumes that police officers received no additional exposure to lead before

or after leaving the firing range. All PBZ sampling results revealed lead concentrations that

were below the Occupational Safety and Health Administration (OSHA) permissible exposure

limit (PEL) of 50 :g/M3

 calculated as an 8-hour TWA and the NIOSH Recommended

Exposure Limit (REL) of less than 100 :g/M3

 as a 10-hour TWA. Thirteen general area (GA)

air samples ranged from none-detected to 845 :g/M3

, based on the actual sampling time (an

average of 72 minutes). The highest airborne lead concentrations were measured at the bullet

trap of the firing range.

Peak sound pressure levels measured within the firing range were as high as 160 decibels (dB),

which exceeded the OSHA peak exposure criteria of 140 dB. Approximately 180 rounds of

Blazer® and/or Hydra Shok® 9 millimeter (mm) 115 grain lead ammunition were fired during

the exercise.

NIOSH environmental results revealed that there were no overexposures to airborne lead

on the day of the evaluation. GA measurements showed that elevated levels of airborne

lead are generated at the bullet trap in the firing range. If police officers spend more time

in the firing range during firing exercises, the likelihood of increased exposure to

airborne lead will increase. Recommendations are provided in section VII of this report

to: (1) establish improved personal hygiene practices, (2) properly clean the firing range,

and (3) maintain hearing protection devices (HPDs).

KEYWORDS: SIC 9221 (Police Protection), lead, firing range, noise, ventilation.

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
Page 2 - Health Hazard Evaluation Report No. 92-0034

II. INTRODUCTION

On October 23, 1991, the National Institute for Occupational Safety and Health

(NIOSH) received a request to conduct a health hazard evaluation (HHE) at the Saint

Bernard Police Department located in Saint Bernard, Ohio. The request was initiated

by management which was concerned of police officers' exposures to lead fumes

generated during monthly firing exercises. On November 27, 1991, NIOSH conducted

an initial meeting with the management and employee representatives of the police

department, which included a discussion of range procedures and a walk-through

inspection of the firing range. On January 17, 1992, NIOSH investigators returned to

the firing range to conduct an environmental evaluation. An interim report dated

August 4, 1992, presented the preliminary results of the environmental evaluation.

III. BACKGROUND

A. Facility and Firing Range Descriptions

The Saint Bernard Police Department employs a staff of approximately 17 police

officers. Each month the firing range is utilized by four or five police officers for a

period of 1 to 2 hours, who fire their service revolvers for practice or for an annual

small arms qualification requirement of the police department. During each

monthly firing exercise, each police officer fires approximately 60 rounds of 9

millimeter (mm) 115 grain lead ammunition (Blazer® and/or Hydra Shok®). On

the day of the NIOSH evaluation, three police officers participated in the

qualification exercise, with one of the officers also serving as the range officer.

In 1978, the firing range was built on the lower level of the Saint Bernard Police

Department Headquarters. The firing range occupies 2500 square feet (ft2) (125 ft

x 20 ft) of the lower level of the building. The range is comprised of four shooting

booths, each booth being 3 feet wide and 71⁄2 ft high. Located at the rear of the

range is a glass-fronted control booth, a firearms cleaning room, and an exercise

room. The control booth has a raised platform that enables the range officer to

view the range while operating the controls. The floor of the control booth area,

including the platform, is carpeted. Located approximately 70 feet down range

from the shooting booths is a "V" shaped bullet trap, constructed of overlapping,

angled metal plates.

Other areas on the lower level of the building include storage rooms, mechanical

rooms, and a locker room. These areas usually are not occupied for extended

periods of time by the occupants of the building.

B. Heating, Ventilating, and Air-Conditioning (HVAC) Description

The firing range is served by a dedicated, variable air volume (VAV) heating,

ventilating, and air-conditioning (HVAC) system. Ventilation is provided by air

handling unit (AHU) #1 which distributes supply air (SA) to the control booth

through two 24 inch x 24 inch, 4-way, louvered ceiling diffusers. The design SA

flow for the control booth is 790 cubic feet per minute (cfm), distributed to the

range via linear diffusers located in the ceiling about one foot from the wall
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separating the control booth and the range. These diffusers run the full width of

the range. The designed SA flow for the range is 9,230 cfm. Air exhausted or

recirculated from the range is first passed through a high efficiency particulate air

(HEPA) filter. An inline exhaust fan is located downstream of the HEPA filter. A

discharge damper, located downstream of the HEPA filter, regulates the amount of

air either recirculated or exhausted directly to the outdoors. Located upstream of

the AHU, is a SA damper that regulates the amount of outside air (OA) provided to

the range area. Both dampers are controlled by a timer switch that is located in the

control booth.

Exhaust air is discharged at three locations. Located approximately 12 feet

downrange from the shooting booths (between the bullet deflectors near the

ceiling) are two 26 inch x 18 inch exhaust grills. These grills are designed to

exhaust air from the range at a volumetric flowrate of 1595 cfm. A third exhaust

diffuser (66 inch x 42 inch), designed to exhaust 7980 cfm from the range, is

located on the left wall above the bullet trap.

The range is heated by electric heating coils located downstream of the mixed air

plenum. The range is cooled by water chilled cooling coils located upstream of the

mixed-air plenum, which is the room that houses the AHU.

The ventilation system has two operational modes: a recirculation mode and an

exhaust mode. When the range is not being utilized, the ventilation system is

operated in the recirculation mode. During firing exercises, the ventilation system

is operated in the exhaust mode. In the recirculation mode, OA air is neither

supplied to nor exhausted from the range (to the outdoors). In the exhaust mode,

100% OA is brought into the range, and 100% of the range air is exhausted directly

to the outdoors.

C. Previous Evaluation

In November 1979 and January 1980, NIOSH conducted a HHE of the Saint

Bernard Police indoor firing range. The evaluation was prompted by concerns that

smoke filled the control booth during firing exercises. During that evaluation,

police officers fired approximately 60 rounds using .38 special, 148 grain

Wadcutter ammunition. 8-hour TWA PBZ measurements showed that police

officers' lead exposures ranged from 170 to 32,500 :g/M3

, with a mean of 9,700

:g/M3. Many of the lead concentrations measured exceeded the Occupational

Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) of

50 :g/M3 as an 8-hour time-weighed average (TWA). It was concluded that a

hazard from exposure to lead existed at the firing range, and that a serious health

hazard could result if the range was used more frequently or for prolonged periods

of time. Recommendations were provided to reduce lead exposures by improving

the ventilation in the range. 

IV. ENVIRONMENTAL EVALUATION AND METHODS

On January 17, 1992, 16 air samples were collected during the qualification period on

mixed cellulose ester (MCE) filters, using battery-powered air sampling pumps

operated at a flowrate of 2 liters per minute. Three personal breathing-zone (PBZ)
Page 4 - Health Hazard Evaluation Report No. 92-0034

samples were collected to assess police officers' exposures to airborne lead. Thirteen

general area (GA) air samples were taken during the firing exercise for the purpose of

assessing lead concentrations within the firing range and in adjacent areas. Air samples

were analyzed according to NIOSH Method 7082, using a Perkin-Elmer Model 5000

flame atomic absorption (AA) spectrometer.1

Area noise measurements were made in the firing range with a Larson-Davis

Laboratories Model 800B Precision Integrating Sound Level Meter (SLM) fitted with a

Model 2530 1/4" microphone. Unweighted measurements of weapon noise were made

with the SLM in the integration mode, using a 3 decibel (dB) integration equation (Leq). 

The SLM was mounted on a tripod located 5 feet behind the shooting line with the

microphone at ear level near the range officer. One additional measurement was made

in the control booth. The SLM was calibrated with an acoustical reference tone both

before and after the measurement period.

A Rosco Fog Machine (Model Number 8560) was used to visualize the air flow

patterns in the range with a non-hazardous artificial smoke generated by boiling a

mixture of three glycols and distilled water. The smoke machine was placed on the

shelf and on the floor beneath the shelf in each shooting booth. This test checked the

backward flow of air from downrange. In addition, the smoke machine was placed

about 4 feet off the floor in the center of the range about 10 feet downrange from the

booths.

V. 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 from eight to ten hours a day, forty hours a

week, for a working lifetime without experiencing adverse health effects. However, it

is important to note that not all workers will be protected from adverse health effects if

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). In addition, some hazardous substance

may act in combination with other workplace exposures, the general environment, or

with medications or personal habits of the worker to produce health effects even if the

occupational exposures are controlled to the level set by the evaluation criteria. Also,

some substances are absorbed by direct contact with the skin and mucous membranes,

thus potentially increasing the overall exposure. Finally, evaluation criteria may

change over the years as new information on the toxic effects of an agent become

available.

The primary sources of environmental evaluation criteria for the workplace are: 1)

NIOSH Criteria Documents and Recommended Exposure Limits (RELs), 2) the

American Conference of Governmental Industrial Hygienists' (ACGIH) Threshold

Limit Values (TLVs), and 3) the US Department of Labor OSHA PELs.2-4 In

evaluating the exposure levels and the recommendations for reducing those levels

found in this report, it should be noted that industry is legally required to meet those

levels specified by an OSHA PEL.
Page 5 - Health Hazard Evaluation Report No. 92-0034

A TWA exposure level refers to the average airborne concentration of a substance

during a normal eight to ten hour workday. Some substances have recommended shortterm exposure limits (STEL) or ceiling values which are intended to supplement the

TWA where there are recognized toxic effects from brief high exposures.

A. Lead

Inhalation (breathing) of dust and fume, and ingestion (swallowing) resulting from

hand-to-mouth contact with lead-contaminated food, cigarettes, clothing, or other

objects are the major routes of worker exposure to lead. Once absorbed, lead

accumulates in the soft tissues and bones, with the highest accumulation initially in

the liver and kidneys.5

 Lead is stored in the bones for decades, and may cause

toxic effects as it is slowly released over time. Overexposure to lead results in

damage to the kidneys, gastrointestinal tract, peripheral and central nervous

systems, and the blood-forming organs (bone marrow).

The frequency and severity of symptoms associated with lead exposure increase

with increasing blood lead levels (BLLs). Signs or symptoms of acute lead

intoxication include weakness, excessive tiredness, irritability, constipation,

anorexia, abdominal discomfort, colic, anemia, high blood pressure, irritability or

anxiety, fine tremors, pigmentation of the gums ("lead line"), and "wrist drop."6-8

Overt symptoms of lead poisoning in adults generally begin at BLLs between 60

and 120 :g/dl. Neurologic, hematologic, and reproductive effects, however, may

be detectable at much lower levels, and the World Health Organization (WHO) has

recommended an upper limit of 40 :g/dl for occupationally exposed adult males.9

The mean serum lead level for U.S. men from 1976-1980 was 16 :g/dl.10,11

However, with the implementation of lead-free gasoline and reduced lead in food,

the 1991 average serum lead level of U.S. men will probably drop below 9 :g/dl.12

An increase in an individual worker's BLL can mean that the worker is being

overexposed to lead. While the BLL is a good indication of recent exposure to,

and current absorption of lead, it is not a reliable indication of the total body

burden of lead.13 Lead can accumulate in the body over time and produce health

effects long after exposure has stopped. Long-term overexposure to lead may

cause infertility in both sexes, fetal damage, chronic kidney disease (nephropathy),

and anemia. 

Under the OSHA standard regulating occupational exposure to inorganic lead in

general industry, the PEL is 50 μg/m3

 as an 8-hour TWA.14 The standard requires

semi-annual monitoring of BLL for employees exposed to airborne lead at or above

the Action Level of 30 μg/m3 (8-hour TWA), specifies medical removal of

employees whose average BLL is 50 μg/dl or greater, and provides economic

protection for medically removed workers. The NIOSH REL for lead is less than

100 μg/m3 as a TWA for up to 10 hours. This REL is an air concentration to be

maintained so that worker blood lead levels remain below 60 μg/100 grams of

whole blood. NIOSH is presently reviewing literature on the health effects of lead

to re-evaluate its REL. The OSHA PEL for general industry is currently

recommended by NIOSH investigators as a more protective criteria. 
Page 6 - Health Hazard Evaluation Report No. 92-0034

Recent studies suggest that there are adverse health effects at BLLs below the

current evaluation criteria for occupational exposure. A number of studies have

found neurological symptoms in workers with BLLs of 40 to 60 μg/dl. Male BLLs

are associated with increases in blood pressure, with no apparent threshold through

less than 10 μg/dl. Studies have suggested decreased fertility in men at BLLs as

low as 40 μg/dl. Prenatal exposure to lead is associated with reduced gestational

age, low birthweight, and early mental development at prenatal maternal BLLs as

low as 10 to 15 μg/dl.15 

In recognition of the health risks associated with exposure to lead, a goal for

reducing occupational exposure was specified in Healthy People 2000, a recent

statement of national consensus and U.S. Public Health Service policy for health

promotion and disease prevention. The goal is to eliminate, by the year 2000, all

workplace exposures that result in BLLs greater than 25 μg/dl.16 

Lead dust may be carried home on clothing, skin, and 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.17 Particular efforts should be made to ensure that children of

workers with lead poisoning, or who work in areas of high lead exposure, are

tested for lead exposure (BLL) by a qualified health-care provider.

B. Noise

Occupational deafness was first documented among metalworkers in the sixteenth

century.18 Since then, it has been shown that workers have experienced excessive

hearing loss in many occupations associated with noise. Noise-induced loss of

hearing is an irreversible, sensorineural condition that progresses with exposure. 

Although hearing ability declines with age (presbycusis) in all populations,

exposure to noise produces hearing loss greater than that resulting from the natural

aging process. This noise-induced loss is caused by damage to nerve cells of the

inner ear (cochlea) and, unlike some conductive hearing disorders, cannot be

treated medically.19

While loss of hearing may result from a single exposure to a very brief impulse

noise or explosion, such traumatic losses are rare. In most cases, noise-induced

hearing loss is insidious. Typically, it begins to develop at 4000 or 6000 Hz (the

hearing range is 20 Hz to 20000 Hz) and spreads to lower and higher frequencies. 

Often, material impairment has occurred before the condition is clearly recognized. 

Such impairment is usually severe enough to permanently affect a person's ability

to hear and understand speech under everyday conditions. Although the primary

frequencies of human speech range from 200 Hz to 2000 Hz, research has shown

that the consonant sounds, which enable people to distinguish words such as "fish"

from "fist," have still higher frequency components.20

The OSHA standard for occupational exposure to noise (29 CFR 1910.95)21

specifies a maximum PEL of 90 dB(A)-slow response for a duration of 8 hours per

day. The regulation, in calculating the PEL, uses a 5 dB time/intensity trading

relationship. This means that in order for a person to be exposed to noise levels of

95 dB(A), the amount of time allowed at this exposure level must be cut in half in

order to be within OSHA's PEL. Conversely, a person exposed to 85 dB(A) is
Page 7 - Health Hazard Evaluation Report No. 92-0034

allowed twice as much time at this level (16 hours) and is within his daily PEL. 

Both NIOSH, in its Criteria for a Recommended Standard,22 and the ACGIH, in

their TLVs,23 propose an exposure limit of 85 dB(A) for 8 hours, 5 dB less than the

OSHA standard. Both of these latter two criteria also use a 5 dB time/intensity

trading relationship in calculating exposure limits.

TWA noise limits as a function of exposure duration are shown as follows:

Duration of Exposure Sound Level (dB[A])

Hours/day ACGIH/NIOSH OSHA

16 80 85

8 85 90

4 90 95

2 95 100

1 100 105

1⁄2 105 110

1⁄4 110 115*

c 115* ---**

 * No exposure to continuous or intermittent noise in excess of 115 dB(A).

 ** Exposure to impulsive or impact noise should not exceed 140 dB(A) peak sound pressure level.

The OSHA regulation has an additional action level (AL) of 85 dB(A) which

stipulates that an employer shall administer a continuing, effective hearing

conservation program when the TWA value exceeds the AL. The program must

include monitoring, employee notification, observation, an audiometric testing

program, hearing protectors, training programs, and recordkeeping requirements. 

All of these stipulations are included in 29 CFR 1910.95, paragraphs (c) through

(o).

The OSHA noise standard also states that when workers are exposed to noise

levels in excess of the OSHA PEL of 90 dB(A), feasible engineering or

administrative controls shall be implemented to reduce the workers' exposure

levels. Also, a continuing, effective hearing conservation program shall be

implemented.

VI. RESULTS

A. Air Sampling for Lead

Results of the PBZ and GA air sampling for lead are presented in Table 1. Based

on the actual sampling time (an average of 72 minutes), PBZ lead concentrations

ranged from 36 to 48 :g/M3 for the three police officers present during the firing

exercise. The calculated 8-hour TWAs for PBZ concentrations of airborne lead

ranged from 5 to 6 :g/M3, well below the OSHA PEL of 50 :g/M3. The 8-hour

TWA calculation assumes that police officers received no additional exposure to

lead before or after leaving the firing range. Lead concentrations determined from
Page 8 - Health Hazard Evaluation Report No. 92-0034

the GA air samples ranged from none-detected to 845 :g/M3

, with the highest lead

concentrations (438 :g/M3 to 845 :g/M3) measured at the bullet trap of the firing

range. The remaining GA air samples revealed lead concentrations at or below 30

:g/M3.

B. Noise Measurements

Because of the explosive nature of gunfire, only the peak sound pressure levels

from the weapons were recorded. Noise measurements were made when either

one, two, or all three officers were firing their weapons. The number of shooters

did not appear to have a large effect on the noise levels recorded on the stationary

SLM. When all three officers were firing, the peak sound pressure level was 160

dB. Two shooters were exposed to 157 dB peak levels and one officer firing on the

range was also measured at 157 dB. The noise in the range control room was
Page 9 - Health Hazard Evaluation Report No. 92-0034

Table 1

PBZ and Area Air Sampling Results\Data for Lead January 17, 1992

St. Bernard Police Department St. Bernard, Ohio

Sampling Period Lead Conc. (μg/M3

)

Job Title/Location Begin End Time (min)1 TWA2 8-hr TWA

Personal Sampling

Range Officer 3:06 4:16 70 36 5

Shooter #1 3:05 4:11 66 44 6

Shooter #2 3:08 4:14 67 48 7

Area Sampling

Booth #1 3:08 4:19 73 13 ---

Booth #2 3:10 4:24 75 20 ---

Booth #3 3:08 4:19 72 20 ---

Booth #4 3:09 4:21 73 21 ---

Bullet trap (R) 3:10 4:21 73 438 ---

Bullet trap (L) 3:09 4:22 71 845 ---

Range Desk 3:08 4:18 71 7 ---

Table behind booths (L) 3:10 4:23 74 30 ---

Table behind booths (R) 3:10 4:23 74 20 ---

Control room table 3:09 4:17 70 ND ---

Cleaning room 3:10 4:23 73 ND ---

Hallway 3:12 4:18 71 ND ---

Outdoors 3:13 4:18 77 ND ---

OSHA PEL 50 μg/M3

NIOSH REL 100 μg/M3

ACGIH TLV 150 μg/M3

1Total number of minutes sampled. 2TWA for sampling time. 3μg/M3

 micrograms per cubic meter.

(R) = right side

(L) = left side

ND = None detected below the minimum detectable concentration of 0.007 μg based on a sampling volume of 150 liters.

measured at 134 dB peak levels; 13-16 dB less than the noise levels measured in

the range.

One type of ear muffs worn by the officers during qualification was determined to

be less than optimal for attenuating the high peak levels of noise that they were

exposed to during shooting. Due to the age of the MSA ear muffs, the cushions on

the edge of the ear cups lost their pliancy. The cushions need to be replaced
Page 10 - Health Hazard Evaluation Report No. 92-0034

periodically to maintain the muffs' maximal attenuation characteristics. The E-A-R

ear muffs (Cabot Corporation) have an orifice in the ear cup which covers the ear. 

At noise levels below a critical sound level (the transition level), sound can enter

the ear cups through orifice openings, allowing conversations and other low level

sounds to be better heard when the ambient noise levels are low. However, above

the transition level, the air turbulence created by the high noise levels restricts the

passage of sound through the opening. The transition sound level for these ear

muffs is 120 dB, making them appropriate for isolated impulses such as gunfire. 

However, cushions on these muffs also must be changed periodically to assure

maximal attenuation from the product.

C. Ventilation

The information presented below discusses the findings of the smoke machine

assessment of airflow patterns at each firing booth and down range of the firing

booths. The firing booths are referred to by number starting from left to right while

facing downrange.

1. Firing Booth 1: Smoke released at both the shelf and at the floor levels

backflowed immediately to the area uprange of the booth.

2. Firing Booth 2: Smoke released at the shelf level did not backflow uprange of

the firing booths. Smoke released at floor backflowed intermittently uprange

of the booth.

3. Firing Booth 3: Smoke released at the shelf level backflowed uprange of the

booth, but the amount of smoke that backflowed through booth 3 appeared to

be less than and more intermittent than that noted in booth 1. Smoke released

at the floor level did not move uprange.

4. Firing Booth 4: Smoke released at shelf level in booth 4 did not backflow

through the booth. Smoke released at floor level backflowed through the

booth.

5. Smoke testing downrange of the booths (near the bullet trap): the test

showed that air from downrange backflowed uprange toward the booths. This

smoke flowed from the ceiling space through the exhaust grille uprange of the

booths, and through cracks in the suspended ceiling and around light fixtures. 

The exhaust grill system appeared to have minimal effect on the smoke.

In all cases, smoke that backflowed uprange of the booths flowed to the control

booth area, flowed up the wall, and mixed with air flowing from the linear

diffusers. The smoke was then blown through the booths with the supply air. 

Smoke released in any booth tended to spread throughout the area uprange of the

booths. Smoke uprange of the booths dissipated slowly--smoke was still visible

after ten minutes after the Rosco machine had been stop.
Page 11 - Health Hazard Evaluation Report No. 92-0034

VII. DISCUSSION

It was estimated by the management that the range officer spends approximately 24 hours

per year in the firing range. Considering the short time spent in the firing range, and low

personal lead exposures, overexposure to lead is not likely to occur under these

circumstances and ventilation conditions. However, if the firing range is used more

frequently or for more prolonged periods of time, airborne lead exposures are likely to

increase.

Four or five police officers generally use the firing range during the qualification period. 

However, only three police officers fired on the day of the NIOSH evaluation. 

Consequently, airborne lead concentrations may be higher on days when more than three

officers participate.

Although PBZ lead concentrations were relatively low, there is a potential for carrying

lead dust away from the firing range on contaminated clothing and shoes. This could lead

to lead dust exposure to other people such as co-workers and family members.

The smoke machine results illustrate that shooters standing in booths 1 and 3 can be

directly exposed to lead-contaminated air originating downrange of the shooting booths. 

Booths 2 and 4 also demonstrated this backflow of air but because air flow was in the

lower part of the booth, shooters in these booths may not inhale lead-contaminated air

unless they shoot from the prone position. Shooters in all of the booths, as well as anyone

uprange of the booths, are potentially exposed to lead-contaminated air that was shown to

backflow from down range.

The backflow of air at the firing booths is caused by the way air is supplied to the range. 

Linear diffusers across the ceiling supply air to the range in a high velocity jet. 

Surrounding air is pulled into the jet of air because of the turbulence between the jet

boundary and surrounding air, thus creating a siphoning effect.

Openings were observed around the sanitary pipes which enter from the floor above the

range through the ceiling. Under certain conditions, lead contaminated air could enter

these openings.

VIII. RECOMMENDATIONS

The following recommendations are offered to further reduce the lead exposures, and to

protect the officers from hazards to their hearing from gunfire noise:

1. Establish and enforce personal hygiene practices designed to prevent the ingestion

of lead dust by police officers, and contaminating areas outside the firing range

with lead.

a. Eating, drinking, or smoking inside the range should be prohibited to eliminate

possible hand to mouth ingestion.

b. After using the range, individuals should shower and change clothes before

eating, drinking, and using tobacco products. Range officers should be
Page 12 - Health Hazard Evaluation Report No. 92-0034

provided with two lockers to allow them to separate street clothes from lead

contaminated work clothes.

2. A schedule should be established to perform routine cleaning and maintenance of

the range. The following provides information about proper cleaning of the range:

a. Lead dust that accumulates in the bullet trap should be removed. The

Environmental Protection Agency (EPA) classifies lead as a hazardous

material, and requires disposal in accordance with environmental regulations.24

b. Because of the presence of unburnt gun powder, cleaning the range floor and

bullet trap should include the use of an explosion-proof HEPA vacuum, or one

which utilizes a wet dust collector. Because sweeping with brooms will

disperse lead dust into the air, they should be avoided when cleaning the range. 

In addition, assessable surfaces (e.g., floors, table tops, and bullet traps) in the

range should be cleaned routinely with a high phosphorous detergent, such as

trisodium phosphate (TSP) or Spic and Span®. All cleaning in the range

should be performed with the ventilation system running in the exhaust mode.

c. Spent cartridges should not be picked up by hand to avoid dermal contact with

lead from the bullets and from the floor. Instead, they should be collected

using a HEPA vacuum.

3. A respiratory protection program should be established for personnel assigned to

cleaning the range, and removing lead dust from the bullet trap. The program

should be established in accordance with OSHA regulation 29 CFR 1910.134.4

4. Sampling results show elevated lead concentrations measured at the bullet trap area

of the range. Following firing exercises, police officers were observed walking

downrange toward the bullet trap. To prevent further lead exposures, only

authorized personnel (range officers or maintenance personnel) should be

permitted to go downrange of the firing line. Personnel who walk downrange

should wear disposable clothing to cover portions of the body that will come in

contact with surfaces covered with lead.

5. Carpet that is located in the control booth area of the range acts as a reservoir for

lead dust and gun powder. The carpet in that area should be removed to reduce a

potential fire hazard posed by unburnt gun powder and to minimize lead exposures. 

The carpet should be replaced with a seamless, rubberized surface. This would

provide sound absorption as well as reducing lead hazards and making clean-up

easier.

6. The use of low-lead ammunition should be considered. Substituting copper

jacketed, nylon jacketed, or zinc slugs has been shown to reduce lead emission

significantly.25 

7. To prevent lead contaminated air from entering areas on the first floor of the

building, the sanitary pipes (as discussed in section VII of this report) leading to the

first floor should be sealed.
Page 13 - Health Hazard Evaluation Report No. 92-0034

8. Because the officers are subject to peak noises levels up to 160 dB during periods

of gunfire, all personnel must wear hearing protection while on the range. This

should include officers firing their weapons, range instructors, and anyone else

who is on the range, in the range control room, or in the rooms which are accessed

from the control room. A warning light should be placed in the hallway outside of

the range to warn people in the hall that weapon firing is taking place and that they

must have hearing protection in place before entering the range area.

9. Hearing protection must be supplied to all personnel who may enter the firing

range area. If ear muffs are the device of choice, then a periodic maintenance

program must be instituted. The maintenance program must check to see that the

headbands of the muffs have not been sprung which will result in not enough

pressure being applied to the side of the person's head to adequately block out

noise from entering the ear through a pathway between the ear cup and the head. 

The cushions should be replaced every six months to assure that they are pliant. 

Ear plugs should be available for those people who are unable to wear ear muffs

because of facial deformities or glasses that break the seal between the head and

ear muff.

 10. Annual audiometric examinations should be instituted to check officers' hearing

because of the potential for exposure to damaging noise. If an officer shows a

reduction in high frequency hearing from one year to the next in spite of the use of

hearing protection, the officer can be refit with another type of hearing protection

device or instructed to use both ear plugs and ear muffs while on the range. The

annual audiometric test will identify potentially serious hearing problems in

officers before they become excessive.
Page 14 - Health Hazard Evaluation Report No. 92-0034

IX. REFERENCES

1. NIOSH [1984]. Manual of Analytical Methods, Third Edition. Cincinnati, OH: U.S.

Department of Health and Human Services, Public Health Service, Centers for

Disease Control, National Institute for Occupational Safety and Health, DHHS

(NIOSH) Publication No. 84-100. 

2. CDC [1988]. NIOSH recommendations for occupational safety and health standards

1988. Atlanta, GA: U.S. Department of Health and Human Services, Public Health

Service, Centers for Disease Control; National Institute for Occupational Safety and

Health. MMWR 37 (supp. S-7).

3. ACGIH [1990]. Threshold limit values and biological exposure indices for 1990-

1991. Cincinnati, OH: American Conference of Governmental Industrial Hygienists.

4. Code of Federal Regulations [1989]. 29 CFR 1910.1000. Washington, DC: U.S.

Government Printing Office, Federal Register.

5. NIOSH [1981]. Occupational health guidelines for chemical hazards. Cincinnati,

OH: U.S. Department of Health and Human Services, Public Health Service, Centers

for Disease Control, National Institute for Occupational Safety and Health, DHHS

(NIOSH) Publication No. 81-123, and supplements 88-118, 89-104.

6. Hernberg S, et al. [1988]. Lead and its compounds. In: Occupational medicine. 2nd

ed. Chicago, IL: Year Book Medical Publishers. 

7. 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.

8. Proctor NH, Hughes JP, Fischman ML [1988]. Lead. In: Chemical hazards of the

workplace. 2nd ed. Philadelphia, PA: J.B. Lippincott Company, Philadelphia, pp

294-298.

9. World Health Organization [1980]. Recommended health-based limits in

occupational exposure to heavy metals. Geneva: Technical Report Series 647.

10. Muhaffey K, Annest J, Roberts J, Murphy R [1982]. National estimates of blood lead

levels. United States, 1976-1980. New Engl J Med 307:373-9.

11. Annest J, Dirkle J, Makuc C, Nesse J, Bayse D, Kovar M [1983]. Chronological

trends in blood lead levels between 1976 and 1980. New Engl J Med 308:1373-7.

12. CDC [1991]. Strategic plan for the elimination of childhood lead poisoning. U.S.

Department of Health and Human Services, Public Health Service, Centers for

Disease Control.

13. 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.

14. Code of Federal Regulations [1989]. OSHA lead standard. 29 CFR, Part 1910.1025. 

Washington, DC: U.S. Government Printing Office, Federal Register. 
Page 15 - Health Hazard Evaluation Report No. 92-0034

15. ATSDR [1990]. Toxicological profile for lead. Atlanta, GA: U.S. Department of

Health and Human Services, Public Health Service, Agency for Toxic Substances and

Disease Registry. DHHS (ATSDR) Publication No. TP-88/17.

16. DHHS [1990]. Healthy people 2000: National health promotion and disease

objectives. Washington, DC: U.S. Department of Health and Human Services, Public

Health Service, DHHS Publication No. (PHS) 91-50212.

17. Grandjean, P and Bach, E [1986]. Indirect exposures: The significance of bystanders

at work and at home. Am Ind Hyg Assoc J 47(12):819-824.

18. Alberti [1591 (1970)], cited by Bunch, C.C. Traumatic deafness. In E.P. Fowler, Jr.

(Editor), Medicine of the ear, chapter X. Reprinted Translations of the Beltone

Institute for Hearing Research, No. 23.

19. Ward WD [1986]. Anatomy & physiology of the ear: normal and damaged hearing. 

Chapter 5. In: Berger EH, Ward WD, Morrill JC, Royster LH, eds. Noise & hearing

conservation manual. 4th ed. Akron, OH: American Industrial Hygiene Association,

pp. 177-195.

20. Ward WD, Fleer RE, Glorig A [1961]. Characteristics of hearing loss produced by

gunfire and by steady noise. Journal of Auditory Research, 1:325-356.

21. Code of Federal Regulations [1989]. OSHA. 29 CFR 1910.95. Washington, DC: 

U.S. Government Printing Office, Federal Register.

22. NIOSH [1972]. Criteria for a recommended standard: occupational exposure to

noise. Cincinnati, OH: U.S. Department of Health, Education, and Welfare, Health

Services and Mental Health Administration, National Institute for Occupational Safety

and Health, DHEW (NIOSH) Publication No. 73-11001.

23. ACGIH [1990]. 1990-1991 threshold limit values for chemical substances and

physical agents and biological exposure indices. Cincinnati, Ohio: American

Conference of Governmental Industrial Hygienists.

24. Code of Federal Regulations [1992]. EPA. 40 CFR 261. Washington, DC: U.S.

Government Printing Office, Federal Register.

25. NIOSH [1978]. Hazard evaluation and technical assistance report: Kansas City

Federal Reserve Bank, Cincinnati, OH: U.S. Department of Health, Education, and

Welfare, Public Health Service, Center for Disease Control, National Institute for

Occupational Safety and Health, NIOSH Report No. HETA 81-019-846.
Page 16 - Health Hazard Evaluation Report No. 92-0034

X. AUTHORSHIP AND ACKNOWLEDGEMENTS

Report Prepared by: Calvin K. Cook

Randy L. Tubbs

Matthew K. Klein

Field Assistance: Alan S. Echt

Originating Office: Industrial Hygiene Section

Hazard Evaluations and Technical

 Assistance Branch

Division of Surveillance, Hazard 

 Evaluations, and Field Studies

Report Typed By: Donna Pfirman

Office Automation Assistant

Industrial Hygiene Section

XI. DISTRIBUTION AND AVAILABILITY OF REPORT

Copies of this report may be freely reproduced and are not copyrighted. Single copies

of this report will be available for a period of 90 days from the date of this report from

the NIOSH Publications Office, 4676 Columbia Parkway, Cincinnati, Ohio 45226. To

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

request. After this time, copies may be purchased from the National Technical

Information Service (NTIS), 5285 Port Royal Road, Springfield, Virginia 22161. 

Information regarding the NTIS stock number may be obtained from the NIOSH

Publications Office at the Cincinnati address.

Copies of this report have been sent to:

1. St. Bernard Police Department

2. Department of Labor - OSHA, Region V

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.