Air Contaminant, Noise, 

and Dermal Hazards 

during Aluminum 

Beverage Can 

Manufacturing – Texas

Manuel Rodriguez, MS, CIH, CSP

Christine West, RN, MSN/MPH

Scott E. Brueck, MS, CIH

Health Hazard Evaluation Report

HETA 2008-0099-3152

February 2012 

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 2008-0099-3152 Page i

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

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

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

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

Assessment.....................................................................................................2

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

Discussion.................................................................................................... 16

Conclusions................................................................................................. 25

Recommendations.................................................................................... 25

References.................................................................................................... 29

Contents

Acknowledgments Acknowledgments and Availability of Report................................ 51

Appendix A Methods........................................................................................................ 32

Appendix B Tables and Figures..................................................................................... 35

Appendix C Occupational Exposure Limits and Health Effects......................... 44
Page ii Health Hazard Evaluation Report 2008-0099-3152

Abbreviations

ACGIH® American Conference of Governmental Industrial Hygienists

AL Action level

CFR Code of Federal Regulations

CFU/mL Colony forming units per milliliter

dB Decibels

dBA Decibels, A-scale

°F Degrees Fahrenheit

EU/m3 Endotoxin unit per cubic meter

EU/mL Endotoxin unit per milliliter

GA General area

HHE Health hazard evaluation

HTL Hearing threshold level

Hz Hertz

kHz Kilohertz

Lpm Liters per minute

MDC Minimum detectable concentration

mg/m3 Milligrams per cubic meter

MQC Minimum quantifiable concentration

mL Milliliter

MWF Metalworking fluid

NAICS North American Industry Classification System

ND Not detected

NIHL Noise-induced hearing loss

NIOSH National Institute for Occupational Safety and Health

OEL Occupational exposure limit

OSHA Occupational Safety and Health Administration

PBZ Personal breathing zone

PEL Permissible exposure limit

PPE Personal protective equipment

ppm Parts per million

REL Recommended exposure limit

SLM Sound level meter

TLV® Threshold limit value

STEL Short-term exposure limit

STS Standard threshold shift

TWA Time-weighted average

WEELTM Workplace environmental exposure level
Health Hazard Evaluation Report 2008-0099-3152 Page iii

The National Institute for 

Occupational Safety and 

Health (NIOSH) received 

a confidential employee 

request for a health 

hazard evaluation at an 

aluminum beverage can 

manufacturer. Employees 

were concerned 

about exposures to 

metalworking fluids 

(MWFs), inorganic acids, 

printing inks, and noise. 

Employees reported 

having skin rashes, 

headaches, fatigue, 

and upper respiratory 

symptoms.

Highlights of the

NIOSH Health

Hazard Evaluation

What NIOSH Did

● We evaluated the workplace in December 2008 and June 2009.

● We looked at job tasks, work processes, and the equipment 

used. We also looked at employees’ use of personal protective 

equipment.

● We measured employees’ exposures to noise and the 

frequencies of noise that employees were exposed to. We also 

analyzed their hearing tests.

● We took bulk samples of MWFs. These samples were 

analyzed for bacteria, fungi, and endotoxin.

● We took air samples for MWFs, inorganic acids, 

dibutylaminoethanol, formaldehyde, and endotoxin.

● We talked with employees about their work. We asked them 

if they had any health concerns that they thought might be 

related to their work.

● We asked employees to fill out a survey about health 

symptoms. We kept their answers to this survey confidential.

What NIOSH Found

● Employees were overexposed to noise.

● Some employees may have hearing loss from noise exposure 

at work.

● Some employees did not correctly insert their foam earplugs.

● Employees in the lacquer spray, necker, and printer areas 

need to wear ear plugs and ear muffs. Dual hearing 

protection will help protect employees from high noise levels 

in these areas.

● Employees were not overexposed to MWFs, inorganic acids, 

dibutylaminoethanol, or endotoxin.

● Printer operators were exposed to formaldehyde. They must 

be told about this exposure and trained about the hazards.

● A few employees exposed to MWF reported health 

symptoms. The most common symptom was eye irritation.

● No convincing evidence of a relationship between MWF 

exposure and respiratory symptoms was found. We found 

no convincing evidence of a relationship between MWF 

exposure and dermatitis either.

● Bulk samples of MWF had low levels of bacteria and 

endotoxin. No fungi were found in the samples.

What Managers Can Do

● Use engineering controls to reduce noise.

● Require employees to get baseline audiometric tests when 

they are hired. Repeat the audiometric tests every year.
Page iv Health Hazard Evaluation Report 2008-0099-3152

Highlights of the

NIOSH Health

Hazard Evaluation

 (continued)

● Make sure employees wear hearing protection properly.

● Require employees to wear ear plugs and ear muffs in the 

lacquer spray, necker, and printer areas.

● Inform printer operators about the low levels of 

formaldehyde in their work area. Educate them on the health 

hazards of formaldehyde.

● Encourage employees to use a skin moisturizer after they 

wash their hands. They should also use moisturizer before 

and after work to prevent skin problems from MWF and 

other chemicals.

● Use a can cleaner that is safer than hydrofluoric acid.

● Place a biocide dispenser at the MWF sump.

● Check exhaust ventilation systems regularly. Make repairs as 

soon as possible when problems are found.

● Install emergency eyewashes and showers where corrosive 

chemicals are stored or dispensed.

● Check existing emergency eyewash and showers weekly to 

make sure they work.

● Repair leaks as soon as they are identified. This will keep 

liquids from dripping or spilling onto walking surfaces.

● Encourage employees to report work-related health concerns, 

such as skin or breathing problems, to their supervisors.

● Train employees about health hazards from chemicals in the 

workplace.

What Employees Can Do

● Wear hearing protection properly to prevent hearing loss.

● Wear ear plugs and ear muffs when working in the lacquer 

spray, necker, and printer areas.

● Wear gloves to protect your skin from MWFs, biocides, 

inorganic acids, printing inks, and other chemicals.

● Use a skin moisturizer after you wash your hands. Also use 

moisturizer before and after work to prevent skin problems 

from MWF and other chemicals.

● Wear all personal protective equipment that your safety 

manager recommends.

● Report health symptoms that you think are work related to 

your supervisor and follow up with a healthcare provider who 

is familiar with occupational exposures.

● Report all health and safety concerns to your supervisor and 

the health and safety committee.

● Attend all training about safety and health.
Health Hazard Evaluation Report 2008-0099-3152 Page v

NIOSH investigators 

measured employee 

exposures to noise, 

MWFs, acids, 

dibutylaminoethanol, 

formaldehyde, and 

endotoxin at an 

aluminum beverage can 

manufacturer. Employees 

were overexposed to 

noise, and some may have 

noise-induced hearing 

loss. Employees were not 

overexposed to airborne 

chemicals, and those 

surveyed about exposure 

to MWFs reported minimal 

symptoms. Employees 

should avoid skin contact 

with chemicals, use PPE, 

and follow up with a 

doctor if symptoms occur. 

Summary

In January 2008, NIOSH received a confidential employee request 

for an HHE at an aluminum beverage can manufacturer. The 

requestors were concerned about workplace exposures to MWFs, 

inorganic acids, printing inks, and noise. Health problems believed 

to be work related included skin rash, upper respiratory symptoms, 

headaches, and fatigue.

During the initial site visit, investigators observed work processes, 

collected screening air samples for volatile organic compounds, 

and measured noise levels. We talked with employees about their 

work activities and their health. We also reviewed OSHA 300 Logs 

of Work-Related Illnesses and Injuries, material safety data sheets, 

and written health and safety procedures. During our second 

site visit we collected air samples for MWFs, inorganic acids, 

dibutylaminoethanol, formaldehyde, and endotoxin. We analyzed 

bulk samples of MWFs for bacteria, fungi, and endotoxin. We 

measured employees’ noise exposures and took noise frequency 

measurements. We asked employees to complete a confidential 

symptom survey to look at possible associations between MWF 

exposure and dermatitis, respiratory symptoms, and PPE use.

During the second site visit, 128 out of 148 (86%) available plant 

employees completed the symptom survey. The survey data show 

that few employees who were exposed to MWF reported respiratory 

symptoms. We found no convincing evidence of a relationship 

between MWF exposure and work-related respiratory symptoms 

or dermatitis. Of the employees who completed the survey, 16% 

reported dermatitis since starting at the plant. Of 119 employees 

who completed the survey, four reported work-related dermatitis 

during the previous month.

Employees were not overexposed to MWFs, inorganic acids, 

dibutylaminoethanol, or endotoxin during this evaluation. 

Employees’ exposures to formaldehyde were below the OSHA 

PEL-TWA of 0.75 ppm. Two printer operators were exposed to 

formaldehyde above 0.1 ppm, the OSHA level requiring employee 

notification and training. Bacteria and endotoxin levels in the 

bulk MWF samples were very low, and no fungi were detected in 

the samples. This finding indicated that the MWF system was well 

maintained.

All 26 of the monitored employees’ TWA noise exposures 

exceeded the NIOSH REL of 85 dBA for an 8-hour work shift 

and 83.4 dBA for a 12-hour work shift. Printer operators and back 
Page vi Health Hazard Evaluation Report 2008-0099-3152

Keywords: NAICS 331316 (Aluminum Extruded Product 

Manufacturing), beverage can manufacturing, aluminum cans, 

metalworking fluids, MWFs, formaldehyde, noise, octave band 

analysis, hearing loss, audiogram, acids, dermatitis, rash.

Summary

 (continued) end operators who worked in the necker and lacquer spray areas 

had TWA noise exposures greater than 100 dBA. Because OSHA 

uses different noise measurement criteria than NIOSH, TWA 

noise exposures for material handlers, millwrights, palletizers, and 

front end maintenance and repair personnel did not exceed the 

PEL. However, employees’ noise exposures in all of the job titles 

monitored exceeded the OSHA AL of 85 dBA for an 8-hour work 

shift and 82.1 dBA for a 12-hour work shift.

We recommended the company use engineering controls to reduce 

noise levels. We also recommended that employees working in 

the lacquer spray, necker, and printer areas wear dual hearing 

protection (ear plugs and ear muffs) because noise exposures 

exceeded 100 dBA. Additionally, we recommended that employees 

exposed to airborne MWF concentrations exceeding half of the 

REL (0.20 mg/m3

) receive annual medical monitoring. Other 

recommendations included wearing PPE, inspecting the ventilation 

systems, reducing slippery walking surfaces, and reporting all workrelated health symptoms.
Health Hazard Evaluation Report 2008-0099-3152 Page 1

Introduction

NIOSH received a confidential HHE request from employees at an 

aluminum beverage can manufacturer who were concerned about 

exposures to MWFs, inorganic acids, printing inks, and noise. 

The employees’ health concerns included skin rash, headache, 

fatigue, and respiratory symptoms. NIOSH investigators visited the 

company in December 2008 and June 2009. We sent an interim 

report to the plant management and employee requestors with 

preliminary findings on September 1, 2009.

Process Description

The plant operated 24 hours per day with three production 

lines. At the time of the evaluation the plant had 148 production 

employees working 12-hour shifts and 19 non-production 

employees working 8-hour shifts.

The beverage can manufacturing process began by unwinding 

aluminum sheet metal coils. Aluminum sheets were lubricated with 

DTI M3 lubricating oil, stamped by the cupping press to produce 

shallow aluminum cups, then extruded by ironers to form can 

bodies. The tops of the cans were trimmed to a uniform height. 

Synthetic MWF (DTI Atoguard I-102B) was used for lubrication 

and to keep cans and machining tools from overheating during 

extrusion and trimming. This area of the plant was referred to 

as the front end. About 50 employees operated and maintained 

machinery and the MWF system in the front end.

After trimming, cans were cleaned with a heated sulfuric acid 

solution, etched with hydrofluoric acid, and then rinsed. Henkel 

Deoxylite 115 was added to the rinse water to help the cans flow 

smoothly throughout the subsequent printing operation. The 

rinsed cans were dried, and a thin ultraviolet-cured resin was 

applied to the can’s base for abrasion resistance. The cans then 

traveled to one of four printers where an ink label and a varnish 

coating were applied to the exterior. Three rotary printers each had 

a maximum production capacity of 1,300 cans per minute, and 

another printer had a maximum production capacity of 1,800 cans 

per minute. Isopropyl alcohol was used to clean all the printers.

Following printing and coating, the cans passed through one 

of four gas-powered curing ovens. Curing oven emissions were 

captured and exhausted through an incinerator. After curing, a 

protective coating was sprayed inside the cans at the lacquer spray 
Page 2 Health Hazard Evaluation Report 2008-0099-3152

Introduction 

(continued) machines. The cans then went through one of three ovens heated 

to 485°F. Afterwards, a wax film was applied to the top of the cans 

prior to necking.

At necker machines, a flange was formed on the top rim of the 

cans. The flange was used to form the seal with the top of the 

cans during filling (a step not performed at this plant). The cans 

received a final check for damage and were then palletized and 

shipped to the customer. About 50 employees operated and 

maintained the printers, applicators, lacquer spray machines, 

and neckers. The area of the plant that includes the lacquer spray 

machines and neckers was referred to as the back end.

A 13,000-gallon central system supplied synthetic MWF for 

the ironer/trimmer lines. The Henkel DTI-I102B MWF (main 

ingredients included amine soaps, triethanolamine, and triazine) 

[Henkel 2007] was maintained under contract by Henkel Surface 

Technologies. The MWF sump had an automatic metering device 

to add coolant and water, and a fabric filter removed metal filings 

and other particulates. The biocide used at the plant, Rohm and 

Haas KathonTM 886, contained 5-chloro-2-methyl-4-isothiazolin3-one, 2-methyl-4-isothiazolin-3-one, magnesium nitrate, and 

magnesium chloride [Rohm and Haas 2009]. Biocide was manually 

added to the sump when necessary on the basis of level of bacteria 

in the MWF. The MWF system had been last emptied and cleaned 

on November 25, 2006.

Assessment

December 2008 Site Visit

We met with management and employee representatives to discuss 

the HHE. After the meeting, we toured the plant to observe 

work activities and the production process. We collected GA air 

samples on thermal desorption tubes to screen for volatile organic 

compounds and measured sound levels in production areas.

We selected for health interviews a convenience sample of three 

employees out of 20 employees from the printer area and all 14 

front end and maintenance employees who were present on the 

day of the first NIOSH site visit. These areas had been identified 

as having employees with skin rashes and respiratory problems. 

We asked about employment history, exposures, health symptoms, 

PPE use, and workplace safety and health concerns. We focused on 
Health Hazard Evaluation Report 2008-0099-3152 Page 3

Assessment

 (continued) interviewing this small group to obtain an indication of the types 

of problems that were occurring and to help determine, along with 

other factors, where a larger survey was needed.

We reviewed OSHA 300 Logs of Injury and Illness from 2004–

2008, first aid logs for 2008, and monthly accident reports for the 

last 3 years (2006–2008). We also reviewed the written respiratory 

protection and other safety programs, and we observed PPE use.

June 2009 Site Visit

We collected full-shift PBZ and GA air samples for MWFs at the 

front end, printer, and necker; sulfuric and hydrofluoric acids at 

the acid tank and can washer area; 2-dibutylaminoethanol at the 

printer; formaldehyde in all production areas; and endotoxin at the 

front end and printer. Formaldehyde and 2-dibutylaminoethanol 

were components of inks used for printing onto cans. Endotoxin 

can be a contaminant in used MWFs. We collected bulk samples 

of MWFs and submitted them for analyses for total bacteria, 

mycobacteria, fungi, and endotoxin. Air sampling methods are 

described further in Appendix A.

We measured full-shift personal noise exposures of 26 employees 

with Larson Davis (Provo, Utah) SparkTM Model 705P integrating 

noise dosimeters. We used a Larson Davis Model 824 integrating 

sound level meter and real time frequency analyzer equipped with 

a half-inch random incidence microphone (Type 1) for sound 

level and one-third octave band noise frequency measurement 

throughout production areas of the facility. Noise monitoring 

methods are further described in Appendix A.

We obtained an electronic database of 1,182 audiograms from 

1988 to 2008 for 104 current production employees. We analyzed 

employee audiometric test history to determine hearing threshold 

shift using OSHA and NIOSH criteria. For analysis, a hearing 

threshold shift was considered persistent when a minimum of 

two consecutive audiograms confirmed the threshold shift. We 

calculated material hearing impairment using NIOSH criteria. We 

also calculated the length of time between hire date and baseline 

audiogram, and the length of time between consecutive employee 

audiograms.
Page 4 Health Hazard Evaluation Report 2008-0099-3152

Assessment

 (continued)

Results

We asked all plant employees to complete a questionnaire to 

investigate possible associations between MWF exposure and 

dermatitis, respiratory symptoms, and PPE use. The questionnaires 

also asked about demographic information, pertinent medical 

history, and non-work exposures. We analyzed the questionnaire 

data using SAS Version 9.2. Details of the questionnaire analysis 

are described in Appendix A.

We classified our exposure groups on the basis of reported current 

job title of the participant. We classified the current job titles that 

were known to have exposures to MWF production work as the 

MWF-exposed group. This included all front end and back end 

employees in the production area who were known to have contact 

with MWF. We classified current job titles that were not exposed to 

MWF as the unexposed group. All administrative and office staff 

and employees involved in shipping and packaging (with minimal 

or no exposures to MWF) were included in the unexposed group.

We defined the following work-related symptoms: cough, wheezing 

or whistling in chest, unusual shortness of breath, chest tightness, 

nose irritation, eye irritation, sore throat, fever, and body aches 

by positive responses to both (1) having the symptom in the past 

month and (2) improvement on days away from work. We defined 

possible work-related asthma as a positive response to (1) ever had 

asthma, (2) still have asthma, and (3) does your asthma seem better 

when you are away from your current job. Symptoms suggestive 

of work-related asthma were defined as a positive response to 

work-related wheeze or two or more of the following symptoms: 

work-related cough, work-related chest tightness, or work-related 

shortness of breath in the past month as defined above. A personal 

history of allergic disease, or atopy, was defined as ever having a 

persistent itchy rash that affected skin creases (eczema or atopic 

dermatitis). We defined current work-related dermatitis as a 

positive response to (1) dermatitis on hands, wrists, or forearms in 

the last month; and (2) dermatitis is better when away from work.

Air and Bulk Sampling

A summary of air sampling results for MWFs and formaldehyde 

is provided in Tables 1 and 2. All air sampling results for MWFs, 

inorganic acids, formaldehyde, and 2-dibutylaminoethanol are 

presented in Appendix B, Tables B1–B4.
Health Hazard Evaluation Report 2008-0099-3152 Page 5

Results

 (continued) The MWF concentrations, as total thoracic particulate mass, were 

below the NIOSH REL-TWA of 0.40 mg/m3

. Exposures to total 

thoracic particulates and extracted MWFs were similar in the 

front end and printer areas. In addition, extracted MWFs were 

not detected in seven of the twelve PBZ air samples collected on 

employees working in the front end, or in three of the four air 

samples collected on printer operators. NIOSH does not have an 

REL-TWA for extracted MWFs.

We collected a full-shift PBZ air sample for hydrofluoric and 

sulfuric acid on an employee working near the can washer, 

hydrofluoric acid tank, and sulfuric acid tank. We also collected 

five GA air samples for hydrofluoric and sulfuric acids at these 

locations. One of the GA samples for hydrofluoric acid, collected 

near a hydrofluoric acid tank, had a TWA concentration of 

0.24 mg/m3

, which was below the REL-TWA of 2.5 mg/m3. The 

PBZ air sample and all the other GA air samples for hydrofluoric 

acid and sulfuric acid had measured concentrations that were 

either ND or below the MQC.

The results from the six PBZ samples for 2-dibutylaminoethanol 

collected on printer operators ranged from 0.20 to 0.26 mg/m3

, 

much lower than the NIOSH REL-TWA of 14 mg/m3

. The PBZ 

TWA concentrations for formaldehyde ranged from 0.020 to 

0.13 ppm, below the OSHA PEL of 0.75 ppm for an 8-hour TWA 

exposure [29 CFR 1910.1048]. However, these PBZ sample results 

Table 1. PBZ air sampling results for MWF, collected on June 9–10, 2009

Location/Job # Samples

Concentration (mg/m3

)

Total thoracic particulates*§ Extracted MWFs†§

Mean Range Mean Range

Front end 12 0.17 0.09–0.28 0.087 ND‡–0.19

Printer 4 0.15 0.09–0.27 0.098 ND‡–0.21

Necker 1 (0.070) NA¶ ND‡ NA¶

MDC 0.03 0.06

MQC 0.098 0.18

NIOSH REL 0.40 NA

*The total thoracic particulates value includes all dust and other aerosols in the air that are in the thoracic size 

range.

†The extractable fraction represents the portion of the sample that was MWF.

‡ND = not detected (below the MDC).

§Concentrations between the MDC and MQC are shown in parentheses to point out that there is more 

uncertainty associated with these values than with concentrations above the MQC.

¶NA = not applicable
Page 6 Health Hazard Evaluation Report 2008-0099-3152

Results

 (continued) exceed the NIOSH REL for formaldehyde of 0.016 ppm [NIOSH 

1977]. Printer operators had the highest exposure to formaldehyde. 

Two printer operators were exposed to formaldehyde 

concentrations greater than 0.1 ppm, the concentration at which 

OSHA requires employee notification and training.

Table 2. PBZ air sampling results for formaldehyde, collected on June 9–10, 2009

Location/Job # Samples Concentration (ppm)

Mean Range

Front end 11 0.044 0.023–0.090

Printer 5 0.098 0.071–0.13

Chemical process operator 2 0.026 0.020–0.031

Millwright 1 0.040 NA*

Forklift operator 1 0.080 NA

Lacquer spray 1 0.042 NA

NIOSH REL-TWA 0.016

OSHA PEL-TWA 0.75

* NA = not applicable (one sample collected)

We collected 16 PBZ air samples for endotoxin. Concentrations 

ranged from 0.23 to 2.2 EU/m3

. The concentration in a 

background sample collected outdoors was 1.1 EU/m3

. No 

accepted occupational exposure limits have been developed in the 

United States because of the variability of sampling and analytical 

methods and because of a lack of data showing a consistent 

dose-response relationship between exposures and health effects. 

In 2010, the Dutch Expert Committee on Occupational Safety 

recommended a health-based occupational exposure limit for 

airborne endotoxin of 90 EU/m3

 [DECOS 2010]. Endotoxin air 

sampling results are presented in Appendix B, Table B5.

Endotoxin concentrations ranged from 46 to 74 EU/mL in the 

five bulk MWF samples collected, with a mean concentration of 

62 EU/mL. Although there are no guidelines for acceptable levels 

of endotoxin in MWFs, these concentrations are lower than the 

average concentrations researchers have reported for endotoxin 

in MWFs at other companies [Simpson et al. 2003; Cyprowski et 

al. 2007]. Five MWF bulk samples were analyzed for bacteria and 

fungi. Neither mycobacteria nor fungi were detected in any of the 

samples. Total bacteria counts ranged from 1 to 100 CFU/mL for 

Bacillus species and 0 to 2 CFU/mL for aerobic actinomycetes. 

These are well below a concentration of one million CFU/mL of 

MWF, a level suggested by some researchers as appropriate for wellmaintained MWFs [Rossmore and Rossmore 1994].
Health Hazard Evaluation Report 2008-0099-3152 Page 7

Results

 (continued) Noise

Table 3 summarizes personal noise exposure measurements. 

Employees in the job titles front end maintenance/repair and 

millwright worked 8-hour shifts. Employees in the other job titles 

worked 12-hour shifts. All 26 of the personal noise exposure 

measurements exceeded the NIOSH REL of 85 dBA for an 8-hour 

work shift and 83.2 dBA when adjusted for a 12-hour work shift. 

Four of five TWA noise exposure measurements for printer 

operators and three of four TWA measurements for back end 

operators (necker and lacquer spray areas) exceeded 100 dBA.

Because OSHA uses different noise measurement criteria 

than NIOSH, TWA noise exposures for employees in the job 

titles material handler, millwright, palletizer, and front end 

maintenance/repair did not exceed the PEL. However, employees’ 

noise exposures in all of the job titles monitored exceeded the 

OSHA AL of 85 dBA for an 8-hour work shift and 82.1 dBA for 

a 12-hour work shift. Table B6 in Appendix B provides detailed 

personal noise monitoring results.

Table 3. Range of personal noise dosimetry measurements

Job title Number of 

measures

TWA noise measurements (dBA)

OSHA AL OSHA PEL NIOSH REL

Back end operator (lacquer spray) 2 97.5 – 99.0 97.4 – 98.9 98.8 – 100.5

Back end operator (necker) 2 99.9 – 99.9 99.8 – 99.9 102.2 – 102.7

Baler room/forklift operator 2 94.9 – 95.6 94.6 – 95.4 95.6 – 97.0

Front end ironer/trimmer 8 91.3 – 97.7 90.6 – 97.6 93.4 – 99.9

Front end maintenance/repair* 1 86.3 88.6 91.0

Material handler 2 81.3 – 87.3 71.2 – 81.8 84.2 – 89.8

Millwright* 2 87.7 – 89.8 84.3 – 87.4 90.7 – 93.4

Palletizer 2 85.6 – 86.9 72.5 – 77.3 86.6 – 88.0

Printer operators 5 98.2 – 100.2 98.2 – 100.0 99.7 – 101.2

Noise exposure limits

12-hour work shift 82.1 90.0 83.2

*8-hour work shift 85.0 90.0 85.0

* Employees in the job titles front end maintenance/repair and millwright worked 8-hour work shifts.
Page 8 Health Hazard Evaluation Report 2008-0099-3152

We measured one-third octave band noise levels at the cupper 

presses, ironers, printers, neckers, lacquer spray machines, and 

balers. At the cupper presses and ironers the predominant noise 

frequencies were 315 to 500 Hz. We found multiple peaks in low 

and high frequencies at the necker and lacquer spray machine. 

Similarly, the baler had multiple frequency peaks, but all were 

below 1,000 Hz, with 125 Hz being the dominant frequency. The 

dominant frequency for the printer was 10,000 Hz. A separate and 

very distinct peak of approximately 800 Hz occurred at the printer 

when the printer alarm sounded. Octave band measurement 

results are shown in Figures B1–B6 in Appendix B.

An analysis of the audiometric history for the 104 production 

employees for whom we had historic audiometric test results 

indicated that 43 (41%) had experienced an STS since their 

baseline audiogram on the basis of OSHA STS criteria. Using 

NIOSH hearing threshold shift criteria, 51 employees (49%) had 

experienced a hearing threshold shift. Appendix C explains the 

difference between the OSHA and NIOSH threshold shift criteria. 

Audiograms for 15 employees (14%) showed they had material 

hearing impairment on the basis of the NIOSH definition, which 

is an average HTL for both ears of 25 dB at 1,000, 2,000, 3,000, 

and 4,000 Hz [NIOSH 1998b]. Six additional employees also had 

material hearing impairment. However, these employees had this 

hearing loss at the time of hire.

We analyzed the time between employees’ hire date and the date of 

their first audiogram. Because the company started an audiometric 

testing program in 1988, only employees with a hire date of 1988 

or later (N=70) were included in this analysis. Results are shown in 

Table 4. Of these 70 employees, 43% had audiometric tests within 

6 months of hire, but 17% had their first audiometric test more 

than 1 year after hire.

Results

 (continued)

Table 4. Time between employee’s hire date and first audiometric test (only employees hired after 1988 

included, N=70)

Time between hire date and first audiogram Number of employees (%)

≤ 6 Months 30 (43)

> 6 Months and < 12 Months 28 (40)

≥ 12 Months 12 (17)

Average = 247 days (Range: 7–1569 days)
Health Hazard Evaluation Report 2008-0099-3152 Page 9

Results

 (continued) We separately analyzed the time between consecutive audiograms 

(N=1182) for each employee in the dataset (Figure 1). Approximately 

25% of audiometric tests were completed within 12 months of the 

previous test, as required by OSHA. More than 12 months elapsed 

between consecutive tests for about 75% of all audiometric tests. 

However, most of these were completed within 12 to 15 months of 

the previous audiometric test. For 4% of audiometric tests, more 

than 2 years elapsed between consecutive tests.

Figure 1. Months between consecutive 

audiograms (N=1,182).

Employee Interviews and Review of Injury 

and Illness Recordkeeping Logs

In December 2008, we interviewed a convenience sample of 17 

employees (three employees from the printer area and all 14 front 

end and maintenance employees). These areas had been identified 

as having employees with skin rashes and respiratory problems. 

Six reported skin rash to the wrist, arms, and hands that improved 

when they were away from work; three reported acute upper 

respiratory symptoms that improved when they were away from 

work; three reported hearing loss symptoms; and one employee 

reported recurring headaches that improved when away from work. 

In addition to health symptoms, employees also reported lack of 

safety communication, inadequate training, need for improved 

housekeeping to minimize slips and trips in the front end area, and 

general safety issues.

An incident log maintained by the plant had 29 incidents recorded 

in 2006, 27 in 2007, and 31 in 2008 that resulted in injuries or 

were considered near misses. Each entry included a short-term and 

long-term action plan to prevent future incidents. We reviewed the 
Page 10 Health Hazard Evaluation Report 2008-0099-3152

incident log from 2008 for injuries or illnesses that required first 

aid from the safety staff; four entries were recorded for skin rash 

and six for falls, abrasions, and slips/trips.

Our review of the OSHA 300 Logs from 2004–2008 revealed 

two reports of skin rashes from front end employees and eight 

reports of STS. The employees with STS did not have a common 

occupation or work area. All other entries on the OSHA 300 

Logs were injuries; specifically, 24 sprains/strains, 9 lacerations, 

2 crushing/smashing injuries, 2 eye injuries, and 2 contusions. 

Employees in maintenance and machinists were the most 

frequently injured.

Written Safety and Health Programs

Respiratory Protection 

Employees in the respiratory protection program were fitted to 

wear North (Cranston, Rhode Island) model 7700 half-mask 

elastomeric respirators. The written respiratory protection program 

lacked information on the chemical hazards present, anticipated 

concentrations, and specific type of respirator needed for these 

chemicals or hazardous conditions. The written program also did 

not include a cartridge or canister change-out schedule to ensure that 

employees replaced cartridges before the end of their service life. 

Personal Protective Equipment

The company had a written personal protective equipment 

certification of hazard assessment, as required by OSHA. All 

employees were required to wear safety glasses, safety shoes, and 

hearing protection. The company provided work uniforms (short 

or long sleeve shirts and pants), which some employees wore. 

However, some employees told us that because they were required 

to pay for cleaning the work uniforms, they chose not to wear the 

uniforms and wore their own clothes, typically jeans and T-shirts.

Some employees voluntarily wore nitrile gloves (Flexshield®) 

while changing tools on the ironer/trimmers or when handling 

chemicals. A concern noted by employees was the limited selection 

of glove sizes. The employees maintaining the can washers wore 

polyvinyl chloride gloves, a Tychem® suit, and steel-toe rubber 

boots because they could contact hydrofluoric and sulfuric acid. 

Employees adding chemicals to the water treatment tank or adding 

biocide to the MWF sump wore a rubber apron and rubber or 

Results

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 11

nitrile gloves. Durapro® barrier cream was available for employees 

at their workstations and from the storage room.

Hearing Conservation Program

The company had a written hearing conservation program that 

included information on noise monitoring, audiometric testing, 

hearing protection, and training. Employees were provided with 

Aearo (Indianapolis, Indiana) EAR Classic® and EAR Earsoft 

Superfit® foam insert type earplugs. The earplugs have a noise 

reduction rating of 29 dB and 33 dB, respectively. The company 

contracts a mobile audiometric testing provider to complete 

audiometric testing. The contractor provides the company with 

an audiometric test history report for each employee. The report 

notes individual trends, such as an OSHA STS. If the audiologist 

reviewing test results notes something unusual in an employee’s 

audiogram, such as asymmetrical hearing loss, the company is 

provided with an “audiologist review report” for use during further 

evaluations. Follow-up testing, if necessary, was usually done at 

a local clinic. Basic hearing conservation training was provided 

by the audiometric testing contractor while site-specific training, 

including instructions on proper fitting of hearing protection, was 

provided by the company safety director.

Health Questionnaire

During the site visit in June 2009, 128 out of 148 (86%) available 

plant employees completed the questionnaire. Fewer than 10 

employees were not at work because of vacation or sick leave.

Table 5 presents the characteristics of the MWF exposed and 

unexposed groups. Other than sex, demographics were similar 

between both groups.

Table 5. Demographic characteristics among MWF-exposed and unexposed employees

Characteristic

MWF-exposed

(N = 101)

Number (%)

Unexposed

(N = 27)

Number (%)

Male 92 (91) 17 (63)

Personal history of atopy* 7 (7) 1 (4)

Age – average 44 Years 48 Years

Total years at plant – average 13 Years 9 Years

*Positive responses to ever having a persistent itchy rash that affected skin creases (eczema or atopic dermatitis)

Results

 (continued)
Page 12 Health Hazard Evaluation Report 2008-0099-3152

Work-Related Respiratory Symptoms Among 

Plant Employees

Table 6 compares the prevalence of work-related symptoms 

in MWF-exposed and unexposed groups. Employees exposed 

to MWF reported few symptoms. Of reported symptoms, eye 

irritation had the highest prevalence. We did not find statistically 

significant differences in the prevalence of work-related symptoms 

in employees exposed to MWF compared to those unexposed 

to MWF. Four employees exposed to MWF reported that they 

had current work-related dermatitis. We looked at the prevalence 

of current work-related dermatitis in those exposed to MWF 

compared to those unexposed to MWF. We did not find a 

statistically significant difference.

Table 6. Prevalence of work-related symptoms among MWF-exposed and unexposed employees

Work-related 

symptoms*

MWF-exposed 

(N = 92–101)†

Number (%)

Unexposed 

(N=26–27)†

Number (%)

Prevalence ratio¶

(P value)

Cough 8 (8) 4 (15) 0.26 (0.25)

Wheeze 1 (1) 3 (12) 0.02 (0.003)

Shortness of breath 5 (5) 2 (8) 0.63 (0.58)

Chest tightness 4 (4) 2 (8) 0.60 (0.42)

Nose irritation 14 (14) 6 (23) 0.24 (0.26)

Eye irritation 10 (10) 3 (12) 0.72 (0.81)

Sore throat 3 (3) 2 (8) 0.27 (0.27)

Fever 0 2 (8) 0.04 (0.005)

Body aches 6 (6) 4 (15) 0.21 (0.11)

Asthma‡ 2 (2) 2 (7) 0.20 (0.15)

Symptoms suggestive of 

asthma§ 3 (3) 3 (12) 0.10 (0.07)

Dermatitis 4 (4) 0 0.57 (0.27)

*Positive responses to both: (1) having the symptom in the past month and (2) did it improve on your days off. 

†Range of denominators, i.e., the number of employees answering each question differed.

‡Positive responses to (1) ever had asthma, (2) still have asthma, and (3) does your asthma seem better when 

you are away from your current job.

§Positive responses to work-related wheeze, or two or more of the following symptoms: work-related cough, 

work-related chest tightness, or work-related shortness of breath in the past month. 

¶The prevalence ratio is defined as the prevalence of a symptom reported by MWF-exposed employees divided 

by the prevalence of symptom reported by MWF-unexposed employees.

Results

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 13

Dermatitis Among Plant Employees

Of 128 employee participants, 25 (16%) reported having had 

dermatitis on their hands, wrists, or forearms since they began 

working at the plant. Nine employees reported that they had seen a 

doctor for their dermatitis. Summer was the most common season 

when employees reported dermatitis. Employees reported what jobs 

they were working in when they first developed dermatitis. Of the 

24 jobs reported, most were in the printer (8) and front end (7) 

areas. Eight employees reported that contact with oil residue on 

metal parts, coolants or machining fluids, and lubricants in their 

work made their dermatitis worse, and four employees reported 

solvents made their dermatitis worse. Of the 14 employees who 

reported using gloves at work before they developed dermatitis, 

five reported that they changed glove type or stopped using gloves 

because of their dermatitis. Table 7 describes PPE use and hygiene 

practices among the employees exposed to MWF.

Table 7. Describing PPE use and hygiene practices among MWF-exposed employees

Reported PPE use and hygiene practices

MWF-exposed employees

(N =72–101)*

Number (%)

Use gloves at work 87 (86)

Use double glove† (among glove users) 22 (26)

Reuse disposable gloves‡ (among glove users) 1 (1)

Use protective sleeves 9 (9)

Average number of times hands washed at work 14

Apply moisturizing skin lotion 20 (20)

Apply barrier creams 12 (12)

Wet hands 2 hours or more/shift 36 (36)

*Range of denominators, i.e., the number of employees answering each question differed

†Using two pairs of the same glove at the same time

‡Current reuse of black latex or blue neoprene gloves

Other Findings

Following our initial site visit, the plant installed drip gutters 

beneath the conveyor lines between the ironers and trimmers to 

catch excess MWF from cans. This was an excellent application of 

engineering controls. However, we did observe MWF leaking at 

some of the ironers during our return visit (Figures 2 and 3).

Results

 (continued)
Page 14 Health Hazard Evaluation Report 2008-0099-3152

We observed walking surfaces that were slippery from MWF 

in the ironer area (Figure 4) and on the short metal grating 

platforms used for stepping over the can conveyor lines. The 

stair steps for the wastewater treatment platform (Figure 5) were 

slippery from chemical residue used for the wastewater treatment 

tanks. We observed water on the floor (Figure 6) near the water 

fountain between the Concord printers. The water dripping from 

the platform above appeared to be dripping onto an electrical 

panel box. We informed management of this water leak during 

the site visit.

During our second site visit, we observed that employees could 

reach into or enter the palletizer to retrieve stray cans while 

the machine was still operating. This potential safety hazard 

resulted from an incorrect location of the automatic shut-off 

light sensors. We also noted that the palletizer system could lose 

air pressure while it was locked out for repair, resulting in the 

top frame carriage potentially falling and trapping or injuring an 

employee. We informed management of this safety hazard during 

the site visit.

Some work areas where acids were located did not have emergency 

eyewash stations or showers. This was noted in the tank farm 

building and near the outdoor tanks of sulfuric acid and 

hydrochloric acid. The chemical storage room where 12 330-gallon 

totes of hydrofluoric acid were stored had an eyewash station, 

but did not have an emergency shower. We observed that the 

eyewash in the washer and dryer area was not working correctly. 

The left nozzle had low water flow unless the activation paddle was 

completely depressed. However, when the paddle was completely 

depressed the water flow appeared to be excessively strong through 

the left nozzle.

We observed that steam was not captured by the exhaust hood at 

some of the ironers. The effectiveness of the exhaust ventilation 

system at the ironers was decreased by the use of flexible 

duct, which has greater air flow resistance than smooth duct. 

Additionally, some ductwork had unnecessary bends that also 

reduced the overall effectiveness of the exhaust ventilation system 

(Figure 7). We also saw a hole in the bottom of the ventilation duct 

near the top of Cure Oven 1.

The labels on some storage tanks in the washer area did identify 

the contents as acids. Some containers in one of the quality control 

labs did not include hazard warning information, as is required 

Figure 3. MWF overflowing from 

an ironer.

Figure 4. Metalworking fluid on floor in 

ironer area.

Figure 2. Leaking MWF at an ironer.

Results

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 15

by the OSHA hazard communication standard (Figure 8). We saw 

other tanks without hazard warning information, including the 

tramp oil tank in the bulk storage room.

We observed that some forklift drivers did not consistently wear 

seat belts.

Figure 5. Stairs at mezzanine of wastewater 

treatment area were noticeably 

slippery.

Figure 6. Water on floor near Concord 

printers.

Figure 7. Flexible exhaust ventilation duct with 

too many bends at an ironer, which 

reduces effective ventilation.

Figure 8. Labels on containers of alcohol in 

a quality control lab did not include 

hazard information to warn users of 

possible adverse health effects from 

the product.

Results

 (continued)
Page 16 Health Hazard Evaluation Report 2008-0099-3152

Discussion

Air Contaminants

Our sampling results indicated that employees were 

not overexposed to airborne MWFs, inorganic acids, 

dibutylaminoethanol, or endotoxin during this evaluation. 

However, even small amounts of these substances can irritate 

the skin and cause dermatitis [Blanc et al. 1991; Lee et al. 1997; 

Rosenberg et al. 1997; NIOSH 1998a; Godderis et al. 2008]. 

Information on the health hazards associated with MWF and 

formaldehyde is provided in Appendix C.

The MWF bulk samples we collected from the sump and the 

ironer/trimmer machines contained low levels of bacteria and 

endotoxin. Additionally, our review of the results from previous 

testing completed by Henkel Surface Technologies revealed that 

bacteria and fungi were not detected in samples collected between 

January 2007 and November 2008, on the basis of dipstick testing 

methods (limit of detection not specified in test reports). The pH 

ranged from 8.9 to 9.4, and tramp oils ranged from 1.3% to 3.6%. 

This suggests that the MWF system was well maintained. We noted 

that employees manually added Kathon 886TM biocide to the MWF 

sump if high levels of bacteria were detected. Installing a metered 

dispenser to add biocide to the sump would reduce the risk of 

employee exposure from manual application.

Formaldehyde concentrations were well below the OSHA PEL 

of 0.75 ppm, but did exceed the NIOSH REL of 0.016 ppm. 

This REL was established in 1981 when NIOSH recognized 

formaldehyde as a potential occupational carcinogen. On the basis 

of the carcinogen policy in existence at the time, NIOSH set the 

REL to the “lowest feasible concentration,” which for formaldehyde 

was defined as the analytical limit of quantification of 0.016 ppm 

for up to a 10-hour TWA and a ceiling limit of 0.10 ppm that 

should not be exceeded [NIOSH 1981]. However, research has 

shown that concentrations of formaldehyde in ambient air can 

approach or exceed this level [Lemen 1987]. Additionally, the 

subsequent revision of the NIOSH carcinogen policy [NIOSH 

1995], combined with better exposure characterization and 

advances in risk assessment and management strategies, support 

the need for NIOSH to reassess the formaldehyde REL.
Health Hazard Evaluation Report 2008-0099-3152 Page 17

Noise Exposures

OSHA and NIOSH use different criteria for measuring TWA 

noise exposures. Although not all employees were exposed to noise 

levels that exceeded the OSHA PEL of 90 dBA, all monitored 

employees’ noise exposures exceeded the OSHA AL and NIOSH 

REL. The NIOSH REL for noise is not a legally enforceable noise 

exposure limit; however, it is more protective than the OSHA PEL 

in preventing hearing loss.

More than 57% of employees had their first, or baseline, 

audiogram more than 6 months after their hire date, and 17% 

had their baseline audiogram more than 1 year after they were 

hired. Completion of baseline audiograms before newly hired 

employees begin working allows identification of hearing loss prior 

to workplace noise exposures. If hearing loss is identified on an 

audiogram completed after a new employee has begun working, 

the source of the hearing loss cannot be determined because it may 

have been present prior to workplace exposure or have occurred 

after the employee began working.

Our analysis of employee audiograms showed that 15 employees 

(14%) had hearing loss that met the NIOSH definition of material 

hearing impairment. Previous NIOSH research has shown that 

employees with noise exposures greater than 85 dBA are at risk of 

hearing loss in as little as 5 to 10 years of exposure. Figures 9 and 

10 present NIOSH research estimates for excess risk of material 

hearing impairment, on the basis of age and duration of exposure 

[NIOSH 1998b].

Discussion

 (continued)

Figure 9. NIOSH excess risk estimates (%) for material hearing 

impairment, by age, after 5 to 10 years of noise exposure.
Page 18 Health Hazard Evaluation Report 2008-0099-3152

Our analysis of the audiometric history for 104 current production 

employees indicated that 41% had an OSHA-defined STS, and 

49% had a NIOSH-defined hearing threshold shift since their 

baseline audiogram. The reason for this difference is that NIOSH 

includes hearing loss in all audiometric test frequencies, whereas 

OSHA only uses the frequencies 2, 3, and 4 kHz.

Figure 11 shows the audiometric history for one of the production 

employees. The figure shows a characteristic notch at 4 kHz 

representing a common NIHL audiogram pattern. Figure 12 

also shows the audiometric history for a different production 

employee. However, the audiograms in this figure show substantial 

hearing loss at 6 kHz, rather than 4 kHz. Although NIHL is 

typically first observed in the 4 kHz and 6 kHz audiometric test 

frequencies, interpretation of the audiograms in Figure 13 is 

somewhat challenging because an audiogram showing progressively 

increasing HTLs with increasing audiometric test frequencies can 

also indicate presbycusis (age-related hearing loss). Inclusion of the 

8 kHz frequency in audiometric testing would allow detection of 

a notch at 6 kHz and provide better information for audiologists 

or physicians reviewing audiograms to interpret hearing loss in 

audiometric test results. Additionally, if the audiometric testing 

program only uses OSHA STS criteria and does not track hearing 

levels at 6 kHz or 8 kHz, employees with progression of NIHL at 

6 kHz may not be identified or their NIHL may not be detected 

until the hearing loss has also progressed substantially at 4 kHz. 

This could delay important intervention to prevent further hearing 

losses. Therefore using both OSHA and NIOSH criteria for 

evaluating threshold shifts among the employees is advisable.

Discussion

 (continued)

Figure 10. NIOSH excess risk estimates (%) for material hearing 

impairment, by age, after more than 10 years of noise 

exposure.
Health Hazard Evaluation Report 2008-0099-3152 Page 19

Several employees’ audiograms showed year-to-year variation in 

HTLs. Although variation of 5 to 10 dB in HTL from one year 

to the next is common, an improvement in HTL greater than 10 

dB is not typical. There may be several reasons for this variability. 

Because audiograms were conducted during the work shift, some 

of the employees may have had a temporary threshold shift at 

the time of an audiogram, but did not have one for the next 

audiogram. A temporary threshold shift can occur if employees 

wear no hearing protection before the audiogram or their hearing 

protection was not properly worn and allowed substantial noise 

to reach the ear. OSHA requires that employees not be exposed 

to noise levels greater than 85 dBA for at least 14 hours before an 

Discussion

 (continued)

Figure 11. Audiometric history showing typical NIHL pattern at 4 kHz.

Figure 12. Audiometric history showing substantial hearing loss at 6 kHz.
Page 20 Health Hazard Evaluation Report 2008-0099-3152

audiogram. NIOSH recommends that employees have at least 12 

hours of unprotected quiet before an audiometric test. Alternatively, 

any background noise during the employee’s audiometric test could 

produce an artificially high HTL for that particular test. OSHA 

specifies the maximum noise limits inside the audiometric test 

booth during a test. Additionally, different audiometers used from 

one year to the next can yield different results.

Our analysis was limited to the 104 current production employees 

for whom we had audiometric records and did not include former 

employees from the period 1988 to 2008. Although the audiograms 

we evaluated show that some employees have experienced threshold 

shifts and hearing loss, our analysis does not reveal whether the rate 

of threshold shifts has changed over time. Additionally, we did not 

include age correction adjustments to the audiograms. Therefore, 

the number of threshold shifts we identified is likely higher than 

would be identified if OSHA age correction criteria were applied. 

NIOSH does not recommend that age correction be applied to an 

individual’s audiogram for threshold shift calculations [NIOSH 

1998b]. Some, but not all, people experience some decrease in 

hearing sensitivity with age. It is not possible to know who will 

and who will not have an age-related hearing loss. Thus, applying 

age corrections individually to calculate a significant hearing 

threshold shift tends to overestimate the expected hearing loss for 

some and underestimate it for others because the median hearing 

loss attributable to presbycusis for a given age group will not be 

generalizable to that experienced by an individual in that age group. 

However, some researchers support the practice of age correction 

because not all hearing loss experienced by employees is a result 

of noise exposures, and advocate an expert professional review of 

audiograms to avoid categorization that all hearing changes are 

work-related [Royster 2000].

Although all company employees wore foam insert hearing 

protection, some did not insert them deeply enough in the 

ear canal. Additionally, employees can appear to have hearing 

protection properly inserted but it may not fit effectively. Given 

these observations and the analysis of audiograms indicating 

hearing loss, it is important for the company to emphasize 

consistent and proper use of hearing protection. Methods for 

fit testing of hearing protection are also available from some 

manufacturers to help ensure proper selection and adequate fit of 

hearing protection.

Discussion

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 21

Some or all of the monitored employees in the job titles lacquer 

spray operator, necker operator, and printer operator had TWA 

noise exposures greater than 100 dBA. No employees were 

observed wearing earmuffs during the HHE. Some employees 

expressed reluctance to use earmuffs, particularly during warm 

weather, because they sweat around their ears and the earmuffs 

become very uncomfortable.

Octave band noise frequency analysis revealed that some equipment 

had the highest noise levels at low frequencies. Noise reduction 

strategies for low frequency noise should focus on reducing 

equipment vibration. For example, installation of appropriately 

designed vibration isolation pads or springs can reduce vibration 

transmitted from operating equipment to surrounding surfaces 

(Figure 13). Replacing thin metal panels with thicker metal or 

dampened metal panels can also help reduce vibration.

Discussion

 (continued)

Figure 13. Large cupper press, without vibration damping, mounted to 

the concrete floor.

High frequency noise can be reduced by using acoustic equipment 

enclosures or noise barriers (Figures 14). For example, properly 

designed equipment enclosures may be suitable for the lacquer 

spray machine, printer, necker, and baler. If space and production 

logistics allow, it may be possible to construct operating booths 

for employees to use when they are not working directly at 

production equipment. Although most noise results from 
Page 22 Health Hazard Evaluation Report 2008-0099-3152

equipment operation, some noise could result from lack of timely 

maintenance. For example, high frequency squeaks noticeable 

near the backside of the some printers could be eliminated by 

lubrication of the equipment. We observed loose panels at the 

ironers that, if tightened, would eliminate unnecessary rattling.

Because effective noise engineering controls can be challenging to 

design and implement, noise reduction should be considered as 

part of an overall long-term strategy. For example, when equipment 

is replaced, the amount of noise generated by the new equipment 

should be considered as part of the purchasing decision. It may 

also be helpful to consult with an experienced noise control 

engineer to help design noise controls.

Discussion

 (continued)

Figure 14. Motor and blower, without vibration isolation or noise 

enclosure, mounted directly to a metal platform above the 

necker line.

Health Questionnaires and Interviews

Because of the open layout of the manufacturing areas, many of 

the production and maintenance employees could be exposed to 

MWF. However, our analysis of the questionnaire and interview 

responses revealed few MWF-exposed employees who reported 

respiratory symptoms. We did not find a statistically significant 

relationship between MWF exposure and work-related respiratory 
Health Hazard Evaluation Report 2008-0099-3152 Page 23

symptoms. In addition, employees in work areas such as near the 

printer and lacquer spray machines areas could be exposed to 

paints, printing inks, and solvents that could be related to health 

outcomes of interest in this evaluation. Other employees such as 

those working in the shipping/receiving area and administrative 

area would not be exposed to MWF.

We found no statistically significant increase in current workrelated dermatitis in employees exposed to MWF compared to 

those unexposed to MWF. Few employees reported current workrelated dermatitis, and few reports of skin rash were reported in 

the interviews. Of the 16% of employees reporting dermatitis since 

starting employment at the plant, we were unable to determine if 

past symptoms were work-related. Of those with existing irritant 

and allergic contact dermatitis, symptoms can become worse when 

exposed to MWF or machining oils, formaldehyde, or solvents 

[NIOSH 1998a, Chew and Maibach 2003; Slodownik et al. 2008, 

Warshaw et al. 2007, 2008].

In addition to MWF exposure, some employees (36%) reported 

that they had wet hands for 2 hours or more, defined as exposure 

of skin to liquid for more than 2 hours per day. Wet hands, use of 

water resistant gloves for more than 2 hours per day, or frequent 

hand washing, are the most common causes for skin irritation 

[Chew and Maibach 2003; Slodownik et al. 2008]. Few employees 

used lotions or barrier creams or wore long sleeves, actions that 

are known to help prevent the irritant effects from MWF [NIOSH 

1998a]. More information about exposures that contribute to 

contact dermatitis can be found in Appendix C. We found 

that most employees exposed to MWF used gloves, but a lower 

percentage of employees reported using protective sleeves and 

moisturizing lotions (Table 3).

The findings from these questionnaires and interviews should 

be carefully interpreted because the information may not be 

representative of all plant employees. Although we achieved a 

high participation rate of 86% and we randomly selected staff 

to interview, participation was voluntary and some employees 

declined to participate. Also, employees away from work on the day 

we offered the interviews or questionnaire are not represented in 

these results.

Discussion

 (continued)
Page 24 Health Hazard Evaluation Report 2008-0099-3152

Other Findings

On the days of the June 2009 site visit the temperatures in the 

plant were above 90°F; therefore, during the summer, employees 

could be at risk for heat-related illness. In addition, summer was 

the season that employees reported the most problems with hand, 

wrist, or forearm dermatitis. Heat disorders and health effects 

in individuals exposed to hot working environments include (in 

increasing order of severity) skin disorders (heat rash, hives, etc.), 

fainting, heat cramps, heat exhaustion, and heat stroke. Fainting 

results from blood flow being directed to the skin for cooling, 

resulting in decreased supply to the brain. This most often 

happens to employees who stand in place for extended periods 

in hot environments. Heat cramps, caused by sodium depletion 

due to sweating, typically occur in the muscles during strenuous 

work. Heat exhaustion symptoms include weakness, fatigue, 

confusion, nausea, chills, and others. Heat cramps and fainting 

often accompany heat exhaustion. The level of heat stress at which 

health effects occur is highly individual and depends upon the heat 

tolerance capabilities of each individual [NIOSH 1986].

Age, weight, degree of physical fitness, degree of acclimatization, 

metabolism, alcohol or illicit drugs, over the counter and 

prescribed medications, and a variety of medical conditions, 

such as hypertension and diabetes, all affect a person’s sensitivity 

to heat. At greatest risk are un-acclimatized employees, people 

performing physically strenuous work, those with previous heat 

illnesses, the elderly, people with cardiovascular or circulatory 

disorders (diabetes, atherosclerotic vascular disease), those taking 

medications that impair the body’s cooling mechanisms, people 

who use alcohol or are recovering from recent use, people in poor 

physical condition, and those recovering from illness.

Discussion

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 25

All production employees were overexposed to noise, 

and some employees may have noise-induced hearing 

loss. While all employees should be enrolled in a hearing 

conservation program, the printer, lacquer spray, and necker 

operators need to wear dual hearing protection (plugs and 

muffs) because of the extremely high noise levels present 

in their work areas. Employees were not overexposed to 

airborne MWFs, inorganic acids, dibutylaminoethanol, or 

endotoxin. However, two printer operators were exposed 

to formaldehyde above 0.1 ppm, the level at which OSHA 

requires employee notification and training. Few respiratory 

or skin symptoms were reported among employees exposed 

to MWF, and we did not find statistically significant 

increases in work-related respiratory or dermatitis symptoms 

in employees exposed to MWF.

Conclusions

Recommendations

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

below to create a more healthful workplace. We encourage the 

plant 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 plant. Our recommendations are 

based on the hierarchy of controls approach (refer to Appendix C: 

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.

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. We recommend the following 

engineering controls:
Page 26 Health Hazard Evaluation Report 2008-0099-3152

1. Install engineering controls at noisy equipment to reduce noise 

exposures. We recommend consulting with an acoustic engineer 

for specific guidance on noise control strategies.

2. Reduce exposures to MWFs by the following methods:

a. Reduce aerosolization of MWF from the ironer.

b. Repair MWF leaks.

c. Enclose the MWF operations as much as possible.

d. Use smooth walled exhaust ventilation duct (instead of 

flexible duct) and minimize bends in the duct to improve 

the overall capture efficiency.

e. Inspect the exhaust ventilation systems regularly to identify 

and repair corrosion, holes, and other problems.

3. Install a closed loop dispenser to add Kathon 886TM biocide to 

the MWF sump.

4. Replace hydrofluoric acid with a less hazardous chemical, if 

feasible. Hydrofluoric acid is extremely corrosive and can easily 

penetrate the skin and damage underlying tissue such as bone.

5. Ensure that emergency eye washes and showers are installed 

in areas where employees could have exposure to corrosive 

chemicals [29 CFR 1910.133(a)(1)].

6. Install leak detectors and audible alarms in areas where acids are 

stored.

7. Repair leaks to keep fluids from spilling onto walking surfaces or 

onto other surfaces. To prevent slipping, clean walking surfaces 

and steps promptly when leaks occur.

8. Adjust the automatic shut-off light sensors on the palletizer to 

prevent employees from entering the machine while it is still 

operating.

9. Secure the top frame carriage of the palletizer when making repairs.

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 

Recommendations

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 27

or production. We recommend you implement the following 

administrative controls:

1. Complete baseline audiograms before employees begin working, 

and repeat audiometric tests annually.

2. Use NIOSH and OSHA criteria for identifying hearing 

threshold shifts.

3. Include the 8 kHz frequency in audiometric tests.

4. Include all employees exposed to MWF above half of the 

NIOSH REL in the medical monitoring program. Even 

employees with less exposure to MWF may benefit from medical 

monitoring. See Appendix C for more information.

5. Educate employees to recognize the hazards of MWF exposure 

and to use work practices that prevent skin exposure to MWFs 

(Appendix C, Contact Dermatitis section).

6. Instruct employees not to use cleaning solvents to wash their 

hands or other parts of their body. These solvents remove 

protective oils in the skin, increasing the potential for skin 

irritation when employees come in contact with MWFs and 

other chemicals.

7. Encourage employees to report all potential work-related skin 

problems and respiratory problems to their supervisors so they 

can be evaluated, preferably by a healthcare provider familiar 

with occupational conditions.

8. Train employees on the health hazards associated with exposures 

to hazardous chemicals (such as hydrofluoric and sulfuric acid, 

biocides, and MWFs), what PPE is required when handling the 

chemicals, and what to do in the event of a spill. Refer to OSHA 

standard 29 CFR 1910.1200, hazard communication, for more 

information.

9. Provide training for printer operators on the health hazards 

associated with exposure to formaldehyde and the contents of 

the OSHA formaldehyde standard 29 CFR 1910.1048.

10. Improve the quality of safety and health training by conducting 

monthly interactive and comprehensive safety training sessions 

that include a question and answer period for employees to 

discuss safety and health issues openly.

11. Include information in the written respiratory protection 

program about the chemical hazards present, anticipated 

concentrations, and specific type of respirator needed. 

A cartridge or canister change-out schedule must also be 

included.

Recommendations

 (continued)
Page 28 Health Hazard Evaluation Report 2008-0099-3152

12. Label all containers and pipes containing hazardous chemicals 

to identify the contents and potential hazards of exposure to 

the chemicals.

13. Check emergency eyewashes and showers weekly to ensure 

proper function.

14. Take prompt action to correct safety and health problems 

identified and reported by employees or the safety and health 

committee. Follow-up action should be reported back to 

employees and documented in the safety and health committee 

meeting minutes.

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. Until employees 

exposures are eliminated or reduced below applicable OELs we 

recommend the following guidelines for use of PPE:

1. Provide dual hearing protection (ear plugs and earmuffs) for the 

printer and back end operators (necker and lacquer spray areas) 

where noise exposures exceed 100 dBA.

2. Make sure employees properly insert ear plugs.

3. Ensure that employees wear required PPE such as chemical 

protective gloves when in contact with coolants and acids.

4. Encourage employees to use moisturizer after washing hands, 

as well as before and after work, to prevent skin problems from 

MWFs and other chemicals.

5. Inform employees that skin barrier creams have not shown to be 

as effective as claimed in preventing penetration of irritants and 

avoiding hand dermatitis.

6. Encourage employees to use protective sleeves to prevent dermal 

exposure to MWFs and other chemicals.

Recommendations

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 29

Blanc PD, Galbo M, Hiatt P, Olson KR [1991]. Morbidity following 

acute irritant inhalation in a population-based study. JAMA 

266(5):664–669.

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Government Printing Office, Office of the Federal Register.

Chew AI, Maibach HI [2003]. Occupational issues of irritant 

contact dermatitis. Int Arch Occup Environ Health 76(5):339–346.

Cyprowski M, Piotrowska M, Zakowska Z, Szadkowska-Stańczyk I 

[2007]. Microbial and endotoxin contamination of water-soluble 

metalworking fluids. Int J Occup Med Environ Health 20(4):365–371.

DECOS [2010]. Endotoxins. health-based recommended 

occupational exposure limit. The Hague: Health Council of the 

Netherlands, Dutch Expert Committee on Occupational Safety. 

[http://www.gezondheidsraad.nl/sites/default/files/201004OSH.

pdf]. Date accessed: January 2012.

Godderis L, Deschuvffeleer T, Roelandt H, Veulemans H, Moeus 

G [2008]. Exposure to metalworking fluids and respiratory and 

dermatological complaints in a secondary aluminum plant. Int 

Arch Occup Environ Health 81(7):845–853.

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safety data sheet. [http://henkelconsumerinfo.com/products/

henkel.datasheets.Search.pdf?BUSAREA=0006&DOCTYPE=MS

DS&LANG=EN&COUNTRY=US&MATNR=596884&VKORG

=3450]. Date accessed: January 2012.

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DC [1997]. The prevalence of pulmonary and upper respiratory 

tract symptoms and spirometric test findings among newspaper 

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Lemen RA [1987]. Official letter from RA Lemen, Director, 

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Tom Hall, Docket Office, Department of Labor, Washington, DC, 

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NIOSH [1977]. Criteria for a recommended standard: occupational 

exposure to formaldehyde. Cincinnati, OH: U.S. Department of 

Health, Education, and Welfare, Centers for Disease Control, 

National Institute for Occupational Safety and Health, DHEW 

(NIOSH) Publication No. 77-126.

NIOSH [1981]. Current intelligence bulletin 34 – formaldehyde: 

evidence of carcinogenicity. 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. DHHS (NIOSH) 81-111 (1981, 

updated 1997). [http://www.cdc.gov/niosh/81111_34.html].

NIOSH [1986]. Criteria for a recommended standard: 

occupational exposure to hot environments. Cincinnati, OH: U.S. 

Department of Health and Human Services, Centers for Disease 

Control, National Institute for Occupational Safety and Health, 

DHHS (NIOSH) Publication No. 86-113.

NIOSH [1995]. NIOSH recommended exposure limit policy. 

September 1995. In: NIOSH policy statements. Cincinnati, 

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

for Disease Control and Prevention, National Institute for 

Occupational Safety and Health.

NIOSH [1998a]. Criteria for a recommended standard: 

occupational exposure to metalworking fluids. 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. 

98-102.

NIOSH [1998b]. Criteria for a recommended standard: 

occupational noise exposure (revised criteria 1998). 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. 

98-126.

Rohm and Haas [2009]. KathonTM material safety data sheet. 

[http://www.rohmhaas.com/wcm/products/product_detail.

page?display-mode=msds&product=1010127]. Date accessed: 

January 2012.

References

 (continued)
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Rosenberg J, Cone JE, Katz EA [1997]. Solvents. In: LaDou J, ed. 

Occupational and environmental medicine, 2nd rev. ed. Stamford, 

CT: Appleton and Lange, pp. 483–513.

Rossmore LA and Rossmore HW [1994]. Metalworking fluid 

microbiology. In: Byers J, ed. Metalworking fluids. New York: 

Marcel Dekker, Inc., pp. 247–271.

Royster JD [2000]. Audiometric monitoring phase of the HCP. In: 

Berger EH, Royster LH, Royster JD, Driscoll DP, Layne M, eds. 

The noise manual. 5th ed. Fairfax, Virginia: American Industrial 

Hygiene Association, pp. 455–516.

Simpson AT, Stear M, Groves JA, Piney M, Bradley SD, Stagg S, 

Crook B [2003]. Occupational exposure to metalworking fluid mist 

and sump fluid contaminants. Ann Occup Hyg 47(1):17–30.

Slodownik D, Lee A, Nixon R [2008]. Irritant contact dermatitis: a 

review. Australas J Dermatol 49(1):1–9.

Warshaw EM, Ahmed RL, Belsito DV, DeLeo VA, Fowler 

JF, Maibach HI, Marks JG, Mathias CG, Pratt MD, Rietschel 

RL, Sasseville D, Storrs FJ, Taylor JS, Zug KA [2007]. Contact 

dermatitis of the hands: cross-sectional analyses of North American 

Contact Dermatitis Group Data, 1994–2004. J Am Acad Dermatol 

57(2):301–314.

Warshaw EM, Schram SE, Maibach HI, Belsito DV, Marks JG, 

Fowler JF, Rietschel RL, Taylor JS, Mathias CG, DeLeo VA, Zug 

KA, Sasseville D, Storrs FJ, Pratt MD [2008]. Occupation-related 

contact dermatitis in North American health care workers referred 

for patch testing: cross-sectional data, 1998–2004. Dermatitis 

19(5):261–274.

References

 (continued)
Page 32 Health Hazard Evaluation Report 2008-0099-3152

Appendix A: Methods

Metalworking Fluid Air Samples

MWF air samples were collected using a 37-millimeter open-face three-piece cassette containing a tared 

2-micron pore-size polytetrafluoroethylene filter and a supporting pad mounted on a BGI (Waltham, 

Massachusetts) GK2.69 thoracic cyclone. The cassette was connected by Tygon® tubing to an SKC (Eighty 

Four, Pennsylvania) AirCheck® pump set at a nominal sampling rate of 1.6 Lpm. The samples were 

analyzed by gravimetric analysis for the thoracic fraction of MWF particulates per NIOSH Method 5524 

[NIOSH 2011].

Formaldehyde

Formaldehyde air samples were collected using SKC UMEX 100 passive badges (SKC #500-400, lot #5926) 

containing a sample strip and a reference strip impregnated with 2, 4-dinitrophenylhydrazine that forms 

dinitrophenylhydrazine-hydrazone when exposed to formaldehyde [SKC 2007]. The samples were analyzed 

for formaldehyde by OSHA Method 1007 [OSHA 2009]. The UMEX 100 badge has a measurement range 

of 0.005 to 5 ppm and a limit of detection of 0.002 ppm.

Inorganic Acids

Inorganic acid air samples were collected on silica gel tubes (SKC #226-10-03, lot #5727) connected by 

Tygon tubing to an SKC Pocket Pump® set at a nominal sampling rate of 0.20 Lpm. The samples were 

analyzed for sulfuric and hydrofluoric acid per NIOSH Method 7903 [NIOSH 2011].

Dibutylaminoethanol

Dibutylaminoethanol air samples were collected on 90-mg XAD-7 tubes (SKC #226-94, lot #4919) 

connected by Tygon tubing to an SKC Pocket Pump set at a nominal sampling rate of 0.050 Lpm. The 

samples were analyzed per NIOSH Method 2561 [NIOSH 2011].

Endotoxin in Air

Endotoxin (a component in the cell membrane of Gram-negative bacteria) air samples were collected on 

tared 5.0-micron pore-size, 37-millimeter polyvinyl chloride filters connected by Tygon tubing to an SKC 

AirCheck® pump set at a nominal sampling rate of 2.0 Lpm. The samples were weighed and analyzed 

for endotoxin content with the Kinetic-QCL instrumentation using the Limulus amebocyte lysate assay 

[Cambrex 2005]. For these analyses, 10 endotoxin units are equivalent to one nanogram of endotoxin. The 

limit of detection for this analysis was 0.005 endotoxin units per sample, which equates to a minimum 

detectable concentration of 0.02 EU/m3

 on the basis of a sample volume of 230 liters.
Health Hazard Evaluation Report 2008-0099-3152 Page 33

Appendix A: Methods (continued)

Noise 

Larson-Davis (Provo, Utah) Spark® 705P noise dosimeters were attached to the wearers’ belts, and 

small remote microphones were fastened to the wearers’ shirts at a point midway between the ear and 

the outside of the shoulder. Windscreens provided by the dosimeter manufacturer were placed over the 

microphones during measurements to reduce or eliminate artifact noise, which can occur if objects bump 

against an unprotected microphone. The dosimeters were set up to collect data using different settings to 

allow comparison of noise measurement results with the three different noise exposure limits referenced 

in this HHE, the OSHA PEL and AL, and the NIOSH REL. OSHA uses a 90-dBA criterion and a 5-dB 

exchange rate. The difference between the OSHA PEL and AL is the threshold level used for each. The 

PEL has a 90 dBA threshold and the AL has an 80 dBA threshold. NIOSH has an 85 dBA criterion and 

uses an 80 dBA threshold. During noise dosimetry measurements, noise levels below the threshold level 

are not integrated by the dosimeter for accumulation of dose and calculation of TWA noise level.

The dosimeters averaged noise levels every second during monitoring. The noise measurement 

information stored in the dosimeters was downloaded to a personal computer for interpretation with 

Larson Davis Blaze® computer software. The dosimeters were calibrated before and after the measurement 

periods according to the manufacturer’s instructions.

Area noise levels and octave band frequency spectrum analysis (measurement of noise in different 

frequencies) were measured with System 824 SLM and real-time frequency analyzers (Larson-Davis, Provo, 

Utah). The SLMs were equipped with 0.5-inch random incidence Type 1 electret microphones and the 

instruments measured noise levels between 16 and 150 dBA. The SLMs were calibrated before and after 

the measurement periods according to the manufacturer’s instructions. SLMs were either handheld or 

mounted on a tripod at a height of approximately 5 feet.

Statistical Analysis

Descriptive statistics including means, frequencies, and percents were calculated to summarize the 

questionnaire data. To compare prevalences of dermatitis between those in the MWF-exposed and MWFunexposed job categories, either the chi-square test or the Fisher’s exact test was used, and the prevalence 

ratio was reported. The prevalence ratio is defined as the prevalence of cough reported by MWF-exposed 

employees divided by the prevalence of cough reported by MWF-unexposed employees. Therefore, a 

prevalence ratio > 1 would indicate that a MWF-exposed employee might be more likely to report cough. 

For the statistical tests, a P value was also reported. If the P value is 0.05 or less, the result is described as 

statistically significant and one can confidently state that the result is not likely due to chance.
Page 34 Health Hazard Evaluation Report 2008-0099-3152

Appendix A: Methods (continued)

References

Cambrex [2005]. Limulus Amebocyte Lysate (LAL), Kinetic-QCL. Catalog Number: 50-650U. Walkersville, 

MD.

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, Public Health Service, 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/]. Date accessed: January 2012.

OSHA [2009]. Safety and health topics: Sampling guide. Washington, DC: Occupational Safety and 

Health Administration. [http://www.osha.gov/SLTC/samplinganalysis/index.html]. Date accessed: 

January 2012.

SKC [2007]. SKC UMEX 100 passive badge: publication 1529. [http://www.skcinc.com/

instructions/1529.pdf]. Date accessed: January 2012.
Health Hazard Evaluation Report 2008-0099-3152 Page 35

Appendix B: Tables and Figures

Table B1. Air sampling results for metalworking fluids, June 9–10, 2009

Sample Type Location Sample 

volume (liters)

Sample time 

(minutes)

Concentration mg/m3

Total thoracic 

particulate 

mass*

Extracted 

MWF

Personal breathing zone

Front end 1006 679 0.17 ND†

Front end 1045 657 0.28 (0.19)‡

Front end 956 601 (0.10) ND

Front end 1022 647 0.19 (0.07)

Front end 989 622 0.19 (0.08)

Front end 1005 636 0.19 (0.12)

Front end 1048 663 0.13 ND

Front end 1006 649 0.17 ND

Front end 1049 664 (0.090) ND

Front end 986 632 0.13 ND

Front end 1030 644 0.22 (0.14)

Front end 1029 651 0.12 ND

Printer 938 590 0.13 ND

Printer 1000 641 0.11 ND

Printer 997 638 0.27 0.21

Printer 1008 638 (0.090) ND

Necker 906 596 (0.070) ND

General area Front end 901 574 0.28 0.19

NIOSH REL-TWA 0.40

MDC§ 0.03 0.06

MQC¶ 0.098 0.18

*The NIOSH REL-TWA for MWF aerosols of 0.4 mg/m3 of air is based on the total thoracic particulates and not the 

extractable fraction of MWF. The total thoracic particulates include all dust and other aerosols in the air in addition to the 

MWFs that fall within that size range. The extractable fraction represents the portion of the sample that was MWFs.

†ND = not detected (below the minimum detectable concentration).

‡Concentrations between the MDC and MQC are shown in parentheses to point out that there is more uncertainty 

associated with these values than with concentrations above the MQC.

§The MDC was calculated by dividing the method limit of detection by the average sample volume collected (1.0 cubic meter).

¶The MQC was calculated by dividing the method limit of quantitation by the average sample volume collected (1.0 cubic meter).
Page 36 Health Hazard Evaluation Report 2008-0099-3152

Appendix B: Tables and Figures (continued)

Table B2. Air sampling results for inorganic acids, June 9–10, 2009

Sample type Job title/location

Sample 

volume 

(liters)

Sample 

time

(minutes)

Concentration (mg/m3)

Hydrofluoric

acid Sulfuric acid

Personal breathing 

Zone

Chemical process 

operator 99.8 504 (0.0096)* ND†

General area

HF acid tank 111 567 (0.007) ND

HF acid tank 86 426 0.24 (0.04)

Can washer 85 420 (0.010) (0.042)

Can washer 114 572 (0.006) (0.027)

Sulfuric acid tank 83 425 (0.005) ND

NIOSH REL-TWA 2.5 1

NIOSH REL-Ceiling 5

OSHA PEL-TWA 2.5 1

MDC‡ 0.001 0.03

MQC§ 0.011 0.10

*Concentrations between the MDC and MQC are shown in parentheses to point out that there is more 

uncertainty associated with these values than with concentrations above the MQC.

†ND = not detected (below the minimum detectable concentration).

‡The MDC was calculated by dividing the method limit of detection by the average sample volume collected 

(0.096 cubic meter).

§The MQC was calculated by dividing the method limit of quantitation by the average sample volume collected 

(0.96 cubic meter).
Health Hazard Evaluation Report 2008-0099-3152 Page 37

Appendix B: Tables and Figures (continued)

Table B3. Air sampling results for formaldehyde, June 9–10, 2009

Sample type Job title/Location Sample time 

(minutes)

Sample 

volume* (liters)

Concentration 

(ppm)

Personal breathing zone

Front end 635 18.2 0.023

Front end 618 17.7 0.040

Front end 673 19.3 0.039

Front end 650 18.6 0.048

Front end 662 18.9 0.035

Front end 650 18.6 0.066

Front end 655 18.7 0.048

Front end 666 19.1 0.047

Front end 630 18.0 0.039

Front end 636 18.2 0.058

Front end 658 18.8 0.038

Printer 612 17.5 0.090

Printer 640 18.3 0.080

Printer 640 18.3 0.071

Printer 546 15.6 0.13

Printer 625 17.9 0.12

Chemical process operator 505 14.4 0.020

Chemical process operator 650 18.6 0.031

Millwright 602 17.2 0.040

Forklift operator 651 18.8 0.080

Lacquer spray 640 18.3 0.042

General area

Conference room 702 20.1 0.040

Outdoor 703 20.1 0.0056)†

Outdoor 667 19.1 (0.011)

NIOSH REL-TWA 0.016

NIOSH REL-Ceiling (15 minute sample) 0.1

OSHA PEL-TWA 0.75

ACGIH TLV-Ceiling 0.3

MDC‡ 0.005

MQC§ 0.016

*Because passive diffusion sampling badges were used, the volume of air sampled was calculated, in liters, using 

the following formula: time (min) X sampling rate (28.6 mL/min) ÷ 1000.

†Concentrations between the MDC and MQC are shown in parentheses to point out that there is more uncertainty 

associated with these values than with concentrations above the MQC.

‡The MDC was calculated by dividing the limit of detection by the average sample volume collected (18.3 liters).

§The MQC was calculated by dividing the limit of quantitation by the average sample volume collected (18.3 liters).

Concentration 

(ppm)
Page 38 Health Hazard Evaluation Report 2008-0099-3152

Appendix B: Tables and Figures (continued)

Table B4. Air sampling results for 2-dibutylaminoethanol, June 9–10, 2009

Sample Type Job Title/Location Sample Time 

(minutes)

Sample Volume 

(liters)

Concentration 

(mg/m3)

Personal breathing zone

Printer 552 28 0.26

Printer 613 30 0.25

Printer 507 25 0.20

Printer 643 32 0.24

Printer 595 29 0.24

Printer 640 32 0.21

General Area

Printer 579 29 0.28

Printer 584 29 (0.11)*

NIOSH REL-TWA 14

OSHA PEL-TWA None

ACGIH TLV-Ceiling 3.5

MDC† 0.03

MQC‡ 0.13

*Concentrations between the MDC and MQC are shown in parentheses to point out that there is more 

uncertainty associated with these values than with concentrations above the MQC.

†The MDC was calculated by dividing the method limit of detection by the average sample volume collected (29 

liters).

‡The MQC was calculated by dividing the method limit of quantitation by the average sample volume collected 

(29 liters).
Health Hazard Evaluation Report 2008-0099-3152 Page 39

Appendix B: Tables and Figures (continued)

Table B5. Air sampling results for endotoxin, June 9–10, 2009

Sample type Job Title/Location Sample Time 

(minutes)

Sample Volume 

(liters)

Endotoxin units per 

cubic meter of air

Personal breathing zone

Front end 635 18.2 0.023

Front end 618 17.7 0.040

Front end 673 19.3 0.039

Front end 650 18.6 0.048

Front end 662 18.9 0.035

Front end 650 18.6 0.066

Front end 655 18.7 0.048

Front end 666 19.1 0.047

Front end 630 18.0 0.039

Front end 636 18.2 0.058

Front end 658 18.8 0.038

Printer 612 17.5 0.09

Printer 640 18.3 0.080

Printer 640 18.3 0.071

Printer 546 15.6 0.13

Printer 625 17.9 0.12

General area Outdoors 1.1

NIOSH REL-TWA None
Page 40 Health Hazard Evaluation Report 2008-0099-3152

Appendix B: Tables and Figures (continued)

Table B6. Personal noise dosimetry results, June 9–10, 2009

Job title Start time Stop time Minutes

OSHA 

action 

level 

(dBA)

OSHA 

PEL 

(dBA)

NIOSH 

REL 

(dBA)

Back end operator (lacquer spray) 7:50 18:30 640 97.5 97.4 98.8

Back end operator (lacquer spray) 8:05 18:05 600 99.0 98.9 100.5

Back end operator (necker) 8:25 18:25 600 99.9 99.9 102.2

Back end operator (necker) 8:02 18:05 603 99.9 99.8 102.7

Baler room/forklift 7:20 18:43 683 94.9 94.6 95.6

Baler room/forklift 7:55 18:49 654 95.6 95.4 97.0

Front end ironer trimmer 7:18 18:20 662 93.4 92.9 95.4

Front end ironer trimmer 7:15 18:10 655 93.8 93.4 95.7

Front end ironer trimmer 7:25 18:15 650 96.5 96.4 97.8

Front end ironer trimmer/chemical process operator 7:39 15:30 471 91.3 90.6 93.4

Front end ironer trimmer leadman 7:43 18:10 627 95.0 94.8 96.5

Front end ironer trimmer leadman 7:20 18:26 666 95.2 95.0 96.5

Front end ironer trimmer line 3 7:29 18:42 673 97.7 97.6 99.0

Front end ironer trimmer lines 1 and 2 7:22 18:15 653 96.2 95.8 97.9

Front end maintenance/repair* 7:25 18:05 640 88.6 86.3 91.0

Material handler 8:16 15:29 433 81.3 71.2 84.2

Material handler 7:45 18:33 648 87.3 81.8 89.8

Millwright* 8:15 18:20 605 87.7 84.3 90.7

Millwright* 7:43 18:30 647 89.8 87.4 93.4

Palletizer 8:08 18:10 602 85.6 72.5 86.6

Palletizer 7:45 18:36 651 86.9 77.3 88.0

Printer 7:55 18:05 610 98.2 98.2 99.7

Printer 7:45 18:10 625 98.6 98.5 100.1

Printer 7:35 18:15 640 98.8 98.8 100.3

Printer 7:50 17:01 555 100.2 100.0 101.2

Printer leadman 7:30 18:10 640 98.9 98.8 100.4

Noise exposure limits

12-hour work shift 82.1 90.0 83.4

*8-hour work shift 85.0 90.0 85.0
Health Hazard Evaluation Report 2008-0099-3152 Page 41 

Appendix B: Tables and Figures (continued)

Figure B1. Octave band analysis for cupper band press.

Figure B2. Octave band analysis for ironers.
Page 42 Health Hazard Evaluation Report 2008-0099-3152

Appendix B: Tables and Figures (continued)

Figure B3. Octave band analysis for printers.

Figure B4. Octave band analysis for necker machines.
Health Hazard Evaluation Report 2008-0099-3152 Page 43

Appendix B: Tables and Figures (continued)

Figure B5. Octave band analysis for lacquer spray machines.

Figure B6. Octave band analysis for baler.
Page 44 Health Hazard Evaluation Report 2008-0099-3152

Appendix C: Occupational Exposure Limits and Health Effects

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 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 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 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. 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 2008-0099-3152 Page 45

Appendix C: Occupational Exposure Limits and Health Effects

 (continued)

(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 assessment 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 for the compounds we measured, as well as a 

discussion of the potential health effects from exposure to these compounds.

Metalworking Fluids

MWFs are complex mixtures used to cool, lubricate, and remove metal chips from tools and metal parts 

during machining of metal stock. The term MWF aerosol refers to the mist generated during machining. 

This mist may contain a variety of substances including any component of the MWF, additives to the 

MWF, contaminants of the MWF such as oils, metals, corrosion inhibitors, and biological contaminants.

Exposure to MWFs can result from inhalation of aerosols or from skin contact due to touching 

contaminated surfaces, handling of parts and equipment, splashing of fluids and settling of MWF aerosol 

on the skin [NIOSH 1998a]. Inhalation of MWF aerosols may cause irritation of the throat (e.g., sore, 

burning throat), nose (e.g., runny nose, congestion, and nosebleeds), and lungs (e.g., cough, wheezing, 

increased phlegm production, and shortness of breath). MWF aerosol exposure has been associated 

with chronic bronchitis, asthma, hypersensitivity pneumonitis, and worsening of pre-existing respiratory 

problems. Skin contact with MWFs may cause allergic contact dermatitis and/or irritant contact 

dermatitis depending on the chemical composition of the fluid, types of additives and contaminants 

contained in the MWFs, type of metal being machined (e.g., nickel or chromium), and the exposed 
Page 46 Health Hazard Evaluation Report 2008-0099-3152

Appendix C: Occupational Exposure Limits and Health Effects

 (continued)

individual’s tendency for developing allergies. Petroleum-based products, certain chemical additives, and 

strong detergents and hand cleansers may also cause dermatitis or aggravate an existing condition.

Synthetic, semisynthetic, and soluble oil MWFs like the ones used at this company are diluted with water 

and hence can be a breeding ground for bacteria if an inadequate amount of biocide is added. High 

temperature and low pH, and the presence of metals can also favor bacterial growth. Levels of microbial 

contamination indicate the cleanliness or degree of maintenance of the MWF. Inhalation of MWF 

aerosols containing bacteria may result in respiratory problems. Employees with broken skin may develop 

skin infections if they have contact with MWF contaminated with bacteria.

At this time, there is insufficient health data for NIOSH to recommend a specific limit for bacterial or 

fungal contamination in MWF. However, some researchers have suggested that well-maintained MWFs 

should have bacterial concentrations below 106 CFU/mL of fluid [Rossmoore and Rossmoore 1994]. 

On the Web site “Management of the Metal Removal Fluid Environment.” the Organization Resources 

Counselors, Inc. recommends maintaining bacterial levels < 105 CFU/mL and fungal levels 

< 100 CFU/mL [http://www.aware-services.com/orc].

NIOSH recommends that exposures to MWF aerosols be limited to 0.4 mg/m3

 for the thoracic particulate 

mass, as a TWA concentration for up to 10 hours per day during a 40-hour workweek [NIOSH 1998a]. 

The NIOSH REL is intended to prevent or greatly reduce respiratory disorders associated with MWF 

exposure. In addition, limiting dermal (skin) exposure is critical to preventing allergic and irritant 

disorders related to MWF exposure. NIOSH recommends that all employees exposed to MWFs at over 

half the REL receive medical monitoring, and all employees with exposure to MWF may benefit from 

medical monitoring [NIOSH 1998a]. Supervision of the medical monitoring program should be done by 

a physician or other health professional with expertise in the identification and management of MWFrelated respiratory conditions and skin diseases. Employees should be encouraged to continue to report all 

potential work-related skin problems to the plant medical department.

Formaldehyde

The most commonly reported and best documented health complaints due to exposure to low 

concentrations of formaldehyde include irritation of the eyes, nose, and throat; nasal congestion; 

headaches; skin rash; and asthma. NIOSH recognized formaldehyde as a potential occupational carcinogen 

in 1981 and, following the NIOSH carcinogen policy in existence at the time, set the REL to the “lowest 

feasible concentration,” which for formaldehyde was defined as the analytical limit of quantification of 

0.016 ppm for up to a 10-hour time-weighted average and a ceiling limit of 0.10 ppm that should not be 

exceeded [NIOSH 1981, 2010]. Since then, experience has shown that this REL is actually not the “lowest 

feasible concentration” because formaldehyde in the ambient air can exceed 0.016 ppm, a fact later 

acknowledged by NIOSH [Lemen 1987]. Additionally, the subsequent revision of the NIOSH carcinogen 

policy [NIOSH 1995], combined with better exposure characterization and advances in risk assessment and 

management strategies, support the need for NIOSH to reassess the formaldehyde REL that is in progress.
Health Hazard Evaluation Report 2008-0099-3152 Page 47

Appendix C: Occupational Exposure Limits and Health Effects

 (continued)

Noise

Noise-induced hearing loss is an irreversible, sensorineural condition that progresses with exposure. 

Although hearing ability declines with age (presbycusis), noise exposure produces more hearing loss than 

that resulting from aging alone. This NIHLis caused by damage to nerve cells of the inner ear (cochlea) 

and, unlike some conductive hearing disorders, cannot be treated medically [Berger et al. 2003]. In most 

cases, NIHL develops slowly and usually occurs before it is noticed. Hearing loss is often severe enough to 

permanently affect a person’s ability to hear and understand speech. For example, people with hearing loss 

may not be able to distinguish words such as “fish” from “fist” [Suter 1978].

The dBA is the preferred unit for measuring sound levels to assess employee noise exposures. The dBA 

noise scale is weighted to approximate the sensory response of human ears to sound frequencies near 

the hearing threshold. Because the dBA scale is logarithmic, increases of 3 dBA, 10 dBA, and 20 dBA 

represent a doubling, tenfold increase, and hundredfold increase of sound energy, respectively. Noise 

exposures expressed in dBA cannot be averaged by taking the arithmetic mean.

The OSHA noise standard [29 CFR 1910.95] specifies a PEL of 90 dBA, as an 8-hour TWA. The OSHA 

PEL is calculated using a 5 dB exchange rate. This means that a person may be exposed to noise levels of 

95 dBA for no more than 4 hours, 100 dBA for 2 hours, 105 dBA for 1 hour, etc. An employee’s daily 

noise dose, based on the duration and intensity of noise exposure, can be calculated according to the 

formula

 Dose = 100 X (C1/T1 + C2/T2 + ... + Cn/Tn ),

where Cn indicates the total time of exposure at a specific noise level and Tn indicates the reference 

duration for that level as given in Table G-16a of the OSHA noise regulation. Doses greater than 100% are 

in excess of the OSHA PEL.

When noise exposures exceed the PEL of 90 dBA, OSHA requires that employees wear hearing protection, 

and that an employer implement feasible engineering or administrative controls to reduce noise exposures. 

The OSHA noise standard also requires an employer to implement a hearing conservation program 

when 8-hour TWA noise exposures exceed the AL 85 dBA. The program must include noise monitoring, 

employee notification, observation, audiometric testing, hearing protectors, training, and record keeping.

NIOSH [NIOSH 1998b] and ACGIH [ACGIH 2011] recommend an exposure limit of 85 dBA, as an 

8-hour TWA. A more conservative 3 dB exchange rate is used in calculating exposure these limits. Using 

NIOSH criteria, an employee can be exposed to 85 dBA for 8 hours, but to no more than 88 dBA for 4 

hours, 91 dBA for 2 hours, 94 dBA for 1 hour, etc. Twelve-hour exposures have to be 83.2 dBA or less 

according to the NIOSH REL.

Audiometric evaluations of employees hearing thresholds must be conducted in quiet locations, preferably 

in a sound-attenuating booth, by presenting pure tones of varying frequencies at threshold levels (i.e., the 

level of a sound that the person can just barely hear). Zero dB hearing loss represents the hearing level of 
Page 48 Health Hazard Evaluation Report 2008-0099-3152

an average, young individual with good hearing. OSHA requires hearing thresholds to be measured at test 

frequencies of 500, 1,000, 2,000, 3,000, 4,000, and 6,000 Hz. Individual employee’s annual audiograms 

are compared to their baseline audiogram to determine if an STS has occurred. OSHA states that an STS 

has occurred if the average threshold values at 2,000, 3,000, and 4,000 Hz have increased by 10 dB or 

more in either ear when comparing the annual audiogram to the baseline audiogram [29 CFR 1910.95]. 

The NIOSH-recommended hearing threshold shift criterion is a 15-dB shift at any frequency in either ear 

from 500–6,000 Hz measured twice in succession [NIOSH 1998b]. Both of these hearing threshold shift 

criteria require at least two audiometric tests.

The audiogram profile is a plot of the hearing test frequencies (x-axis) versus the hearing threshold levels 

(y-axis). For many employees, the audiogram profile tends to slope downward toward the high frequencies 

with an improvement at the audiogram’s highest frequencies, forming a notch [Suter 2002]. A notch in 

the audiogram of an employee with otherwise normal hearing may indicate the early onset of hearing loss. 

The notch from occupational noise usually occurs at frequencies from 3,000 Hz to 6,000 Hz [ACOM 

1989; Osguthorpe and Klein 2001]. However, it is generally accepted that a notch at 4,000 Hz indicates 

occupational hearing loss [Prince et al. 1997]. An individual may have notches at different frequencies in 

one or both ears [Suter 2002]. For this evaluation, a notch is defined as the frequency where the hearing 

level is preceded by an improvement of at least 10 dB and followed by an improvement of at least 5 dB.

Contact Dermatitis

Contact dermatitis makes up 90% to 95% of all occupational skin diseases [Ingber and Merims 2004; 

Lushniak 2004]. Contact dermatitis, both irritant and allergic, is an inflammatory skin condition caused 

by skin contact with agents such as chemical irritants (irritant contact dermatitis) or allergens (allergic 

contact dermatitis). Exposed areas of the skin, such as hands and forearms, have the greatest contact with 

irritants or allergens and are most commonly affected. In fact, more than 80% of occupational contact 

dermatitis involves the hands [Warshaw et al. 2003; Belsito 2005; Flyvholm et al. 2007]. More than 57,000 

chemicals are reported to cause skin irritation, but only 3,700 chemicals are known skin allergens [Belsito 

2005]. Usually only a small percentage of people are susceptible to skin allergens.

The cause of irritant contact dermatitis is often due to many factors. The most common skin irritant is 

wet work, defined as exposure of skin to liquid for more than 2 hours per day, use of occlusive gloves for 

more than 2 hours per day, or frequent hand washing [Chew and Maibach 2003; Slodownik et al. 2008]. 

Other common causes of irritant contact dermatitis include soaps and detergents, solvents, food products, 

cleaning agents, plastics and resins, petroleum products and lubricants, metals, and machine oils and 

coolants [Chew and Maibach 2003; Slodownik et al. 2008].

The first steps in dermatitis prevention are to avoid irritants, allergens, and wet work. Liberal use of skin 

moisturizers helps to prevent contact dermatitis by maintaining a healthy skin barrier, and also helps to 

repair this barrier if it has been compromised [Chew and Maibach 2003]. Proper handwashing methods, 

such as using lukewarm or cool water and mild cleansers, are also valuable in preventing contact dermatitis 

[Warshaw 2003].

Appendix C: Occupational Exposure Limits and Health Effects

 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 49

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 (continued)
Health Hazard Evaluation Report 2008-0099-3152 Page 51

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 (OSHA) Act of 1970, 29 U.S.C. 669(a)(6) which 

authorizes the Secretary of Health and Human Services, following 

a written request from any employer or authorized representative 

of employees, to determine whether any substance normally found 

in the place of employment has potentially toxic effects in such 

concentrations as used or found. HETAB also provides, upon 

request, technical and consultative assistance to federal, state, and 

local agencies; labor; industry; and other groups or individuals to 

control occupational health hazards and to prevent related trauma 

and disease.

Mention of 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 Manuel Rodriguez, Christine 

West, and Scott E. Brueck of HETAB, Division of Surveillance, 

Hazard Evaluations and Field Studies. Industrial hygiene field 

assistance was provided by James Couch. Industrial hygiene 

equipment and logistical support was provided by Donald Booher 

and Karl Feldmann. Medical field assistance was provided by 

Carlos Aristeguieta. Analytical support was provided by Bureau 

Veritas North America. Statistical support was provided by 

Charles Mueller. 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 plant, the state health department, and the 

OSHA 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 (NTIS) at 5825 Port 

Royal Road, Springfield, Virginia 22161.
Below is a recommended citation for this report:

NIOSH [2012]. Health hazard evaluation report: air contamininant, noise, and 

dermal hazards during aluminum beverage can manufacturing – Texas. By 

Rodriguez M, West C, Brueck SE. 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. 2008-0099-3152.

To receive NIOSH documents or information about 

occupational safety and health topics, contact NIOSH at:

1-800-CDC-INFO (1-800-232-4636)

TTY: 1-888-232-6348

E-mail: cdcinfo@cdc.gov

or visit the NIOSH web site at: www.cdc.gov/niosh.

For a monthly update on news at NIOSH, subscribe to 

NIOSH eNews by visiting www.cdc.gov/niosh/eNews.

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