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DHHS (NIOSH) Publication No. 2009–135 

May 2009 

SAFER • HEALTHIER • PEOPLETM

i
Software Disclaimer of Liability Clause 

The Determination of Sound Exposures (DOSES) software was developed by the National Institute for 

Occupational Safety and Health (NIOSH). It is provided “as is” without warranty of any kind, including express 

or implied warranties of merchantability or fitness for a particular purpose. By acceptance and use of this 

software, which is conveyed to the user without consideration by NIOSH, the user expressly waives any and all 

claims for damage and/or suits for personal injury or property damage resulting from any direct, indirect, 

incidental, special or consequential damages, or damages for loss of profits, revenue, data or property use, 

incurred by the user or any third party, whether in an action in contract or tort, arising from access to, or use of, 

this software in whole or in part. 

No further development or upgrades for this software are planned. Any questions concerning this product can 

be directed to the NIOSH Pittsburgh Research Laboratory, Hearing Loss Prevention Branch (412-386-6560). 

System Requirements 

To run the DOSES program effectively, your computer should meet the following system requirements: 

Operating system Windows 2000/XP/Vista 

Hardware Minimum Recommended 

Processor Pentium 200 MHz or equivalent Pentium III or greater or Celeron 

600 MHz or equivalent 

Disk space 80 MB 80 MB 

Memory 64 MB of RAM 256 MB of RAM 

Screen resolution 800 × 600 1024 × 768 

ii
Determination of Sound Exposures (DOSES): 

Software Manual and Implementation Guide 

By Gregory P. Cole, Ellsworth R. Spencer, and Eric R. Bauer, Ph.D. 

CONTENTS 

Page 

INTRODUCTION............................................................................................................................................ 1 

 

COLLECTING TIME-MOTION DATA............................................................................................................... 2 

 Task Observations Versus Location Observations ............................................................................. 2 

 Timeframe Recorded............................................................................................................................ 2 

 Duration ................................................................................................................................................ 2 

 Data Sheets ......................................................................................................................................... 3 

 Instrumentation .................................................................................................................................... 4 

 

INTERPRETATION OF RESULTS................................................................................................................... 4 

 Interventions......................................................................................................................................... 5 

 Intervention Examples.......................................................................................................................... 5 

 Intervention Success............................................................................................................................ 5 

 

USER INSTRUCTIONS..................................................................................................................................... 6 

1. Start DOSES (Splash Screen) ......................................................................................................... 6 

2. OPEN Time Study .................................................................................................................... 6 

3. Time Study Properties - New Study Screen ................................................................................... 7 

4. Time Study Editor .................................................................................................................... 10 

5. Time Study Analysis .................................................................................................................... 15 

6. Frequently Asked Questions........................................................................................................... 18 

 

REFERENCES ............................................................................................................................................... 21 

 

APPENDIX.—MSHA Equipment and Occupation Codes ............................................................................. 22 

 

ILLUSTRATIONS 

1. Example of Time-Motion Study Sheet ............................................................................................ 3 

 

TABLES 

1. Dosimeter Settings.......................................................................................................................... 4 

iii
iv

ACRONYMS AND ABBREVIATIONS USED IN THIS REPORT 

AL action level 

DOSES Determination of Sound Exposures 

MSHA Mine Safety and Health Administration 

NEC not elsewhere classified 

NIOSH National Institute for Occupational Safety and Health 

PEL permissible exposure level 

REL recommended exposure limit 

SL sound level 

SLM sound level meter 

UNIT OF MEASURE ABBREVIATIONS USED IN THIS REPORT 

dB decibel 

dB(A) decibel, A-weighted 

hr hour 

m meter 

MB megabyte 

MHz megahertz
INTRODUCTION 

The Determination of Sound Exposures (DOSES) software was developed by the National Institute for 

Occupational Safety and Health (NIOSH) specifically for use by mine management and safety personnel. 

DOSES simplifies the record-keeping and analysis associated with time-motion studies and worker noise 

exposures, making it easier to identify and solve noise problems. 

The software relies on a time-motion study that profiles the worker’s daily activities. At the same time, noise 

measurements are collected with a dosimeter or sound level meter (SLM). Observations about the worker’s 

location and tasks or other activities are recorded along with times and durations so they can later be matched 

up with the noise data. 

After the completion of a time-motion study of the worker’s daily tasks and locations (possible noise sources), 

which measures the worker’s noise exposures during the recorded events, the information is entered into 

DOSES. The program then displays information about the worker’s accumulated noise dose over time. 

When the sound level (SL) is constant over the entire work shift, the daily worker’s noise dose (D), in percent, 

is given by: 

D = 100 C/T 

where C = the total length of the workday, in hours, 

and T = the reference duration corresponding to the measured SL. 

When the daily noise exposure consists of periods of different noise levels, the daily dose (D) is calculated 

according to the following formula: 

D = 100 × (C1/T1 + C2/T2 + ... + Cn/Tn) 

where Cn = total time of exposure at a specified noise level, 

and Tn = exposure time at which noise for this level becomes hazardous. 

The software gives the user the option of assessing dose relative to the NIOSH recommended exposure limit 

(REL), the Mine Safety and Health Administration (MSHA) permissible exposure level (PEL), or the MSHA action 

level (AL). To obtain the NIOSH REL dose the software uses a 3-dB exchange rate, an 80-dB threshold level, 

and an 85-dB criteria level [NIOSH 1998]. To obtain the MSHA PEL dose the software uses a 5-dB exchange 

rate, a 90-dB threshold level, and a 90-dB criteria level. To obtain the MSHA AL dose the software uses a 5-dB 

exchange rate, an 80-dB threshold level, and a 90-dB criteria level [64 Fed. Reg.1 49548 (1999)]. 

1Federal Register. See Fed. Reg. in references. 

 The 

software uses the following formulas to calculate dose: 

 NIOSH REL dose = 0 for dB(A) < 80 

 = (Duration / (8 /(2 (Leq − 85)/3))) * 100 

 MSHA PEL dose = 0 for dB(A) < 90 

 = (Duration / (8 / (2 (Leq − 90)/5))) * 100 

 MSHA AL dose = 0 for dB(A) < 80 

 = (Duration / (8 / (2 (Leq − 90)/5))) * 100 

where duration is in units of hours and Leq is the SL taken from the SLM or dosimeter data. 

 

1
The software generates a variety of interactive on-screen displays showing where, when, and how the worker’s 

noise dose accumulated. It also can generate customizable printed reports. These outputs can be used to 

highlight the tasks, locations, and times that are associated with the greatest amount of the worker’s noise 

exposure. Mine safety personnel can then use these reports to make decisions about how to reduce or 

eliminate the factors that are creating an overexposure. 

 

COLLECTING TIME-MOTION DATA 

 

As with any computer program, the utility and outcome of DOSES depends greatly on the quality of information 

entered. Task observation, or time-motion study, is the basis for the program’s input and must be complete 

and detailed. Gaps in observations and recorded durations will produce poor results, comparisons, and 

misguided and ineffective exposure reduction attempts. For effective time-motion studies, the following must 

be considered: task observations or location observations, timeframe recorded, and full- or partial-shift 

observations. 

Task Observations versus Location Observations 

Depending on the classification of the worker being observed, it may be better to use one method of 

observation over another. Most of the time it is recommended and logical to use task observations. This is 

when the duration of each task that the worker performs is recorded. Observing a machine operator, for 

instance, would logically involve task observations because these operators tend to remain with the machine, 

positioned at a relatively fixed location, and perform a uniform and repeated series of tasks throughout their 

shift. For example, a continuous miner operator, even operating remotely, would stay at a relatively fixed 

position with respect to the continuous miner and complete tasks such as tramming, cutting, loading, cutting 

and loading, waiting on shuttle car, etc. 

Location observations best suit time studies of workers who move about frequently during the shift, perform 

many different tasks, and spend time at many locations. Examples include utility workers in underground coal 

mines or plant workers at coal preparation plants. These workers are on the move during the entire shift but 

return to specific locations often during the shift. They may repeat similar tasks, but tend to repeat them at the 

same locations throughout the shift. 

It is recommended that no matter which method of observation is used, detailed notes should be taken. When 

task observations are employed, the specific location of those tasks should be noted on the data sheets. 

Conversely, when location observations are used, the specific tasks being performed at each location must be 

noted. The end goal is to be able to get an accurate picture of each component of the employee’s noise 

exposure so that crucial noise exposures can be managed and the difference in total dose (baseline versus 

control) can be ascertained. 

Timeframe Recorded 

A second important part of the data collection process is determining the timeframe for recording each 

task/location. At a minimum, times should be recorded to the minute. Even better is to note the time intervals 

to the second, i.e., in the format hr:min:sec. As experience is gained conducting observations for various 

occupations, the precision and detail of both the observations and recording times will be easier to determine 

based on length of each task or time at each location. Long-duration tasks/locations likely require a less 

stringent time recording (hr:min), while rapidly occurring tasks or changing locations would require a “tighter” 

recording time (hr:min:sec). 

Duration 

The duration of the observations must be considered. Full-shift observations take just that—a full shift—

to complete, plus the time needed to enter the observation data and dosimeter files into DOSES. This is a 

substantial time commitment for the industrial hygienist or safety person. It can be difficult to free up an entire 

shift to complete the observations, but it is recommended that full-shift observations be done. Not only does 

2
this result in a complete description of what the worker does during a shift, it also gives the full-shift dose for 

compliance purposes. 

For certain workers, partial-shift observation can still be useful when time does not permit full-shift 

observation. If a worker is known to perform the same tasks, the same number of times, and for the same 

duration each time during a shift, it may be possible to ascertain that worker’s exposures with a partial-shift 

observation. Observing several complete cycles of each of the tasks performed may be sufficient. 

Data Sheets 

The abbreviated data collection sheet shown in Figure 1 is an example of the type of information that should 

be recorded when completing a time-motion study for use in the DOSES program. The bold items are standard 

to the sheet, while the nonbold items would be filled in by the observer. DOSES is designed for time-motion 

study data to be entered by start/stop time. The start and stop time of each work task and/or location and the 

related SL measurement are critical to the final analysis report. It is important to keep the start and stop times 

sequential without any gaps. DOSES uses the total time of a task or location to determine its contribution to 

the worker’s daily dose. Leaving gaps between the time periods or entering the time period without a task or 

location will reduce the effectiveness of the DOSES program. It is also important to attempt to list all possible 

tasks or locations on the data sheets before beginning the study and to leave some blank columns for 

unanticipated tasks or locations. The program also requires entries for the date of the study, the employee’s 

MSHA occupation code, and the MSHA equipment operated code (see appendix for full code lists). These data 

are needed to complete the DOSES analysis of the worker’s work tasks and/or location contributions to the 

cumulative daily dose and for the mine’s noise control database. 

Data Sheet Observations for: Continuous Miner Operator

Date: 11/11/2007 Mine: XYZ Section: North 11 Emp. First Name: Sam 

Unique ID: 1234 Manufacturer: Smith Model: XYZ-1 Serial No.: 12345 

Normal Shift: [Y] Shift Production: 2,000 tons Dosimeter Tag: 12345 

Observer: Jane Doe Other Info: Pittsburgh Coal Seam 3.4 m 

Task - Location Observations 

Time Start Time Stop Mantrip Downtime Con. Miner 

Operator Face 

Tramming 

Crosscut 

Sound Level 

Measurements 

06:00:00 06:25:20 X 95 dB(A) 

06:25:20 07:00:45 X 73 dB(A) 

07:00:45 11:00:00 X 97 dB(A) 

- - - - - - - - - - - - - - - - - - - - - - - - - - - - 

15:05:05 15:20:05 X 92 dB(A) 

15:20:05 15:55:10 X 75 dB(A) 

15:55:10 16:20:45 X 97 dB(A) 

Figure 1.—Example of Time-Motion Study Sheet. 

3
When using the time-motion study sheet, there is a need to be consistent, especially within a specific job 

classification. First, it is important to always label the worker occupations with the same names using the 

MSHA occupation codes (see appendix). Secondly, it is suggested that the exact same task names or location 

names be used. This allows for comparisons between time studies of the same employee and between 

employees with the same occupations. 

Instrumentation 

The instrumentation best suited for conducting exposure and SL analyses includes a person-wearable 

dosimeter for monitoring worker noise exposure and an SLM for measuring the SLs for each task or at each 

work location. The brand of dosimeter is not important. DOSES allows for downloading of dosimetry data from 

all of the dosimeters commonly used at mining operations because they have received MSHA intrinsic safety 

approval for use in underground coal mines. Most unlisted dosimeters can also be used as long as they 

provide time-stamped sound pressure level data in plain ASCII text files. Therefore, companies can choose 

their own SLM or dosimeter for measuring SLs. 

Dosimeter settings for the NIOSH REL, MSHA PEL, and MSHA AL are shown in Table 1. For most mining 

applications, the MSHA PEL and AL are the dosimeter settings likely to be used, although DOSES does not 

require any particular setting as long as a time and sound pressure level are being saved to the dosimeter’s 

internal memory. DOSES calculates the dose relative to three criteria—NIOSH REL, MSHA PEL, and AL—from the 

time and SLs downloaded from the dosimeter. 

Table 1.—Dosimeter Settings 

Designation 

NIOSH REL 

Parameters Settings 

Weighting A 

Threshold level 80 dB 

Exchange rate 3 dB 

Criterion level 85 dB 

MSHA PEL 

Response Slow 

Upper limit 140 dB 

Weighting A 

Threshold level 90 dB 

Exchange rate 5 dB 

Criterion level 90 dB 

MSHA AL 

Response Slow 

Upper limit 140 dB 

Weighting A 

Threshold level 80 dB 

Exchange rate 5 dB 

Criterion level 90 dB 

 

Response Slow 

Upper limit 130 dB 

INTERPRETATION OF RESULTS 

The primary outcome of DOSES is an understanding of a worker’s noise exposure, what causes that exposure, 

or locations where the exposure is occurring. The charts, graphs, and tables generated by DOSES are all 

designed to display this important information. Specifically, the outputs summarize a worker’s tasks/locations, 

time at each task/location, and dose accumulated at each task/location. This information is initially displayed 

as a compilation by tasks/locations, listed from highest accumulated dose task/location to lowest 

accumulated dose task/location. This information can be sorted by task/location, duration, or accumulated 

dose. Mine safety personnel should be looking for the tasks or locations that result in the most accumulated 

dose. Once this determination has been made, then the appropriate intervention strategies can be selected. 

4
5

Interventions directed at the tasks or locations that result in the most dose have the best chance of 

significantly reducing a worker’s noise exposure. 

Interventions 

Interventions fall into one of two types: engineering controls or administrative controls. Engineering noise 

controls attempt to reduce the SLs at the source or along the path from the source to receiver. The worker is 

exposed for the same length of time, but since the SL is reduced, less noise exposure occurs. Engineering 

controls might include quieter motors, reduced impact noise, barriers, sound-absorbing material, control 

rooms, and reduced metal-to-metal contact. Administrative controls attempt to remove the worker from the 

noisy area. In this case, the SLs remain the same, but since the worker does not spend as much time near the 

noise, the overall noise exposure is reduced. Administrative controls may include minimizing or eliminating 

tasks in high SL areas, remote monitoring, training to allow for faster task completion, and job rotation. In most 

cases, the most effective noise reduction is the use of an engineering control that reduces the SL. When all 

feasible engineering controls are implemented, administrative noise controls are the next best choice. One 

starting point for identifying specific engineering and administrative controls is MSHA Program Information 

Bulletin No. P08–12, “Technologically Achievable, Administratively Achievable, and Promising Noise Controls 

(30 CFR Part 62)” [Stricklin et al. 2008]. 

Intervention Examples 

One of the workers in underground coal mining likely to experience noise overexposures is the continuous 

mining machine operator. Exposure data collected by NIOSH showed that continuous mining machine 

operators had MSHA PEL doses as high as 347% [Bauer et al. 2006]. Some of the interventions that have 

been implemented include coated flight bars and coated tail rollers (engineering controls) and remote operator 

positioning and job rotation (administrative controls). 

In another case, plant operators in coal preparation plants had MSHA PEL doses as high as 221% [Bauer et al. 

2006]. The plant operators are the workers that routinely travel throughout the plant checking processes, 

cleaning, and performing minor maintenance. They are exposed to many different SLs emanating from any 

number of different pieces of processing equipment. Some of the interventions include: urethane screen 

decking, chute liners, and enclosing noise sources such as air compressors and pumps (engineering controls); 

control booths, remote monitoring, restricting travel to lowest SL areas, and job rotation with control room 

operators (administrative controls). Finally, in surface coal mining, dragline oilers had MSHA PEL measured 

doses as high as 193% [Bauer et al. 2006]. Interventions have included: sound barrier curtains around motorgenerator sets, quieter motor blower fans, and wrapping of ductwork with insulation (engineering controls); 

restricting oiler time in the “house,” remote greasing, and job rotation with dragline operator and dozer 

operator (administrative controls). 

Intervention Success 

Judging intervention success is accomplished by conducting a time study after a noise control has been 

implemented, then comparing the postintervention time study with the preintervention time study. For 

inst7ance, if an engineering control has been implemented, one would look to see if the accumulated dose has 

been reduced for the task that is completed where the equipment has had the engineering control applied. If 

an administrative control has been employed as the exposure reduction method, one would simply check to 

see if the time spent at that location or task is less and, subsequently, if the result is less dose accumulation. 

DOSES allows these types of analyses to be completed rather easily by comparing pre- and postintervention 

tables or dose graphs. 
USER INSTRUCTIONS 

1. Start DOSES (Splash Screen) 

When the DOSES program is opened it displays the Start DOSES splash screen that shows three button 

choices: OPEN Time Study, NEW Time Study, and Continue. 

To open a saved file, select the OPEN Time Study button. A file browse dialog is displayed to allow selection of 

a previously saved study (go to 2). 

To enter a new study, select the NEW Time Study button. A properties dialog is displayed for defining a new 

study (go to 3). 

To close this screen, select the Continue button, the Start DOSES screen closes, and the DOSES Time Study 

Editor screen is displayed in a disabled mode. From here select Open, New or Exit from the File menu, or the 

Help files can be viewed. The other menus will be disabled until an existing study is opened or a new study is 

created. 

 

Start DOSES Screen 

When the DOSES program is selected, 

the program opens and displays a Start 

DOSES splash screen that shows three 

button choices: OPEN Time Study, NEW 

Time Study, and Continue. Clicking in 

the dialog box “Do not show this dialog 

in the future” will prevent this screen 

from coming up when DOSES is opened 

again. 

 

 

2. OPEN Time Study 

After selecting OPEN Time Study, the 

Select Study to Open dialog opens. 

A saved study can be opened by clicking 

on the study file and clicking the OK

button or double-clicking on the study 

file (go to 4). 

 

6
3. Time Study Properties - New Study Screen: Time Study Tab 

After selecting NEW Time Study, the 

Time Study Properties - New Study

screen opens on the first time study 

property tab: Time Study. This window 

is the default screen when NEW Time 

Study is selected from the Start DOSES

screen. The other tabs—Employee, 

Mine, Shift, and Dosimeter—contain 

additional information to complete 

about the time study. After all of the 

desired information is entered, clicking 

the OK button moves the user to the 

DOSES Time Study Editor screen to 

enter the time-motion data. 

When the Time Study Properties - New 

Study screen is opened, the current 

date is automatically inserted by the 

program and shown on the screen 

for viewing and documentation 

purposes. The Creation Date cannot 

be changed by the user. 

The name of the person doing the 

study is entered under the Recording Person window. 

The date of the study is entered under the Date of Time Study window. This can be done manually typing in the 

date or by clicking on the calendar icon to the right of the dialog box and selecting the date. 

Notes or comments that were taken during the actual time-motion study can be added now or later in the text 

box under Time Study Notes. 

7
Time Study Properties - New Study Screen: Employee

The next time study property tab to be 

selected and filled out is Employee. The 

Employee property contains five 

parameters: Employee Name, 

Employee ID, Work Location/Section, 

Occupation, and Equipment Operated. 

The employee name and ID being 

studied are entered under the Employee 

Name and Employee ID text box, 

respectively. 

As part of the time-motion study, the 

work location is 

recorded in the Work Location/Section

text box. 

The employee’s official MSHA 

occupation/title and equipment 

operated code is selected from the 

Occupation list box and the 

Equipment Operated list box by clicking 

on the appropriate line. 

A Code Quick Find text boxes located within the Employee property are available to quickly set the Occupation

and Equipment Operated codes. The Code Quick Find text box for the Occupation is only available when 

entering a new study. The Occupation code cannot be changed once the properties dialog has been closed 

when creating a new time study. 

 

Time Study Properties - New Study Screen: Mine Tab. 

The Mine property contains three 

parameters: Company Name, Mine 

Name, and Mine MSHA ID Number. The 

information can be entered into the text 

boxes immediately or at a later time. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

8
Time Study Properties - New Study Screen: Shift 

The Shift property contains four 

parameters: Shift Start, Shift Length, 

Shift Tonnage (Raw), and Shift Tonnage 

(Clean). 

 

 

Time Study Properties - New Study Screen: Dosimeter Tab 

 

If a dosimeter was not used, click OK at 

the bottom of the screen (go to 4). 

The Dosimeter property tab specifies 

the dosimeter characteristics. These 

include the Dosimeter Manufacturer, 

Model, Serial #, Log File information, 

and Calibration and Exposure Details. 

To make changes, select the desired 

parameter and make the change using 

the keyboard or mouse. 

Enter the dosimeter Manufacturer, 

Model and Serial # in the test boxes 

under Dosimeter. 

Enter the dosimeter’s pre- and postcalibrations, dose results and run time 

information in the appropriate text 

boxes under Calibration and Exposure 

Details. 

NOTE: The calibration information 

is used for record keeping only, 

and is not factored in to the program calculations. 

If a log file was extracted from the dosimeter for comparison use in the DOSES program, complete the 

information under Log File. Pay close attention to specifying the format of the ASCII file exported from the 

dosimeter or the data may not import in to DOSES correctly. 

9
NOTE: The dosimeter log file information is not needed to complete the analysis. 

If changes were made mistakenly, press the Cancel button. When the Cancel button is pressed a confirmation 

dialog opens with Yes or No options. If Yes is chosen, the properties dialog is closed without saving the 

changes and control returns to the DOSES Time Study Editor screen. If No is chosen, then the Time Study 

property remains open for editing. 

Set Study Start Time Dialog 

 

After the NEW Time Study properties are defined, a 

Set Study Start Time dialog appears and prompts 

for the Start Time to be set. After the Start Time is 

set the DOSES Time Study Editor screen enables 

and sets the observation parameters to their 

default values. The first observation Stop Time can 

now be set by either entering the duration or the 

stop time of the observation. Whichever method is 

chosen, the other field will automatically update to 

reflect the same time. The Task Name, Task 

Location, and SL (sound level) are then entered. 

The Dose is automatically calculated and displayed 

in % as the SL is entered. 

 

 

 

4. Time Study Editor 

The Time Study Editor screen is initially 

disabled when the program starts. 

However, this screen is enabled when an 

existing Time Study is opened or a New 

Time Study is successfully started. This 

screen contains these three areas: 

Observation Editor, Table View, and Graph 

View. At the top of the screen, four menus 

are available: File, Observation, Analysis, 

and Help. 

10
Time Study Editor: File Menu 

The File menu contains the following options: 

Option Description 

New: Creates a new time study. This will 

automatically bring up the Time Study 

Properties dialog. 

Open: Opens an existing time study using the 

File Browse dialog. 

Save: Saves the current time study. 

Save As: Saves the current time study under a 

different name. A File Save dialog is 

opened, which permits the name of 

the file to be changed. 

Properties: Activates the Time Study Properties 

dialog to allow the user to view or 

modify the properties of the current 

time study. 

Exit: Exits the DOSES program. 

 

Time Study Editor: Observation Menu 

 

The Observation menu contains the following options: 

Option Description 

Previous: Moves to the previous observation 

in the list. 

Next: Moves to the next observation in 

the list. If already at the last 

observation, this option will create 

a new observation entry and add it 

to the end of the list. 

Move to Last: Moves directly to the last 

observation in the list. 

Add: Adds a new observation to the end 

of the list. 

Delete Last N: Deletes a number (N) of 

observations from the list using 

the Delete Last N dialog. 

Time Study Editor: Analysis Menu 

The Analysis menu contains the following options: 

Option Description 

Dose 

Calculation: 

Provides an expanded list to 

choose the active dose calculation. 

The options are: 

NIOSH REL Uses an 85-dB(A) criterion level 

with a 3-dB tradeoff. 

MSHA PEL Uses a 90-dB(A) criterion level with 

a 5-dB tradeoff. 

MSHA AL Uses a 90-dB(A) criterion level with 

a 5-dB tradeoff. 

Analyze Data Activates the Time Study Analysis

dialog. 

11
NOTE: The active dose calculation can be changed at any time. 

 

Time Study Editor: Help Menu 

The Help menu contains the following options: 

Option Description 

Do Not Show 

Splash Screen: 

Toggles On/Off the option to 

show the Start DOSES Screen on 

program start. 

Help Topics: Displays the online help. 

Disclaimer: Displays the NIOSH Disclaimer 

dialog. 

About: Displays the About DOSES dialog. 

Observation Editor Area 

This area is initially disabled when the 

program starts. The screen is enabled

when an existing Time Study is opened 

or a New Time Study is successfully 

started. 

The Observation Editor contains five 

main areas: 

1. Previous/Next Observation 

2. Start/Stop Time & Duration 

3. Task Name & Task Location 

4. SL & Dose 

5. Editing Buttons 

Previous/Next Observation 

Pressing the up or down yellow arrows allow for movement backward and forward in the list of observations. 

Start/Stop Time & Duration Text Boxes 

 

Each observation is defined in terms of a Start Time and Stop Time. The Start Time is set once, when 

initializing the first observation with the Set Study Start Time dialog. From then on, the observation Start Time

is automatically set based on the Stop Time of the previous observation. The Stop Time is set as part of 

defining a new observation. It can be set by entering the exact stop time or by entering the Duration in hours, 

minutes, and seconds. Regardless of how the Stop Time is set, the other stop time fields will update 

automatically. 

NOTE: Only the Stop Time of the last observation can be changed. If the Stop Time of an observation 

within the study needs to be changed, all observations following must be deleted and reentered. This 

is to ensure time continuity in the observations. 

Task Name & Task Location List Boxes 

The task name and task location are entered for each observation. Entry is made by selecting the list box dropdown arrow and choosing from the list. 

A short explanation is displayed inside the list box for quick assistance. When starting a NEW Time Study with a 

previously unused occupation code, the “Add/Edit...” option is the only option available for both Task Name

and Task Location. After selecting Yes to the Do you want to Edit Task List? dialog, an Edit Item List dialog 

12
appears, allowing for items to be added or removed from the list. Once the Add/Edit is completed, the new 

item(s) can be selected throughout the time study. The Task Name and Task Location list boxes are initially 

empty when creating a study using a new employee occupation code. They are populated as the observations 

are entered and automatically saved for future use according to the employee occupation code. 

 

NOTE: Removing an item from the list box does not remove it from the observations in the time study. 

Those entries will have to be manually reset to a valid list box value. 

Sound Level and Dose

 

Sound level (SL) is a way of measuring the sound pressure (and perceived loudness of sounds) on a 

logarithmic scale, usually in dB units. However, in this case, dB(A) is used to measure the sound. This 

represents the A-weighting of the SL. 

Each observation contains an SL dB(A) number that is entered by either typing the number in the area provided 

or by using the numeric up/down control and moving to the desired number. The numeric up/down control 

increases or decreases the number by 1 dB(A). 

Dose represents the % of noise exposure based on the duration and SL of the observation. It is calculated 

based on one of three formulas chosen from the Analysis menu: 

NIOSH REL dose = 0 for dB(A) < 80 

 = (Duration / (8 / (2 (Leq − 85)/3))) * 100 

 MSHA PEL dose = 0 for dB(A) < 90 

= (Duration / (8 / (2 (Leq − 90)/5))) * 100 

 MSHA AL dose = 0 for dB(A) < 80 

 = (Duration / (8 / (2 (Leq − 90)/5))) * 100 

where duration is in units of hours and Leq is the SL taken from a sound level meter or dosimeter data. 

NOTE: The dose is calculated by the program from the SL and duration of the exposure. 

Editing Buttons

There are three Editing Buttons: Add, Delete Last N, and Move to Last. They are located on the top right of the 

DOSES Time Study Editor screen. 

The Add button automatically adds a new observation to the end of the list with the Start Time set to the Stop 

Time of the previous observation and the duration set to 1 minute. It is then possible to continue to set Stop 

Time, Task Name, Task Location, and SL for that observation. 

The Delete Last N button, when pressed, brings up the Delete Last N Observations dialog where the number of 

observations to be deleted (from the end of the study) is specified. This number can be entered by typing in the 

preferred number or by clicking on the numeric up/down control. 

The Move to Last button sets the current observation to the last one entered into the time study. 

13
 

 

 

 

Table View 

The Time Study Table View is located in 

the center of the DOSES Time Study 

Editor screen. The Table View provides 

a tabular view of the observations that 

were entered into the time study. 

Movement around the Table View is 

possible. The table is updated automatically as observation data are entered. New data cannot be entered by 

clicking on the last row of the table. The current observation will have a blue border around it. 

 

 

 

 

Graph View 

The Time Study Graph View is located at 

the bottom of the DOSES Time Study 

Editor screen. The graph provides a plot of 

the observed SL and cumulative dose over 

the duration of the time study. The graph 

is updated automatically as observation 

data are entered. 

The graph crosshair will be centered on 

the Stop Time of the current observation 

and anchored to the cumulative dose plot. 

NOTE: Positioning the mouse cursor over the blue vertical or horizontal line of the crosshair and holding 

the left button down on the mouse will allow the user to move the crosshair to access the graph. In the 

Time Study Table the row chosen by the graph crosshair will have a blue border around it. 

After all the data are entered, the Analysis menu can be selected. From the Analysis drop-down menu, leftclicking on Analyze Data will activate the Time Study Analysis dialog. 

Time Study Analysis Dialog 

The Analysis dialog contains six tabs: Summary, Raw Data, Study vs. Dosimeter, Exposure Comparison, Study 

vs. Study, and Printing & Export. Selecting Analyze Data from the Analysis menu on the DOSES Time Study 

Editor screen permits access to this dialog. The Summary tab is displayed by default when DOSES Time Study 

Analysis opens. The file name is displayed in the title bar of the dialog for reference. 

14
5. Time Study Analysis Dialog – Summary Tab 

 

In the Summary section, the analyzed 

data are shown in two separate tables—

one where the breakdown is by Task, 

the other where the breakdown is by 

Location. Included for reference beside 

the Breakdown By Task table is the 

Overall Noise Exposure (%) generated 

from the time study. 

The Breakdown by Task table has a row 

for each unique Task Name in the time 

study. Columns associated with each 

row include the # Obs., Total Time, 

% Dose, and LAVG dB(A). 

 

 

 

 

# Obs.: The total number of observations where the same task was performed during the 

time study. 

Total Time: The total time where the same task was performed during the time study. 

% Dose: The total dose received by the subject during a specific task during the time study. 

LAVG dB(A): The average of the A-weighted SLs where the same task was performed during the 

time study. 

The table can be sorted by clicking on any of the column headers. Clicking the same column header multiple 

times will toggle the sort between ascending and descending order. 

It is possible to visually chart the information contained in the table by clicking the Draw Chart button located 

below the table. The adjacent list box provides the option to chart the # Obs., Total Time, % Dose, or LAVG dB(A)

versus the Task Name. To change the category, select from the list box by using the drop-down arrow. 

Time Study Analysis Dialog – Raw Data Tab 

The Raw Data section is a tabular view 

of the time study data. It is a larger 

version of the Table View found on the 

DOSES Time Study Editor screen. In the 

Raw Data section, the table can be 

sorted by clicking on any of the column 

headers. Clicking the same column 

header multiple times will toggle the 

sort between ascending and descending 

order. 

 

 

15
 

 

 

 

Time Study Analysis Dialog – Study vs. Dosimeter 

The Study vs. Dosimeter tab is where 

the cumulative Dose from both the time 

study and dosimeter are plotted for 

comparison. The dosimeter data comes 

from the Dosimeter Log File specified in 

the Dosimeter property. Ideally, the two 

plots should be close to one another. 

NOTE: If no Dosimeter Log File is 

specified, only the time study plot 

will be shown. 

 

 

 

 

 

 

 

 

 

 

 

 

Time Study Analysis Dialog – Exposure Comparison

The Exposure Comparison tab displays 

a plot of the three different calculations 

(NIOSH REL, MSHA PEL, and MSHA AL) 

using the time study data. The purpose 

is to provide a comparative view of the 

three methods using the same data. 

 

 

 

 

 

 

 

 

 

 

16
Time Study Analysis Dialog – Study vs. Study 

The Study vs. Study tab enables a 

comparison of the current time study 

with another. The comparison is on the 

Breakdown by Task. Selection of 

Study 2 is done by clicking on the yellow 

folder in the middle of the screen. The 

tables can be sorted in ascending or 

descending order by clicking on the 

column headings. The Overall Noise 

Exposure section is shown for both 

studies. 

 

 

 

 

Time Study Analysis Dialog – Printing & Export 

The Printing & Export tab has the 

controls for printing reports and 

exporting the data. 

 

Printing a Report 

There are two report options for 

printing: Study Report and Study vs. 

Study. Specific options can be chosen 

for what parts to include in the study 

report by clicking the appropriate 

checkboxes. 

After the report option is chosen, leftclick the Print button to access the print 

dialog. From this dialog, select 

whether to print to a file (HTML) 

or selected printer and the page 

orientation. 

 

Exporting Time Study Data 

There are three options for which data to export: 

• Breakdown by Task results from the Summary tab 

• Breakdown by Location results from the Summary tab 

• Raw data as seen in the table on the Raw Data tab 

The data are exported in an ASCII comma-delimited format with a default .csv extension which makes it 

readable by Microsoft Excel. After selecting the export option, left-click the Export button to access the export 

file dialog to select or choose to destination file. 

 

17
6. Frequently Asked Questions 

 

What is DOSES? 

DOSES stands for Determination of Sound Exposures. It is a program designed to analyze tasks and 

locations of task sound exposures associated with them. Based on these data, the program can calculate 

worker sound exposure during a miners’ work shift. 

What happens when DOSES is opened for the first time? 

 

When DOSES opens for the first time, a display Start DOSES splash screen appears. If OPEN Time Study is 

selected, a file browse dialog is displayed to allow for selection of a previously saved study. When NEW Time 

Study is selected, a properties dialog is displayed for defining a new study. When opened, the Time Study 

property is displayed first. If Cancel is selected, the Start Doses screen closes and the DOSES Time Study 

Editor screen is displayed in disabled mode. 

Can the original display screen be opened again? 

No, the original display screen or splash screen is opened only when the DOSES icon is selected from the 

desktop. However, if a new Time Study is desired, open the File menu and select New. 

Why is the Date of Time Study grayed out? 

When the Date of the Time Study is grayed out, it indicates that the user is not in a NEW Time Study. Once 

the Date of the Time Study has been entered, it is grayed out on the screen to indicate that it cannot be 

changed. 

Is it possible to cancel out of the properties after a New Study is selected? 

Yes, it is possible to cancel out of the Time Study properties at any time. DOSES will then open to the 

previous screen. 

What notes are entered in the Time Study? 

 

Any notes that are taken throughout the Time Study are recorded here. 

 

Can the Start Time be edited? 

The Start Time cannot be edited; it is set only once after the New Time Study properties have been 

determined. From then on, the observation Start Time is automatically set based on the Stop Time of the 

previous observation. 

Can the Stop Time be edited? 

Yes, the Stop time can be edited. After the initial Start Time is set, a Stop Time or duration must be entered 

for each task. However, since the Start Time is determined by subsequent tasks, only the Stop Time of the 

last observation can be changed. If the Stop Time of an observation within the study needs to be changed, 

all of the subsequent observations must be deleted and reentered. 

Why are some of the boxes on the DOSES Time Study Editor screen grayed out?

When a NEW Time Study is active and information is being entered, there are five areas that can be added 

or changed: Stop Time or duration, Task Name, Task Location, and SL. The Start Time and Dose are grayed 

out, but remain visible for viewing purposes. However, if viewing a previously saved time study, only the 

18
Task Name, Task Location, and SL can be edited. Therefore, the other boxes are grayed out, indicating that 

changes cannot be made. 

Can a previously saved Time Study be opened? 

Yes, a previously saved Time Study can be opened. Time Studies are saved in a file with a .tstudy extension. 

What is Code Quick Find? 

Code Quick Find is a text box located in the Employee property within the Occupation and the Equipment 

Operated area. Typing in the number quickly displays the desired area of selection. 

Why is the Occupation Code Quick Find text box grayed out? 

When the Code Quick Find area is grayed out, it indicates that the mandatory Occupation selection was 

made and therefore cannot be changed. 

Can previously saved Task Names or Task Locations be reused? 

Yes, once any Task Name or Task Location is entered, it is available to be used again within the same 

study. 

What do the letters “SL” refer to? 

“SL” stands for sound level. A sound pressure level taken from an SLM or dosimeter that has been 

processed through the instrument’s A-weighting filter is referred to as a “sound level” (SL). 

What is TWA? 

TWA stands for time-weighted average. The 8-hr time-weighted average sound level, dB(A), can be 

calculated from the daily dose (D) according to the following formula: TWA (8) = 10 × Log (D/100) + 85 for 

the NIOSH REL. The formula for the MSHA REL is: TWA (8) = 16.61 × Log10 (D/100) + 90. The TWA (8) 

dB(A) is used so that all work shifts regardless of length can be easily compared. 

What does dB(A) refer to? 

 

dB(A) refers to decibels measured with A-weighting. dB(A) is a commonly used frequency weighting that 

closely approximates the frequency response of the human ear. The human ear does not perceive sounds 

of equal sound pressure level as being equally loud if the frequencies are different. The ear is less sensitive 

at low frequencies. 

A-weighting is commonly used to measure environmental and industrial noise when assessing potential 

hearing damage and other noise effects at moderate- to high-intensity levels. 

Before printing a chart, can the color be changed? 

Yes, the color can be changed by selecting the Draw Bar Chart located on the DOSES Time Study Analysis 

screen. Click on the colored text box labeled Bar color and select the desired color for the chart. This is 

located in the upper right corner of the DOSES Chart Breakdown Data dialog. 

Why does the Observation # begin at 0? 

 

The initial Start Time is set and is defined as observation number 0. Therefore, each observation begins 

at 0, representing the first entry. 

19
What are the yellow up/down arrows used for? 

After the NEW Time Study properties are defined, a Set Study Start Time dialog appears and prompts for 

the Start Time to be set. After the Start Time is set, the yellow up/down arrows are used to enter all 

subsequent observations. 

NOTE: The first Observation # always begins at 0. 

What does the Delete Last N button do? 

The Delete Last N button, located on the Observation Editor screen when selected, will bring up the Delete 

Last N Observations dialog where the number of observations to delete is set. Upon confirmation, the 

observations are deleted. 

NOTE: Observations can only be deleted from the end of the time study due to the time dependence of the 

start and stop times. 

20
21

REFERENCES 

64 Fed. Reg. 49548 [1999]. Mine Safety and Health Administration: health standards for occupational noise 

exposure; final rule (30 CFR Parts 56, 57, 62, 70, and 71). 

Bauer ER, Babich DR, Vipperman JS [2006]. Equipment noise and worker exposure in the coal mining industry. 

Pittsburgh, PA: 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. 2007–105, IC 9492. 

MSHA [2001]. Information resource center. Part 50: diskette user’s handbook. Available at: 

http://www.cdc.gov/niosh/mining/data/pdfs/codes.pdf

NIOSH [1998]. 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 

Stricklin KG, Quintana FA, Skiles ME [2008]. Technologically achievable, administratively achievable, and 

promising noise controls (30 CFR part 62). Arlington, VA: Mine Safety and Health Administration, Program 

Information Bulletin No. P08–12, June 18, 2008. Available at: http://www.msha.gov/regs/complian/PIB/

2008/pib08-12.pdf
APPENDIX.—MSHA EQUIPMENT AND OCCUPATION CODES 

MSHA Equipment Codes [MSHA 2001] 

Code Equipment 

00 Generic equipment 

01 Aerial tram 

02 Air compressor 

03 Air transportation 

04 Auger machine (coal) (surface and 

underground) 

05 Large shop-powered tools 

06 Blow pipe/gun (air blasting) 

07 Boats, barges 

08 Bulldozer 

09 Carriage-mounted drills 

10 Chute 

11 Classifier, cyclones 

12 Continuous miner, tunnel borer 

13 Conveyor 

14 Crane, derrick 

15 Crusher, breaker, ball and rod mills 

16 Cutting machine 

17 Dimension stone cutting/polishing machinery 

18 Dredge 

19 Elevator, skip, cage 

20 Electric/hydraulic coal drills 

21 Fan 

22 Flotation and filters 

23 Forklift 

24 Front-end loader 

25 Gathering arm loader 

26 Grizzlies 

27 Gunite, shotcrete machine 

28 Handtools (not powered) 

29 Handtools (powered) 

30 Hoist car, dropper 

31 Hydraulic jets (monitors) 

32 Impactor (pneumatic) 

33 Load-haul-dump, scoop, bobcat 

34 Locomotive 

35 Longwall machine (plow, shearer, shield, 

stageloader) 

36 Longwall subparts (jacks, chocks) 

37 Mantrip, jeep 

38 Man lift (not elevator) 

39 Mill grinding 

40 Milling machine 

22

Code Equipment 

41 Mine car (supply) 

42 Mine car (ore, coal) 

43 Mucking machine 

44 Ore haulage trucks (off highway, 

underground) 

45 Ore haulage trucks (highway) 

46 Packaging machine 

47 Pneumatic blasting agent loader 

48 Pump 

49 Raise borer 

50 Raise climber 

51 Raw coal storage 

52 Road grader 

53 Rock drill (jackleg) 

54 Roof bolting machine 

55 Rock dusting machine 

56 Rotary dump 

57 Scraper, pan 

58 Screen 

59 Shortwall machine 

60 Shovel (stripping, dragline, bucket-wheel) 

61 Shuttle car 

62 Skip pocket 

63 Slusher, scraper, scram 

64 Tamping machine, railroad 

65 Track maintenance and repair 

66 Tractor (underground) 

67 Trucks, all other 

68 Tugger air winch 

69 Washers 

70 Welding machine 

71 Machine, NEC 

 
MSHA Occupation Codes [MSHA 2001] 

Code Occupation 

000 Generic occupation 

001 Belt/Conveyor Man 

002 Electrician 

003 Electrician Helper 

004 Mechanic/Repairman 

005 Mechanic Helper 

006 Rock Duster 

007 Blaster/Shooter/Shotfirer 

008 Stopping Builder/Ventilation Man/Mason 

009 Supplyman 

010 Timberman/Jacksetter/Propman 

011 Wireman 

015 Fan Attendant 

016 Laborer 

019 Cement Man 

024 Trainee 

025 Bobcat Operator 

026 Grizzly Man/Car Dump Opr 

028 Scoop Tram-Load Haul Opr 

029 Mucking Machine Opr 

030 Slusher Operator 

031 Shotfirer Helper 

032 Brattice Man 

033 Coal Drill Helper 

034 Coal Drill Operator 

035 Continuous Miner Helper 

036 Continuous Miner Operator 

037 Cutting Machine Helper 

038 Cutting Machine Operator 

039 Hand Loader 

040 Headgate Operator 

041 Jack Setter (Longwall) 

042 Loading Machine Helper 

043 Loading Machine Operator 

044 Longwall Shearer Operator 

045 Rockman 

046 Roof Bolter/Rock Bolter 

047 Roof Bolter Helper 

048 Roof Bolter Mounted 

049 Section Foreman 

050 Shuttle Car Operator 

051 Stall Driver 

052 Tailgate Operator 

053 Utility Man 

054 Scoop Car Operator 

Code Occupation 

057 Stope Miner 

058 Drift Miner 

059 Raise Miner 

063 Miner, NEC 

064 Contract Miner 

067 Power Shovel Operator 

068 Bulldozer Operator 

070 Auger Operator 

071 Auger Helper 

072 Mobile Bridge Operator 

074 Tractor Operator/Motorman 

075 Grader operator/Roadgrader operator 

076 Truck Driver 

078 Crane Opr./Dragline/Backhoe 

082 Frontend Loader Operator 

101 Belt/Conveyor Man 

102 Electrician 

103 Electrician Helper 

104 Mechanic/Repairman 

105 Mechanic Helper 

106 Rock Duster 

108 Stopping Builder/Ventilation Man/Mason 

109 Supplyman 

110 Timberman/Propman/Jacksetter 

111 Wireman 

112 Belt Vulcanizer 

113 Cleanup Man 

114 Coal-MN Sampler 

115 Fan Attendant 

116 Laborer 

117 Rodman 

118 Oiler/Greaser 

119 Welder 

122 Coal Dump Operator 

123 Transit Man 

124 Trainee 

126 Grizzly Man/Car Dump Opr 

128 Load Haul Dump Opr/Gizmo 

149 Bullgang Foreman/Labor Foreman 

154 Belt Cleaner 

155 Chainman 

156 Rock Driller 

157 Pumper 

158 Rock Machine Operator 

159 Water Line Man 

23
160 Shopman/Machinist 

163 Miner NEC 

167 Power Shovel Operator 

168 Bulldozer Operator 

175 Grader Operator 

176 Truck Driver 

178 Crane Opr/Dragline/Backhoe 

182 Frontend Loader Operator 

201 Belt/Conveyor Man 

216 Trackman 

220 Cager 

221 Hoistman/Engineer 

224 Transportation Trainee 

230 Skip Tender 

240 Loader Head/Roscoe Operator 

255 Chainman 

261 Battery Station Operator 

262 Brakeman/Roperider/Snapper 

263 Track Foreman 

265 Dispatcher 

269 Motorman/Swamper/Switchman 

276 Driver/Tractor Opr/Jeep 

277 Buggy Pusher 

301 Conveyor Operator 

302 Electrician 

303 Electrician Helper 

304 Mechanic/Repairman 

305 Mechanic Helper 

306 Welder (Non-Shop) 

307 Blaster/Shooter/Shotfirer 

308 Mason 

309 Supplyman/Supply Truck 

Driver/Warehouseman 

310 Scraper Operator 

311 Wireman 

312 Belt Vulcanizer 

313 Cleanup Man 

314 Coal Sampler 

315 Fan Attendant 

316 Laborer/Utility Man/Pumper 

317 Rodman 

318 Oiler/Greaser 

319 Welder (Shop) 

320 Cage Attendant/Cager 

321 Hoistman/Engineer 

322 Dump Operator 

323 Transit Man 

324 Trainee 

325 Bobcat Operator 

326 Forklift Operator 

327 Surface Miner 

328 Utility Man 

329 Vacuum Filter Operator 

330 Skip Tender 

331 Clam/Claw Operator 

333 Drill Helper 

334 Drill Operator 

340 Boom Operator 

341 Belt Man/Conveyor Man 

342 Bit Sharpener 

343 Car Trimmer/Car Loader 

344 Car Shake-Out Operator 

345 Crusher Attendant 

347 Froth Cell Operator 

348 Machinist 

349 Rotary Dump Operator 

350 Shuttle Car Operator 

351 Scoop Operator 

352 Steel Worker 

354 Sweeper Operator 

355 Chainman 

356 Rock Driller 

357 Washer Operator 

358 Water Circuit Operator 

359 A Self-Propelled Compactor Operator 

360 Machinist 

362 Brakeman/Trip Rider 

363 Miner NEC/Quarry Worker 

365 Dispatcher 

366 Waterboy 

367 Power Shovel Operator 

368 Bulldozer Operator 

369 Motorman/Locomotive Operator 

370 Auger Operator 

371 Auger Helper 

372 Barge Attendant/Boat/Dredge 

373 Car Dropper 

374 Cleaning Plant Operator 

375 Road Grader Operator 

376 Truck Driver 

378 Washer Operator 

379 Dryer Operator 

380 Fine Coal Plant Operator 

381 Hoist Operator Helper 

382 High Lift Operator/Front End Loader 

383 Highwall Drill Helper 

384 Highwall Drill Operator 

385 Lampman 

24
25

386 Refuse Truck Driver/Backfill Truck Driver 

387 Rotary Bucket Excavator Operator 

388 Scalper-Screen Operator 

389 Forklift Operator 

390 Silo Operator 

391 Stripping Shovel Operator 

392 Tipple Operator 

393 Weighman 

394 Carpenter 

395 Water Truck Operator 

396 Watchman/Guard 

397 Yard-Engine Operator 

398 Dimnsn Stone Cutter/Polisher 

402 Master Electrician 

404 Master Mechanic 

414 Dust Sampler/Lab Technician 

418 Maintenance Foreman 

423 Surveyor 

430 Assistant Mine Foreman/Asst Mine Mngr 

449 Mine Foreman/Mine Manager 

456 Engineer (Electricity/Ventilation/Mining) 

462 Fire Boss Pre-Shift Examiner 

464 Inspector 

481 Superintendent 

489 Outside Foreman 

494 Preparation Plant Foreman Safety Director 

495 Safety Director 

496 Union Representative 

497 Outside Foreman 

590 Education Specialist 

591 Mineral Industrial Safety Officer 

592 Mine Safety Inspector 

593 Safety Representative 

594 Training Specialist 

999 Unknown or NEC
Delivering on the Nation’s promise:

Safety and health at work for all people

through research and prevention

To receive NIOSH documents or more 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

DHHS (NIOSH) Publication No. 2009-135

May 2009