No. 536 July 2009 

NIOSH Develops New Software to Analyze and Reduce 

Hazardous Noise Exposure

Objective 

To help mine safety and health professionals 

manage and reduce hazardous noise exposure with a 

software tool that simplifies the record-keeping and 

analysis process. 

Background 

Hearing loss resulting from overexposure to 

noise continues to be a problem throughout the U.S. 

mining industry. Studies indicate that 70%–90% of 

all miners have a noise-induced hearing loss severe 

enough to be classified as a hearing disability by the 

time they reach retirement age. To address this 

problem, the National Institute for Occupational 

Safety and Health (NIOSH) developed the Determination of Sound Exposures (DOSES) software 

program. DOSES is designed specifically for 

use by mine management and safety personnel to 

simplify the record-keeping and analysis associated 

with time-motion studies, making it easier to 

identify and solve noise exposure problems. 

Approach 

DOSES relies on time-motion study data that 

profile a worker’s daily activities. In this case, that 

information is the task and location breakdown of a 

worker’s regular working routine. In addition, as 

task and location data are noted, associated sound 

levels are collected using a dosimeter or sound level 

meter. The data are then entered into the program 

(Figure 1) as complete observations made of the 

following parameters: 

• Start time 

• Stop time 

• Task name 

• Task location 

• Sound level 

With the time-motion and sound level data 

entered into the program, analysis is moved from 

the clipboard to the computer where extensive 

analysis of the worker’s noise exposure over time 

can be conducted. 

 Figure 1.—The DOSES Time Study Editor with areas for entering new or editing existing observations, a table displaying the 

observations, and a graphical plot of cumulative dose and sound 

level versus time. 
Results

DOSES assesses noise exposure by analyzing the 

time-motion study data of a worker’s daily schedule 

broken down by task and location. This analysis is 

shown visually on the main screen in tabular form 

and as a plot of the cumulative dose and observed 

sound level over time as each observation from the 

time study is entered. As each entry is completed, 

the percent noise exposure is calculated using one 

of three formulas chosen by the user (Table 1). 

Table 1.—Formulas used to calculate percent dose 

 Designation Percent dose formula 

NIOSH REL = 0 for Leq < 80 

=   100

2

8

3)85( 



 





Duration Leq

MSHA PEL = 0 for Leq < 90 

=   100

2

8

5)90( 



 





Duration Leq

MSHA AL = 0 for Leq < 80 

=   100

2

8

5)90( 



 





Duration Leq

REL Recommended exposure limit. 

PEL Permissible exposure level.

AL Action level. 

Duration Exposure time, in hours. 

Leq Equivalent sound level. 

Once the study is completely entered, a more indepth analysis is performed where cumulative exposures by task and location are calculated and 

displayed in tables (Figure 2) and bar graphs (Figure 3). If a dosimeter was used during the time 

study, the dosimeter log file can be imported into 

the program for comparison to the observationbased results. 

 Figure 2.—The first tab in the Analysis dialog showing the 

breakdown by task and location tables.

Figure 3.—Bar chart of percent dose versus task. 

Customizable reports from the data can be generated and printed or saved in HTML format. With 

these analysis capabilities, high noise exposure aspects of the job can be easily identified by task or 

location, allowing the safety officer to mitigate 

them with engineering or administrative noise controls. The raw time study observation data can also 

be exported in comma-separated ASCII format for 

easy use by other programs. 

For More Information 

The DOSES software program can be downloaded from the NIOSH Mining Web site at: http://

www.cdc.gov/niosh/mining/products/

For more information about the DOSES program, contact Gregory P. Cole (412-386-6744, 

GPCole@cdc.gov), Ellsworth R. Spencer (412-386-

6831, ESpencer@cdc.gov), or the Pittsburgh Health 

Communications Coordinator (pithealth@cdc.gov), 

NIOSH Pittsburgh Research Laboratory, P.O. Box 

18070, Pittsburgh, PA 15236-0070. 

To receive NIOSH documents or for more information 

about occupational safety and health topics, contact: 

1-800-CDC-INFO (1-800-232-4636), 1-888-232-6348 

(TTY), e-mail: cdcinfo@cdc.gov, or visit the NIOSH 

Web site at http://www.cdc.gov/niosh

Mention of any company name or product does not 

constitute endorsement by the National Institute for 

Occupational Safety and Health.

DHHS (NIOSH) Publication No. 2009–150