Direct Reading and Sensor Technologies

Miner using the NIOSH developed personal dust monitor.


Direct-reading methods and sensors are being used more frequently in many different settings ranging from personal monitoring of individual health to applications in research and in clinical practice. NIOSH began organized research in this area in 2008 with the creation of the DREAM initiative (Direct Reading Exposure Assessment Methods). NIOSH will build upon and expand the DREAM program to address lessons learned, advances in technology, and stakeholder contributions. NIOSH researchers have developed a number of direct-reading methods and monitors and are exploring new ways to use these technologies to improve occupational safety and health.

The use of sensors has increased exponentially as countless remote wireless sensors are now employed for monitoring the environment, work sites, disaster response, “smart” buildings and facilities, and in agriculture and health. Wireless data transfer based on cell phone networks and smart phone technology is enhancing the adoption of these sensors, and allowing integration of geographically disperse sensors to produce comprehensive exposure pictures. Wearable and even implantable sensors are being developed that could aid in exposure assessment and clinical practice.

NIOSH Center for Direct Reading and Sensor Technologies

The NIOSH Center for Direct Reading and Sensor Technologies (NCDRST) was established in May 2014 to coordinate research and to develop recommendations on the use of 21st century technologies in occupational safety and health. The NCDRST is a virtual center hosted by the NIOSH Division of Applied Research and Technology and the NIOSH Exposure Assessment Cross Sector Program.

NCDRST Objectives

  1. Coordinate a national research agenda for direct-reading methods and sensor technologies. Research on these technologies has been incorporated into the goals of the NIOSH Strategic Plan for fiscal years 2019-2023.
  2. Develop guidance documents pertinent to direct-reading methods and sensors, including validation and performance characteristics;
  3. Develop training protocols; and
  4. Establish partnerships to collaborate in the Center’s activities.

Direct Reading and Sensor Technologies Life Cycle Approach

The following lifecycle approach for the development and application of direct-reading and sensor technologies shows key steps that are taken to ensure the relevance and reliability of measurements to protect workers. The cycle begins with a clear and complete identification of what needs to be measured, under what conditions it needs to be measured, and how well it needs to be measured. It also guides research and development, prototype testing, type testing, production control testing, and training needed to develop the instrument. The life cycle approach defines procedures for acceptance testing, initial calibration, functional checks, conduct and evaluation of operational experience, maintenance and recalibration, and periodic performance testing to confirm continued successful use of the instrument. Effective prototype testing ensures that the final instrument will work as intended under realistic conditions. Documentation and continuous improvement are essential at each step.

A life cycle approach for instrumentation and methods diagram, stages of the lifecycle circle show documentation and improvement throughout

Path Forward for the 21st Century

In September 2012, The National Research Council released its report on Exposure Science in the 21st Century: A Vision and a Strategy. A major conclusion of the report was that new sensor methods and monitors will be an important driver for the future success of exposure sciences and exposure assessments. Through its activities, partnerships, and collaborations, NIOSH intends to advance the development, validation, and application of these technologies to occupational environments. Improved exposure assessments will result in enhanced health benefits for individuals and societies, but research needs must be addressed to realize this potential.

Examples of NIOSH-Developed Sensor Technologies

NIOSH has developed two smartphone applications that use sensors. The first, the Sound Level Meter App, is a tool to measure sound levels in the workplace. It also provides noise exposure parameters to help reduce occupational noise-induced hearing loss. The second, the Ladder Safety App, helps users set their extension ladder at the proper angle, among other features. Ladders are one of the leading causes of falls.

NIOSH has also developed specialized sensor technologies for use in the mining industry. The continuous personal dust monitor detects hazardous coal mine dust in the miner’s breathing space and reports this information frequently on a digital readout. The coal-dust explosibility meter helps prevent explosions caused by accumulations of combustible dusts and gases. Rather than waiting days or weeks for lab results, the meter provides real-time pass/fail assessment of coal dust. Additionally, NIOSH developed the Helmet-CAM and complementary EVADE software to identify specific work tasks where high dust exposures occur using real-time dust monitoring coupled with video.

MethAlert and MethChek technologies are NIOSH-developed, commercially available, real-time sensors for the detection of methamphetamine residues. It fills a need identified by police, fire fighters, first responders, emergency responders, and industrial hygienists for real-time surface detection methods for methamphetamine,

NIOSH Resources

Wearable Sensors: An Ethical Framework for Decision-Making
As wearable sensors become more commonplace and useful for monitoring employee safety and health, values conflict and ethical dilemmas arise that need to be addressed. This NIOSH Science Blog Post proposes an ethical framework that can be used as a decision-making tool.

2008 Direct Reading Exposure Assessment Methods (DREAM) Workshop
DHHS (NIOSH) Publication Number 2009-133
Shows the presentations and findings created with the support of 12 cosponsors and over 175 participants in the Direct-Reading Exposure Assessment Methods (DREAM) Workshop (November 13-14, 2008; Arlington, VA; Hilton Crystal City). The workshop gathered stakeholder input from academia, labor, management, developers, governmental agencies, and manufacturers on the research needs in the area of direct-reading methods for assessing occupational exposures.

Exposure Assessment Cross-Sector Program
Describes the field of exposure assessment. This program provides coordination for NIOSH efforts that identify and characterize workplace exposures, develop estimates of exposure for exposure-response and risk assessment studies, and evaluate the significance of exposure and effectiveness of intervention strategies.

Components for Evaluation of Direct-Reading Monitors for Gases and Vapors
DHHS (NIOSH) Publication Number 2012-162
Expands the historical NIOSH methods for monitor development and evaluation testing to include: performance characteristics, a summary of recommended tests to evaluate the monitors, and approximations for estimating accuracy.

Addendum to Components for Evaluation of Direct-Reading Monitors for Gases and Vapors: Hazard Detection in First Responder Environments
DHHS (NIOSH) Publication Number 2012-163
Expands the applicability of the Components document by presenting methods to be used in evaluating direct-reading monitors for hazard detection in First Responder environments, including those related to incidents involving weapons of mass destruction (WMD).

NIOSHTIC 2 Database Search
This link provides the results of a search of the NIOSHTIC-2 database for citations and abstracts of NIOSH documents related to direct-reading and sensor technology.

Other Government Resources

NSI White Paper: Nanotechnology for Sensors and Sensors for Nanotechnology: Improving and Protecting Health, Safety, and the EnvironmentExternal
This white paper details the Nanotechnology Signature Initiative on Nanotechnology for Sensors and Sensors for Nanotechnology: Improving and Protecting Health, Safety, and the Environment. The NNI agencies recognize the considerable potential for nanotechnology to open the door to the development of inexpensive, portable devices that can rapidly detect, identify, and quantify biological and chemical substances.

Information and Contact

NIOSH invites your participation to explore and further the development of new direct reading and sensor technologies to improve the health of workers and the public.

Questions, comments, and partnerships are welcome. Please contact the NCDRST Co-Director John Snawder or Co-Director Mark Hoover.