Millions of U.S. workers are exposed to respirable crystalline silica in a variety of industries and occupations, including construction, sandblasting, and mining. Silicosis, an irreversible but preventable disease, is the illness most closely associated with occupational exposure to the material, which also is known as silica dust. Occupational exposures to respirable crystalline silica are associated with the development of silicosis, lung cancer, pulmonary tuberculosis, and airways diseases. These exposures may also be related to the development of autoimmune disorders, chronic renal disease, and other adverse health effects.
- Estimation of the number of workers exposed to respirable crystalline silica by industry:
Analysis of OSHA compliance data (1979‐2015)external icon
- U.S. Department of Labor Revises National Emphasis Program to Reduce or Eliminate Worker Exposure to Silica
- Crystalline silica is found in granite, artificial/engineered stone, and other stone products – Infographic
Inhaling Silica Dust Can Cause Deadly Lung Disease
- Webinar Recording
Working safely with natural and engineered stone products: Controlling worker exposure to silica dust during counter top manufacturing, finishing, and installation.
- NIOSH Science Blogs on Silica
- Morbidity and Mortality Weekly Report (MMWR)
Surveillance for Silicosis Deaths Among Persons Aged 15–44 Years — United States, 1999–2015
- CDC Preventing Silicosis
Learn about workplace solutions for controlling exposures to respirable crystalline silica in construction and hydraulic fracturing. Go to: https://www.cdc.gov/features/preventing-silicosis/index.html
- OSHA announces final rule for exposure to respirable crystalline silica
The Occupational Safety and Health Administration (OSHA) issued a final ruling for exposure to silica dust. The standard is an effort to protect workers in construction, general industry and maritime from silicosis, lung cancer, chronic obstructive pulmonary disease and kidney disease. Learn more by going to OSHA’s web siteexternal icon
Please note: For information about health effects from dust particles in environments outside of the workplace, see websites of the United States Environmental Protection Agency “Particulate Matter”external icon and the CDC “Air Pollution and Respiratory Health”.
NIOSH Publication No. 2015-106 (2015)
The Occupational Safety and Health Administration (OSHA) and the National Institute for Occupational Safety and Health (NIOSH) have identified exposure to silica as a health hazard to workers involved in manufacturing, finishing and installing natural and manufactured stone countertop products, both in fabrication shops and during in-home finishing/installation. This hazard can be mitigated with simple and effective dust controls in most countertop operations.
OSHA/NIOSH 2012pdf iconexternal icon
DHHS (NIOSH) Publication No. 2012-166 (2012)
This Hazard Alert discusses the health hazards associated with hydraulic fracturing and focuses on worker exposures to silica in the air. It covers the health effects of breathing silica, recommends ways to protect workers, and describes how OSHA and NIOSH can help.
NIOSH Alert: 1996
NIOSH Publication No. 96-112 (1996)
This Alert describes six case reports of construction workers who have died or are suffering from silicosis. In addition, the Alert cites examples of five construction operations that used poor dust controls and two operations that used good dust controls.
NIOSH Alert: Request for Assistance 1992
NIOSH Publication No. 92-102 (1992)
This Alert describes 99 cases of silicosis from exposure to crystalline silica during sandblasting. Of the 99 workers reported, 14 have already died from the disease, and the remaining 85 may die eventually from silicosis or its complications.
NIOSH Alert: 1992
NIOSH Publication No. 92-107 (1992)
This Alert describes 23 cases of silicosis from exposure to crystalline silica during rock drilling. Of the 23 workers reported, 2 workers have already died from the disease, and the remaining 21 may die eventually from silicosis or its complications.
Current Intelligence Bulletin (1981)
NIOSH Publication No. 81-137 (1981)
This report warns producers and users of silica flour that the risk of developing silicosis may be very high for exposed workers.
Occupational Health Guideline for Amorphous Silicapdf icon
This guideline is intended as a source of information for employees, employers, physicians, industrial hygienists and other occupational health professionals who may have a need for information on amorphous silica.
Occupational Health Guideline for Crystalline Silicapdf icon
This guideline is intended as a source of information for employees, employers, physicians, industrial hygienists and other occupational health professionals who may have a need for a need for information on crystalline silica.
Criteria for a Recommended Standard–Crystalline Silica
NIOSH Publication No. 75-120 (1974)
This report presents the criteria and recommended standards for preventing occupational diseases arising from exposure to crystalline variants of free silica. Criteria presented in this document do no pertain to amorphous, noncrystalline forms of silica.
Work Safety with Silica – Construction Research and Trainingexternal icon
Information on how to prevent a silica hazard and protect workers provided by the Center for Construction Reserach and Training.
NIOSH B-Reader Program
NIOSH B Reader certification is granted to physicians who demonstrate proficiency in the classification of chest x-rays for the pneumoconioses using the International Labour Office (ILO) Classification System. The NIOSH Chest Radiography Topic Page has searchable databases of NIOSH B readers and successful international examinees.
Respiratory Protection Recommendations for Airborne Exposures to Crystalline Silica
NIOSH Publication No. 2008-140 (July 2008)
NIOSH recommends the use of half-facepiece particulate respirators with N95 or better filters for airborne exposures to crystalline silica at concentrations less than or equal to 0.5 mg/m3.
NIOSH Respirators Topic Page
Provides information about respirators, including user notices, respirator selection, respirator certification processes, standards and rulemaking.
Certified Equipment List
Database of all certified respirators and coal mine dust personal sampler units.
NIOSH Hazard Review: Health Effects of Occupational Exposure to Respirable Crystalline Silica
NIOSH Publication No. 2002-129 (April 2002)
This Hazard Review describes published studies and literature on the health effects of occupational exposure to respirable crystalline silica among workers in the U.S. and many other countries. Occupational exposures to respirable crystalline silica are associated with the development of silicosis, lung cancer, pulmonary tuberculosis, and airways diseases. These exposures may also be related to the development of autoimmune disorders, chronic renal disease, and other adverse health effects.
NIOSH Manual of Analytical Methods (NMAM) (3rd Supplement)
NIOSH Publication No. 2003-154 (2003)
NMAM is a collection of methods for sampling and analysis of contaminants in workplace air, and in the blood and urine of workers who are occupationally exposed. These methods have been developed or adapted by NIOSH or its partners and have been evaluated according to established experimental protocols and performance criteria. NMAM also includes chapters on quality assurance, sampling, portable instrumentation, etc.
- NIOSH Method 7501 – Silica, Amorphouspdf icon
- NIOSH Method 7500 – Silica, Crystalline, by XRDpdf icon
- NIOSH Method 7601 – Silica, Crystallinepdf icon
NIOSH Method 7602 – Silica, Crystalline (IR)pdf icon
En Españolpdf icon
- NIOSH Method 7603 – Silica in coal mine dustpdf icon
NIOSH Pocket Guide to Chemical Hazards
Exposure limits, Respirator Recommendations, First Aid, more…
The Pocket Guide is a source of general industrial hygiene information on several hundred chemicals/classes found in the work environment. Key data provided for each chemical/substance includes name (including synonyms/trade names), structure/formula, CAS/RTECS Numbers, DOT ID, conversion factors, exposure limits, IDLH, chemical and physical properties, measurement methods, personal protection, respirator recommendations, symptoms, and first aid.
Spirometry Monitoring Technology
NIOSH topic page with link to software for Spirometry Longitudinal Data Analysis (SPIROLA).
Information about the NIOSH Spirometry Training Program for individuals who administer spirometry tests to workers exposed to cotton, coal, or silica dusts.
Occupational Respiratory Disease Surveillance (ORDS)
NIOSH Topic Page about occupational respiratory disease medical screening and monitoring.
Atlas of Respiratory Disease Mortality, United States: 1982-1993
NIOSH Publication No. 98-157 (1998)
This report presents maps showing geographic distributions (by health service area) of mortality associated with selected respiratory conditions that together represent nearly all respiratory diseases. For categories of traditional occupational lung diseases mapped in this atlas (i.e., the pneumoconioses, including coal workers’ pneumoconiosis, asbestosis, silicosis, byssinosis, and other and unspecified pneumoconioses), nearly all cases are attributable to hazardous occupational exposure.
MMWR: Morbidity and Mortality Weekly Reports
The MMWR weekly contains data on specific diseases as reported by state and territorial health departments and reports on infectious and chronic diseases, environmental hazards, natural or human-generated disasters, occupational diseases and injuries, and intentional and unintentional injuries. Included here are a collection of articles related to occupational exposure to silica.
Summary of Notifiable Noninfectious Conditions and Disease Outbreaks — United Statespdf icon
Morbidity and Mortality Weekly Report: October 23, 2015 /62;54:81-5
Surveillance for Silicosis — Michigan and New Jersey, 2003–2010
Morbidity and Mortality Weekly Report: October 23, 2015 /62;54:81-5
Update: Silicosis Mortality – United States, 1999-2013
Morbidity and Mortality Weekly Report: June 19, 2015 /23;64:653-4
Silicosis Mortality Trends and New Exposures to Respirable Crystalline Silica – United States, 2001-2010
Morbidity and Mortality Weekly Report: February 13, 2015 / 15;64:117-20
Notes from the Field: Silicosis in a Countertop Fabricator – Texas, 2014
Morbidity and Mortality Weekly Report: February 13, 2015 / 64:129-30
Coal Workers’ Pneumoconiosis-Related Years of Potential Life Lost Before Age 65 Years — United States, 1968–2006
Morbidity and Mortality Weekly Report: December 25, 2009 / 58(50);1412-1416.
Silicosis-Related Years of Potential Life Lost Before Age 65 Years — United States, 1968–2005
Morbidity and Mortality Weekly Report: July 18, 2008 / 57(28);771-775.
Silicosis Deaths Among Young Adults — United States, 1968-1994
Morbidity and Mortality Weekly Report: May 1, 1998 / 47(16);331-335.
Silicosis Mortality, Prevention, and Control — United States, 1968–2002
Morbidity and Mortality Weekly Report: April 19, 2005 / 54(16);401-405.
Silicosis in Dental Laboratory Technicians — Five States, 1994–2000
Morbidity and Mortality Weekly Report: March 12, 2004 / 53(09);195-197.
Fatal Illnesspdf icon
NIOSH Publication No. 2002-118
Nonfatal Illnesspdf icon
NIOSH Publication No. 2002-120
Focus on Miningpdf icon
NIOSH Publication No. 2002-121
Work-Related Lung Disease (eWoRLD) Surveillance System
The Work-Related Lung Disease (eWoRLD) Surveillance System, produced by the National Institute for Occupational Safety and Health (NIOSH), presents up-to-date summary tables, graphs, and figures of occupationally-related respiratory disease surveillance data on the pneumoconioses, occupational asthma and other airways diseases, and several other respiratory conditions. For many of these diseases, selected data on related exposures are also presented.
Through the NIOSH Worker Notification Program , NIOSH notifies workers and other stakeholders about the findings of past research studies related to a wide variety of exposures. The links below present archival materials sent to participants in studies related to crystalline silica exposure.
A Guide To Working Safely With Silica: If It’s Silica, It’s Not Just Dust (1997)pdf icon
This guide, a cooperative effort between the Department of Labor and NIOSH, explains how you can protect yourself and others if you work in one of the dozens of industries where dust containing silica is present.
Press Release on Joint Campaign on Silicosis Preventionexternal icon
Reprint of original press release from the U.S. Department of Labor – Office of Public Affairs