Silica - It’s Not Just Dust!

1
Silica - Its Not Just Dust!

• by
• Mary E. Reed, ARM, CSP
• Argonaut Insurance Company

2
Why Target Crystalline Silica Exposure?

• Widespread Occurrence and use -
• Maritime
• Agriculture
• Construction
• General Industry
• Number of Related Deaths
• Number of exposed workers
• Health Effects

3
Occurrence of Crystalline Silica

• Silicon Dioxide is basic component of sand,
  quartz, granite
• Quartz is second most common mineral in earths
  crust

• Airborne silica is produced by, among other
  activities
• Sandblasting
• Rock Drilling
• Roof Bolting
• Foundry Work
• Stone Cutting
• Drilling
• Quarrying
• Tunneling

4
Industries with Silica Exposure

• Electronics
• Foundries
• Ceramics, clay pottery, stone, glass
• Construction
• Agriculture
• Maritime
• Mining

• Railroad ( setting laying track)
• Slate flint quarrying flint crushing
• Use manufacture of abrasives
• Manufacture of soap detergents

5
Number of Silica Related Deaths

• Total US deaths 1968-1990 where silica is
  reported on death certificate 13,744 people
• Deaths where silicosis is reported as underlying
  cause of death 6,322 people
• 68 of silica related deaths reported in 12
  states
• 10 of silica-related deaths reported from
  construction industry

6
Number of Exposed Workers

• NIOSH Hazard Alerts estimate
• More than One Million Workers at Risk
• More than 1,00,000 sandblasters

7
Health Effects

• Pulmonary fibrosis (silicosis)
• Acute silicosis (1 to 3 years)
• Accelerated silicosis (3 to 10 years)
• Chronic silicosis (5 to 25 years)
• Possible Lung Cancer

8
Inspection Targeting

• Wherever possible, inspections will be focused to
  particular establishments where known exposures
  to crystalline have occurred or there are known
  cases of silicosis
• Process
• Identify establishments
• Select sites by use of random number tables
• Numbers of Inspections determined by regions
• Sites with effective control programs are exited
  after program review

9
Examples of Potential Data Sources for Targeting

• Workers Compensation Data
• OSHA 200 data
• SENSOR - NIOSH cooperative agreements with
  state agencies
• State surveillance data
• Hospital discharge data
• OSHA data on industries with historic exposure to
  crystalline silica

10
Additional Information Sources for Construction

• Visual observations of relevant processes
• Dodge reports
• University of Tennessee construction activity
  reports

11
Elements of an effective, On-going Control
Program for Crystalline Silica

• Personal Monitoring
• Medical Surveillance
• Training
• Availability of monitoring/Surveillance data to
  workers
• Respiratory Protection Program
• Hygiene facilities clothing change areas

12
Elements of Control Program (continued)

• Recordkeeping
• Exposures below PEL or a current program with
  interim protection
• Housekeeping
• In construction A Safety Health Program
• Regulated areas to limit exposures

13
The Hawks Nest Incident - Americas Worst
Industrial Disaster by Martin Cherniack, MD

• The Hawks Nest Tunnel - Union Carbide New
  Kanawha Power Corp.
• Rinehart Dennis, Charlottesville, VA.
• Gauley Bridge, West Virginia
• Drilling a tunnel for power production
• Close to 1000 workers lost their lives because of
  acute silicosis