Chapter 4:Environmental Hazards

Lead

Can you name some materials in a house that might contain lead?

What is Lead?

49In

Indium114.82

50SnTin

118.69

51Sb

Antimony121.75

81Tl

Thallium204.37

82Pb

Lead207.19

83Bi

Bismuth208.980

•Chemical element •Pb: Latin “Plumbum” •Plumber, Plumb bob•Heavy,soft (malleable) metal

What’s the Matter with Lead?

• Highly toxic poison

• Accumulates in body tissues

• Harms many body systems– blood– nerves, brain– reproductive

How Can I Be Exposed to Lead?

• Deteriorated lead paint

• Burning or cutting metals containing or painted with lead– Plumbing lines– Solder joints– Corrosion resistant

metal coatings

What Steps Do I Take First?

• Before you begin work, have a “Competent Person” determine if workers will be potentially exposed to lead

• If workers are potentially exposed, determine if the concentration of these exposures exceeds OSHA limits

• If workers conduct “Trigger Tasks”, certain controls are required

TRIGGER TASK 1 (< 10 x the PEL)

• Manual demolition of structures

• Hand scraping or sanding

• Heat guns

• Using power tools with dust collection systems

• Spray painting

TRIGGER TASK 2 (10-50 X PEL)

• Using power tools without dust collection systems attached

• Movement/removal of enclosures

• Cleanup where dry expendable abrasives are used

• Lead containing mortar, rivet busting

TRIGGER TASK 3 (>50 x the PEL)

• Abrasive blasting

• Welding or torch cutting metals containing lead or lead based paint

Respiratory Protection(Minimum requirements)

• Trigger task 1– ½ mask air purifying respirator with high

efficiency filters (HEPA)

• Trigger task 2– Full face piece respirator with high

efficiency filters (HEPA)

• Trigger task 3– Supplied air pressure/demand respirator

Other Requirements

• Personal protective clothing, such as disposable jump suits

• Change areas for work clothing and shoes

• Hand washing facilities

• Biological monitoring (Blood Lead)

• Training

METHODS OF COMPLIANCELead in Construction

• Exposures > PEL (From Day One)

– Engineering Controls

– Respiratory protection

– Compliance program

– Mechanical ventilation

– Administrative controls

– Good work practices

Silica

Silica

• What is Silica?

• Where is it found on construction sites?

• When does silica become hazardous?

What are the Health Effects of Silica?

• Silicosis• Affects alveolar

surface of lungs– Decreases elasticity– Prevents oxygen/CO2

exchange

• Lung X-ray is required to diagnose silicosis

• Silica also contributes to tuberculosis, heart disease, and lung cancer

What Jobs Cause Exposure?

• Cutting concrete slabs• Finishing and grinding on

concrete• Block and brick cutting• Jack hammering on

concrete• Abrasive blasting

Control Silica Using Wet Methods

• Water suppression of dust is effective

• Minimal water use is required

• Planning for water supply is required

Using Ventilation to Control Dust

• Use when wet methods are not feasible

• Collect dust at the source

• Supplement with respirators

• Avoid contaminating co-workers

Asbestos

Asbestos

1. Surfacing Material

2. Thermal System Insulation (TSI)

3. Miscellaneous

Photo: oldhouseweb.com

Health Effects of Exposure to Asbestos

• Asbestos exposure can cause:

– Asbestosis

– Mesothelioma

– Lung Cancer

– Other Illnesses/Cancers

FEDERAL ASBESTOS REGULATIONS

(Occupational Exposures)

1. OSHAAsbestos in Construction

Asbestos in General Industry

2. EPAWorker Protection Rule

Major Elements of OSHA’s Asbestos Standard 29 CFR 1926.1101 (Construction)

– Exposure monitoring• Permissible Exposure Limit (PEL) of 0.1

f/cc, 8 hour TWA• Excursion Limit of 1.0 f/cc, 30 minutes

– Employee training and education– Regulated areas

Major Elements of OSHA’s Asbestos Standard (cont.)

– Defines 4 Classes of work activity

• Training for each class of work activity

– Engineering and work practice controls

– Protective equipment

– Medical surveillance

– Recordkeeping

MOLD

Mold• Molds are

microscopic organisms found everywhere.

• Some molds can cause adverse health effects.

How to Recognize Mold

• Sight—Usually appears as colored woolly mats

• Smell—Often produces a foul, musty, earthy smell

Hidden Mold in Buildings

                              

How to Protect Yourself

• Avoid mold spores

• Use respiratory protection.

• Protect your skin

How to Protect Yourself (continued)

• Wear goggles

• Avoid getting

mold or mold spores in your eyes.

Cleanup of Mold

• Disinfect hard, water resistant, non-porous surfaces

• Consider discarding water-damaged porous materials.

• After working with mold-contaminated materials, wash thoroughly, including the hair, scalp, and nails.

Regulation of Mold Cleanup

• No exposure limits

• No federal rules

• State and local rules may apply

• State/local certification may apply

• Specific contractual obligations may apply