Free OSHA Course- Health Hazards in Construction- Chemical Hazards.
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Free OSHA Course- Health Hazards in Construction- Chemical Hazards.

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Health Hazards in Construction- Chemical Hazards.

This module gives a general overview of the various health hazards to which construction workers may be exposed. Specifically, upon completion of this training, you will be able to:

  • Identify major health hazards common to the construction industry
  •  Describe both acute & chronic health hazards
  • Protect themselves from safety & health hazards
  • Recognize employer requirements and to protect workers from
  • exposure to safety & health hazards.

- Introduction.

- Construction Diversity.

Construction work is dynamic, diverse, and constantly changing. This poses a great challenge in protecting the safety and health of construction workers. Construction workers are at risk of exposure to various health hazards that can result in injury, illness, disability, or even death.

- Risk Factors in Construction.

  • Factors increasing the health risk of construction workers include:
  • Constantly changing job site environments and conditions
  • Multiple contractors and subcontractors     
  • High turnover; unskilled laborers
  • Constantly changing relationships with other work groups
  • Diversity of work activities occurring simultaneously
  • Exposures to health hazards resulting from own work as
  • Well as from nearby activities (“bystander exposure”)

- Health Hazard Categories.

Four major categories of health hazards to which construction workers may be exposed:

  • Chemical Hazards (i.e. dusts, mist, fumes, gases, and vapors)
  • Physical Hazards (i.e. heat, noise, vibration)
  • Biological Hazards (i.e. plants, insects, animals, and microorganisms)
  • Ergonomic Hazards (i.e. awkward postures and lifting, pushing, and pulling).

Note: Ergonomic hazards are the most frequently occurring health hazards in construction and the cause of most injuries.

Some Examples of Construction Health Hazards.

Occupations

Potential Health Hazards

Brick masons

Cement dermatitis, awkward postures, heavy loads

Drywall installers

Plaster dust, heavy loads, awkward postures

Electricians

Heavy metals in solder fumes, awkward posture, heavy

loads, asbestos

Painters

Solvent vapors, toxic metals in pigments, paint additives

Pipefitters

Lead fumes and particles, welding fumes, asbestos dust

Carpet layers

Knee trauma, awkward postures, glue and glue vapor


- Chemical Hazards.



Chemicals can exist in the form of:

  • dusts, fumes, fibers (solids)
  • liquids,
  • mists
  • gases,
  • vapors

Chemicals are found in variety of products used at construction sites. Workers may also be exposed to chemicals generated during construction activities.

Examples of chemical hazards found in construction work:

  • asbestos
  • lead
  • silica
  • cadmium
  • carbon monoxide 
  • welding fumes
  • spray paints
  • cutting oil mists
  • solvents
  • hexavalent chromium

- Routes of Exposure.

Chemicals can enter the body through:

  • Inhalation: breathed in (Inhalation is typically the most common way chemicals can enter the body in a work situation.)
  • Ingestion: accidental swallowing through eating, drinking, or smoking
  • Absorption: absorbed through contact with skin or eyes

- Acute vs. Chronic.

There are generally two types of health effects from chemical exposure, acute and chronic.

- Acute.

Appears immediately or within short time following exposure, (minutes or hours); death possible from some hazardous substances.

Typically, sudden, short-term, high concentration.

Examples:

  • Headache, collapse, or death from high levels of carbon monoxide
  • Eye and throat irritation from exposure to ammonia
  • Death and/or serious injury resulting from exposure to Hydrogen

- Chronic.

Usually develops slowly, as long as 15-20 years or more.

Continued or repeated for a prolonged period, usually years.

Examples:

  • Lung cancer, asbestosis, mesothelioma from exposure to asbestos
  • Silicosis from exposure to crystalline silica
  • Leukemia from exposure to benzene

- Asbestos.

Construction workers may be exposed to asbestos during demolition or remodeling of older buildings built before 1980 which can contain asbestos insulation, or other asbestos containing products.

Asbestos removal can only be done by specially trained asbestos workers.

Asbestos exposure can cause breathing problems, lung cancer and cancer of the lung lining many years after exposure.

- Welding Fumes.

Welding fumes contain a variety of chemicals depending on what is being welded on, chemical makeup of welding rods, fluxes and shielding gases.

Generally, welding in confined spaces or welding on stainless steel which generates hexavalent chromium, are the most hazardous welding activities.


- Chromium Hexavalent (CrVI).

Hexavalent chromium compounds, exist in several forms:

  • Industrial uses of hexavalent chromium compounds include chromate pigments in dyes, paints, inks, and plastics; chromates added as anticorrosive agents to paints, primers, and other surface coatings; and chromic acid electroplated onto metal parts to provide a decorative or protective coating.
  • Hexavalent chromium can also be formed when performing "hot work" such as welding on stainless steel or melting chromium metal.
  • Health Effects of hexavalent chromium exposure include: Lung cancer; Asthma; Nasal perforation, ulceration, and dermatitis. 


- Solvents.

Millions of workers are exposed to solvents daily.

Health hazards associated with solvent exposure include toxicity to the nervous system, reproductive damage, liver and kidney damage, respiratory impairment, cancer, and dermatitis.

Solvents share many chemical, physical, and biological properties that warrant national attention be directed to them as a group.

Many solvent groups or individual substances have special properties requiring more specialized control measures.

A variety of solvents with varying degrees of toxicity are used in construction, they are in paints, glues, epoxies, and other products.

Generally, the possibility of exposure to excessive amounts of solvent. vapors is greater when solvents are handled in enclosed or confined spaces.

Solvents can:

  • Irritate your eyes, nose, or throat.
  • Make you dizzy, high, sleepy, give you a headache or cause you to pass out.
  • Affect your judgment or coordination, Cause internal damage to your body.
  • Dry out or irritate your skin.

- Crystalline Silica.

What is crystalline silica?

Crystalline silica is a basic component of soil, sand, granite, and many other minerals.

Quartz is the most common form of crystalline silica.

Cristobalite and tridymite are two other forms.

All three forms may become respirable size particles when workers chip, cut, drill, or grind objects that contain crystalline silica.

- Hazards of crystalline silica.

Seriousness of the health hazards associated with silica exposure is demonstrated by the fatalities and

disabling illnesses that continue to occur in sandblasters and rock-drillers.

Has been classified as a human lung carcinogen.

Breathing crystalline silica dust can cause silicosis, which in severe cases can be disabling, or even fatal.

- Symptoms of silicosis.

  • Chronic/classic silicosis: 15–20 years of moderate to low exposures; symptoms may or may not be obvious; chest x-ray to determine if there is lung damage; worker may experience shortness of breath upon exercising and have clinical signs of poor oxygen/carbon dioxide exchange.
  • Accelerated silicosis: 5–10 years of high exposures to respirable crystalline silica. Symptoms include severe shortness of breath, weakness, and weight loss.
  • Acute silicosis: a few months or as long as 2 years following exposures to extremely high concentrations of respirable crystalline silica. Symptoms of acute silicosis include severe disabling shortness of breath, weakness, and weight loss, which often leads to death.

- Where are construction workers exposed?

  • Many different construction activities.
  • Most severe exposures generally occur during abrasive blasting with sand to remove paint and rust from bridges, tanks, concrete structures, and other surfaces. 
  • Other construction activities that may result in severe exposure include jack hammering, rock/well drilling, concrete mixing, concrete drilling, brick and concrete block cutting and sawing, tuck pointing, tunneling operations

- Protect against exposures to crystalline silica.

  • Replace crystalline silica materials with safer substitutes, whenever possible.
  • Use engineering or administrative controls, where feasible, such as local exhaust ventilation and blasting cabinets.
  • Use protective equipment or other protective measures (e.g. respiratory protection).
  • Use all available work practices to control dust exposures (e.g. water sprays).
  • Wear disposable or washable work clothes and shower if facilities are available. Vacuum the dust from your clothes (with a HEPA vacuum) or change into clean clothing before leaving the work site.
  • Participate in training, exposure monitoring, and health screening and surveillance programs to monitor any adverse health effects.
  • Do not eat, drink, smoke, or apply cosmetics in areas where crystalline silica dust is present and wash your hands and face outside of dusty areas before performing any of these activities.

- Lead.

Construction workers are and can be exposed to lead during many constructions related activities to include:

  • Demolition of structures.
  • Flame-torch cutting.
  • Welding.
  • Use of heat guns, sanders, scrapers, or grinders to remove lead paint.
  • Abrasive blasting of steel structures.
  • Excavation work in areas with lead contamination (e.g. burn pits and landfills)
  • Other construction and hazardous waste related activities.

- How You Can Become Exposed to Lead.

Lead is an ingredient in thousands of products widely used throughout industry, including lead-based paints, lead solder, electrical fittings and conduits, tank linings, plumbing fixtures, and many metal alloys.

Although many uses of lead have been banned, lead-based paints continue to be used on bridges, railways, ships, and other steel structures because of its rust- and corrosion-inhibiting properties.

Also, many homes were painted with lead-containing paints.

Significant lead exposures can also occur when paint is removed from surfaces previously covered with lead-based paint.

OSHA has very strict regulations for worker exposure to lead.

Major Elements of OSHA’s Lead Standard:

A permissible exposure limit (PEL) of 50 micro-grams of lead per cubic meter of air, as averaged over an 8-hour period.

Requirements for engineering controls and work practices, where feasible, to reduce worker exposure.

Requirements for good personal hygiene practices, such as washing hands before eating and taking a shower before leaving the worksite.

Requirements for protective clothing and, where necessary, with respiratory protection.

A requirement that employees exposed to high levels of lead be enrolled in a medical surveillance program.

- Confined Spaces.

Exposure to chemicals or lack of oxygen in confined spaces can be deadly.

Airborne chemicals can quickly reach dangerous levels in confined spaces that are not ventilated.

Carbon monoxide, hydrogen sulfide, welding fumes and solvent vapors are typical confined space chemical hazards.

In some confined spaces, oxygen deficiency will cause the person entering to instantly collapse.

As many co-workers who attempt rescue die in confined spaces as the original worker who collapsed.

- Hazard Communication.

  - HazCom Background

Hazard Communication (HazCom) = Right To Know

Ensures that hazards of all chemicals produced or imported are evaluated, and that information concerning their hazards is transmitted to employers and employees.

Transmittal of information includes container labeling and other forms of warning, materials safety data sheets, and employee training.

The HazCom standard establishes uniform requirements to make sure the hazards of all chemicals in the workplace are evaluated and the information is passed on to affected.

- How HazCom Works.

Chemical Manufacturers Must:

Determine the hazards of each product; and communicate information to customers through labels and Material Safety Data Sheets (MSDS).

Employers Must:

Identify and list chemicals in the workplace; obtain MSDSs and labels for each chemical; and develop and implement written programs that include chemical lists, labels, MSDSs, personal protective equipment (PPE), and employee training.

 Employees Must:

Comply with all elements of the HazCom program by following the warnings, cautions on MSDSs and on chemical labels; and wear and maintain required PPE.

- Training.

Employee training plans must include general and site-specific information:

  • How the HazCom program is implemented.
  • Hazards of the chemicals in the area.
  • Measures employees can take to protect themselves.
  • Location and use of PPE, if required.
  • Methods and observations workers can use to detect the presence of a chemical.

- Labels and Warnings.

 Each container must be labeled, tagged, or marked with the identity of the chemical   contained, and must show appropriate hazard warnings.

 Labels must be legible, in English, and prominently displayed.


- SDS.

Old terminology for many years was MSDS or Material Safety Data Sheet under GHS, the new terminology is Safety Data Sheet (SDS) and provides comprehensive information for use in workplace chemical management.

The documents provides information and advice on safety precautions.

The new SDS should contain 16 heading as per below figure.


So, what do you do if you find a chemical in your workplace and after reading the label still are not sure how you should handle it? You should consult the safety data sheet or SDS for the chemical.

There should be one available from every chemical you might encounter and if there is not, then request one immediately.

- Material Safety Data Sheets (MSDSs).

Chemical manufacturers must:

  • Develop an MSDS for each chemical they produce or import.
  • MSDS must be provided automatically at the time of the initial shipment of the product.
  • MSDS must be in English and include information regarding the chemical identity.

Information must be provided:

  • On the characteristics, both physical and chemical.
  • Known acute and chronic health effects and related health information.
  • Exposure limits.
  • Whether the chemical is considered to be a carcinogen.
  • Precautionary measures.
  • Emergency and first-aid procedures.
  • The identification of the organization that prepared the MSDS.

Some items that must be included on an MSDS:

  • The characteristics of the chemical, both physical and chemical Known acute and chronic health effects and related health information.
  • Exposure limits.
  • Whether the chemical is a carcinogen.
  • Precautionary measures.
  • Emergency and first-aid procedures. The identification of the organization that prepared the MSDS.


















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