Monday, May 26, 2008

Fume Metal Fever Sec.1

OVERVIEW
Metal Fume Fever is the name for an illness that is caused primarily by exposure to zinc oxide fume (ZnO) in the workplace. The main cause of this exposure is usually breathing the fumes from welding, cutting, or brazing on galvanized metal. Metal Fume Fever is an acute allergic condition experienced by many welders during their occupational lifetimes. Studies indicate that the most common cause of metal fume fever is overexposure to zinc fumes from welding,burning, or brazing galvanized steel. Since galvanized steel is more and more common in industry, the chances of welders having to work on it are occurring more frequently all the time. Other elements, such as copper and magnesium, may cause similar effects.

EFFECTS OF OVEREXPOSURE
Zinc oxide fumes cause a flu–like illness called Metal Fume Fever. Symptoms of
Metal Fume Fever include headache, fever,chills, muscle aches, thirst, nausea, vomiting,chest soreness, fatigue, gastrointestinal pain, weakness, and tiredness. The symptoms usually start several hours after exposure; the attack may last 6 to 24 hours. Complete recovery generally occurs without intervention within 24 to 48 hours. MetalFume Fever is more likely to occur after a period away from the job (after weekends or vacations). High levels of exposure may cause a metallic or sweet taste in the mouth,dry and irritated throat, thirst, and coughing at the time of the exposure. Several hours after exposure, a low–grade fever (seldom higher than 102 F or 39 C). Then comes sweating and chills before temperature returns to normal in 1 to 4 hours. If you encounter these symptoms, contact a physician and have a medical examination /evaluation. There is no information in the literature regarding the effects of long–term exposure to zinc oxide fumes.

PERMISSIBLE EXPOSURE LIMIT (PEL)
The current OSHA standard for zinc oxide fume is 5 milligrams of zinc oxide fume per
cubic meter of air (mg/m3 ) averaged over an eight–hour work shift. NIOSH recommends
that the permissible exposure limit be changed to 5 mg/m3 averaged over a work
shift of up to 10 hours per day, 40 hours per week, with a Short–Term Exposure Limit
(STEL) of 10 mg/m3 averaged over a 15–minute period. Consult the NIOSH standard, Criteria Document for Zinc Oxide,listed in the Information Sources for more detailed information.

Fume Metal Fever Sec.2

HOW TO AVOID THE HAZARD
• Keep your head out of the fumes.
• Do not breathe fumes.
• Use enough ventilation, exhaust at the arc,or both, to keep fumes and gases from
your breathing zone and the general area.
• If adequacy of the ventilation or exhaust is uncertain, have your exposure measured
and compared to the Threshold Limit Values (TLV) in the Material Safety Data Sheet
(MSDS) for the galvanized material.
• Never take chances with welding fumes. If none of this is adequate or practical,
wear an approved respirator, air–supplied or otherwise, that adequately removes the
fumes from your breathing zone.Page 2 Fact Sheet No. 25 – 1/02

RESPIRATORS
Good safe practices recommend using engineering controls, such as local exhaust
and/or general ventilation, to reduce the exposure level to zinc oxide fumes. However, there are times when such practices and controls are not feasible, or are in the process of being installed, or are down during periods of failure. Then respirators are needed. Respirators are often used for operations in confined spaces, such as tanks or closed vessels, and in emergency situations. Always use only respirators that are approved by the Mine Safety and Health Administration (MSHA) or by the National Institute for Occupational Safety and Health (NIOSH).

Fume Metal Fever Sec.3

MONITORING AND MEASUREMENT PROCEDURES
• Eight–Hour Exposure Evaluation

Exposure measurements are best taken so the eight–hour exposure is based on a single
eight–hour sample or on two four–hour samples. Several short–time interval samples
(up to 30 minutes) may be used, but are not preferred. The air samples should be
taken by a qualified person using approved collection methods and devices. Take the
samples in the employee’s breathing zone(air that would most nearly represent that
inhaled by the employee).

• Short–Term Exposure Limit (STEL)
Evaluation Take the measurements during periods of maximum expected concentrations of zinc oxide fume. Take a 15–minute sample or a series of consecutive samples totaling 15 minutes. Collect the samples in the employee’s breathing zone (air that would most nearly represent that inhaled by the employee). Take a minimum of three
measurements on one work shift––the highest measurement taken is an estimate of
the person’s exposure.

Metal Fume Fever Sec.4

SUMMARY
Here are the main points when dealing with galvanized metal:
• Metal Fume Fever is the result ofoverexposure to zinc fumes from welding, cutting,
or brazing on galvanized steel.
• Metal Fume Fever is a short–term illness with classic flu–like symptoms.
• The permissible exposure limit (PEL)according to OSHA is 5 milligrams of zinc
oxide fume per cubic meter of air––always monitor and measure your breathing air.
• To avoid the illness, keep your head out of the fumes and do not breathe the fumes.
Use enough proper ventilation and/or exhaust. If uncertain about the ventilation,
use an approved respirator.
• There are no known long–term effects of this disease.

INFORMATION SOURCES

National Institute for Occupational Safety and Health. Criteria for a Recommended Standard – Occupational Exposure to Zinc Oxide, DHEW, NIOSH Publication No.76–104; NTIS Publication No. PB–246–693,available from National Technical Information Service (NTIS), 5285 Port Royal Road,Springfield, VA 22161.

American Welding Society (AWS) Study.Fumes and Gases in the Welding Environment,
available from American Welding Society, 550 N.W. LeJeune Road, Miami, FL33136
American Conference of Governmental Industrial Hygienists publication, Threshold
Fact Sheet No. 25 – 1/02 Page 3 Limit Values (TLV) for Chemical Substances and Physical Agents in the Workroom Environment, available from American Conference
of Governmental Industrial Hygienists (ACGIH), 1330 Kemper Meadow Drive,Cincinnati, OH 45240.

Occupational Safety and Health Administration(OSHA). Code Of Federal Regulations,
Title 29 Labor, Chapter XVII, Parts 1901.1 to 1910.1450, Order No.869–019–00111–5, available from Superintendent of Documents, U.S. Government Printing Office, P.O. Box 371954, Pittsburgh,PA 15250.

American Conference of Governmental Industrial Hygienists, Documentation of the
Threshold Limit Values and Biological Exposure Indices, available from American
Conference of Governmental Industrial Hygienists (ACGIH), 1330 Kemper Meadow
Drive, Cincinnati, OH 45240.

The following references include the specific precautionary methods used to
protect against exposure to fumes and gases:

American National Standards Institute(ANSI). Safety in Welding, Cutting, and Allied
Processes, Z49.1, available from American Welding Society, 550 N.W. LeJeune Road,
Miami, FL 33136.

National Institute for Occupational Safety and Health (NIOSH). Safety and Health in
Arc Welding and Gas Welding and Cutting,NIOSH Publication No. 78–138, available
from National Institute for Occupational Safety and Health, Robt. Taft Labs, 4676
Columbia Pkwy, Cincinnati, OH 45226.

American National Standards Institute(ANSI). Method for Sampling Airborne
Particulates Generated by Welding and Allied Processes, F1.1, available from
American Welding Society, 550 N.W. Le-Jeune Road, Miami, FL 33136.

Sunday, March 2, 2008

Occupational safety and health

From Wikipedia, the free encyclopedia

Occupational safety and health (OSH) is a cross-disciplinary area concerned with protecting the safety, health and welfare of people engaged in work or employment and entrants. As a secondary effect, OSH may also protect co-workers, family members, employers, customers, suppliers, nearby communities, and other members of the public who are impacted by the workplace environment.
Since 1950, the International Labour Organization (ILO) and the World Health Organization (WHO) have shared a common definition of occupational health. It was adopted by the Joint ILO/WHO Committee on Occupational Health at its first session in 1950 and revised at its twelfth session in 1995. The definition reads: "Occupational health should aim at: the promotion and maintenance of the highest degree of physical, mental and social well-being of workers in all occupations; the prevention amongst workers of departures from health caused by their working conditions; the protection of workers in their employment from risks resulting from factors adverse to health; the placing and maintenance of the worker in an occupational environment adapted to his physiological and psychological capabilities; and, to summarize, the adaptation of work to man and of each man to his job."
The reasons for establishing good occupational safety and health standards are frequently identified as:
• Moral - An employee should not have to risk injury at work, nor should
others associated with the work environment.
• Economic - many governments realize that poor occupational safety and health
performance results in cost to the State (e.g. through social security
payments to the incapacitated, costs for medical treatment, and the loss
of the "employability" of the worker). Employing organisations also sustain
costs in the event of an incident at work (such as legal fees, fines,
compensatory damages, investigation time, lost production, lost goodwill
from the workforce, from customers and from the wider community).
• Legal - Occupational safety and health requirements may be reinforced in
civil law and/or criminal law; it is accepted that without the
extra "encouragement" of potential regulatory action or litigation, many
organisations would not act upon their implied moral obligations.

Hazards, risks, outcomes

The terminology used in OSH varies between states, but generally speaking:
• A hazard is something that can cause harm if not controlled.
• The outcome is the harm that results from an uncontrolled hazard.
• A risk is a combination of the probability that a particular outcome will occur and the severity of the harm involved.
“Hazard”, “risk”, and “outcome” are used in other fields to describe e.g. environmental damage, or damage to equipment. However, in the context of OSH, “harm” generally describes the direct or indirect degradation, temporary or permanent, of the physical, mental, or social well-being of workers. For example, repetitively carrying out manual handling of heavy objects is a hazard. The outcome would be a musculoskeletal disorder (MSD). The risk can be expressed numerically, (e.g. a 0.5 or 50/50 chance of the outcome occurring during a year), qualitatively as "high/medium/low", or using a more complicated classification scheme.

Risk assessment

Modern occupational safety and health legislation usually demands that a risk assessment be carried out prior to making an intervention. This assessment should:
• Identify the hazards
• Identify all affected by the hazard and how
• Evaluate the risk
• Identify and prioritise the required actions
The calculation of risk is based on the likelihood or probability of the harm being realised and the severity of the consequences. This can be expressed mathematically as a quantitative assessment (by assigning low, medium and high likelihood and severity with integers and multiplying them to obtain a risk factor, or qualitatively as a description of the circumstances by which the harm could arise.
The assessment should be recorded and reviewed periodically and whenever there is a significant change to work practices. The assessment should include practical recommendations to control the risk. Once recommended controls are implemented, the risk should be re-calculated to determine of it has been lowered to an acceptable level. Generally speaking, newly introduced controls should lower risk by one level, i.e, from high to medium or from medium to low
The precautionary principle is an increasingly used method for reducing potential chemical or biological OSH risks.