ECI – Engineers Construction

High voltage is deadly.  There have been two recent fatalities in Vermont that have involved workers being electrocuted by high voltage.

Whenever we work around power, we need to identify the risk and have a plan in the tailboard to eliminate that risk.  The OSHA Construction Standard (Part CC) includes separate minimum clearances for cranes and the Mechanized Equipment Standard (Part O) is for all other equipment (excavators, concrete pumper booms, loaders, etc).   The Crane Standard minimum clearance chart is easier to use since it does not involve a calculation to compute the minimum clearance:

Reference:  OSHA Construction Standard 1926.1408 (H)

In addition to recognizing, the daily tailboard should include provisions to prevent violating these clearances, as considered in the Crane Standard.  Such provisions might include:  a dedicated spotter with direct communication to the operator, marking delineation, or barriers to prevent operations from entering into a restricted zone.   Other helpful measures include:  ”High Voltage Overhead” signage and protective covers on the conductors (installed by power company).

For crane work, we have a tailboard form that includes these specific clearance criteria: Pre-Lift Checklist.  A major difference between the Crane Standard and the Mechanized Equipment Standard is that cranes can not be operated under power lines if the boom is capable of reaching into the minimum clearances.

Our work frequently involves demolition of existing utilities, particularly water, sewer, power, and communication lines.  Our duties for these demolition tasks include verification that the line is the correct utility and that it’s ready for demolition (out of service and de-energized).  We should always confirm this with our client, the utility owner, and through our own evaluation.   We should also notify the utility owner of the demolition schedule to allow for them to be present and, in some cases, we might strongly suggest their presence.

Occasionally, demolition becomes necessary for an apparently abandoned utility that  isn’t indicated as such on any contract document.  It is reasonably safe for us to assume that utilities designated on the drawings as demolish or remove have some type of approval from the utility owner.  Without that implied permission, we need to request permission from the utility owner to demolish their property.  ECI’s Utility Demolition Permit was developed to verify the utility owner’s permission and to establish basic de-energization requirements.

From ECI’s Safety Manual:

26 Utility Demo Protocol

27 Utility Demo Form

Exothermic welding (also known as cad and thermite or CAD welding) is frequently used for bonding electrical conductors for grounding.  The process has an obvious risk of burn injuries and the potential to start an unintentional fire.

The process involves an exothermic reaction (reaction that yields energy) between aluminum powder and copper oxides.  The reaction is triggered with a spark to a magnesium booster that develops sufficient heat to start the reaction.  The molten copper rapidly reaches temperatures of around 1,400 degrees C and penetrates around the copper wire to form a bond.  Exothermic welding is also used in splicing rail, only at a much larger size and different metal compositions.

The important safety concerns include:

• Proper PPE:  safety glasses, gloves, leather boots
• Clearing the area of flammable materials;  keep fire extinguisher handy
• Inspect Molds:  clean, dry, proper size, in good condition (replace when worn).
• Protecting the materials from moisture (a drop of rain can cause a violent and dangerous reaction)
• Keep unused shots separated from the one being ignited (particularly important for railroad shots)
• Storing all welds in cool, dry locations and in properly labeled boxes.
• Keeping a copy of the MSDS sheet on file and on site.

When possible, use only totally contained electrically triggered welds such as the Cadweld Plus or Harger UltraShot.  When using the old-style torch/spark-ignited powder shots and the thermite rail shots, additional PPE is necessary including face shield and welding gloves (consider  jacket & chaps).  Additional fire protection measures are also necessary on rail shots because of the size of the shots and since it may not be possible to completely clear the are of flammable materials (e.g., timber cross ties).

Harger UltraShot being fired off on an ECI Project

Thermite Rail Weld

Harger Ultra Shot

Revised 5/3/12  kap

This week’s safety focus involves personal wellness.  All of us are susceptible to a variety of cardiovascular diseases which, if untreated, can reduce the quality of, or shorten our lives.  The following Center of Disease Control website provides a very complete discussion on the topic:

http://www.cdc.gov/dhdsp/

A good start to a healthy cardiovascular system involves:

• Avoid tobacco products
• Exercise aerobically for 30 minutes on a daily basis
• Visit your doctor and get regular screening for blood pressure, cholesterol, and diabetes
• Eat a healthy balanced diet and maintain a healthy weight

This weeks safety focus is Cargo Securement, which is extremely important in protecting the traveling public. Therefore, only properly trained ECI drivers should be transporting any heavy equipment.

For smaller loads (under a 1,000 lbs.) it is generally acceptable to use 2 ratchet straps for load securement.

The regulations are complicated, so if you don’t know the rules purtaining to securement of your load, refer to one of the following references:

• Ask the safety department, Kim, Scott, Luc, or other qualified driver, or
• Refer to the DOT Cargo Securement Regulations reference on the ECI Document Library (www.engineersconstruction.com/employee-portal/document-library)

Despite the emergency shutdown features on a wood chipper, 39 deaths occurred from 1996 to 2005 in the workplace involving a wood chipper.

OSHA has a “Safety & Health Information Bulletin” on wood chippers:  OHSA on Wood Chippers

The basic safety precautions for safe operation of a wood chipper includes:

• Thoroughly familiarize yourself with the operators manual including safe practices for feeding the chipper.
• Prior to use, inspect the chipper.  Verify that the emergency shutdown systems are operational and that all guards are in place and secure.
• Wear the proper PPE, including gloves, forestry helmet, boots
• Use the manufactures lock-out procedures whenever working on the equipment

Of the fatalities referenced in the OSHA Bulletin, one occurred because the operators glove cuff got caught in the brush and another occurred while using a chipper with a winch system that got caught in the cutter drum and recoiled back at another worker.

OSHA has a Standard for Hazard Communication which is essentially the requirements for informing employees on the hazards for chemicals in the workplace, labeling, training, and MSDS sheets (now called Safety Data Sheets).

The changes are described on the following webpage: Hazard Communication Standard

Major changes to the Hazard Communication Standard

• Hazard classification: Provides specific criteria for classification of health and physical hazards, as well as classification of mixtures.
• Labels: Chemical manufacturers and importers will be required to provide a label that includes a harmonized signal word, pictogram, and hazard statement for each hazard class and category. Precautionary statements must also be provided.
• Safety Data Sheets: Will now have a specified 16-section format.
• Information and training: Employers are required to train workers by December 1, 2013 on the new labels elements and safety data sheets format to facilitate recognition and understanding.