Chain Saw Safety Specialists

Posts Tagged ‘chain saws’

the definition of a proper notch is sometimes confusing or misunderstood for a variety of reasons. Loggers may not realize how a proper notch works and why it is so important in directional felling and in maintaining the quality of the tree being cut. Some carry on from generation to generation, even though the tools and methods are drastically different now than they were even a generation ago. Some have developed techniques from other loggers. They continue to use them even though they may or may not be best for the situation at hand because it’s all they know. Yet, there are others who do a great job of notching to be sure their tree goes where it’s supposed to without damage to that valuable butt log, or to residual stands.

 

So let’s describe the different types of notches, and the advantages and disadvantages of each. There are three types of notches commonly used in the logging industry by chainsaw operators in tree felling:

 

1. Conventional notch (35 degrees plus or minus open )

Advantages:

* Most commonly used and recognized

* Almost everyone has seen it and knows how to cut it.

Disadvantages:

* Easy to bypass the cuts

* Opening is not wide enough – allowing the two face cuts to contact one another prior to the tree hitting the ground, allowing stump pull, side scarring, or worst case scenario – barber chairing.

* Much easier to cut the hinge off, since the back cut must be made above the notch cut, making judgement of the thickness of the hinge difficult.

 

2. Humbolt Notch (45 degree open)

 

Advantage(s)

* Allows the butt log to be cut without the notch cut being taken out of the log, allowing the butt log to be cut evenly and maintaining the full circumference of the log

 

Disadvantage(s)

* Infrequently used, especially in the Midwest, so it is not easily recognized.

* Difficult to match the two notch cuts because of the method required to cut it.

* Cannot cut the stumps as low as the other techniques because the angled cut needs to be taken out of the stump.

* The opening is not wide enough, allowing the two face cuts to contact one another prior to the tree hitting the ground, allowing stump pull, side scarring, or worst case scenario – barber chairing.

 

3. Open Face Notch (70 degrees or more)

 

Advantages:

* Much easier to match the two notch cuts, allowing the notch to work during the entire travel of the tree to the ground

* Allows the tree to fall almost completely to the ground before the two notch cuts make contact, reducing the possibility of stump pull, side scarring, or barber chairing.

* Because the bore cut is recommended in combination with the open face notch, setting the hinge width and thickness is made much easier, allowing for directional felling, and allowing the tree and stump to hold together longer, giving the feller more time to retreat into his/her escape route before the tree releases.

Disadvantages:

* Relatively new process, so not fully understood or recognized as effective.

 

When cutting notches, regardless of the type used, the following are some requirements in order for them to work properly.

 

If using the conventional or Humboldt notches, the opening must be a minimum of 45 degrees. The depth of the notch cut should be approximately 1/3rd the diameter of the tree’s DBH (diameter – breast height) The minimum width of the notch should be a minimum of 80% of the trees’ DBH. The two notch cuts MUST match at the back of the notch –bypassing one cut with the other allows the bypass to create a fulcrum which can cause stump pull, side scarring, or barber chairing.

 

If using the open face notch, the opening must be a minimum of 70 degrees – and 90 degrees is optimum. The depth of the notch is achieved when the width of the notch cut reaches 80 % of the diameter of the trees’ DBH. If the tree has side lean that must be controlled, a deeper notch to achieve a longer hinge is recommended. Again, the two notch cuts must match in order for the notch to work properly.

 

All of the notches above are acceptable and will work if cut properly. No matter which notch you choose, if it isn’t cut right, will not work right. And the other element that makes them work properly is the type of back cut used with each one. It is essential that hinge wood is left no matter which notch is used, . It has been our experience and it has been shown that the open face notch in combination with the boring technique will allow the sawyer to have better control of the tree, increase the value of the tree, and be safer in his everyday activities.

 

Working Safely with Chain Saws

 

 

 

The chain saw is one of the most efficient and productive portable power tools used in the industry.  It can also be one of the most dangerous.  If you learn to operate it properly and maintain the saw in good working condition, you can avoid injury as well as be more productive.
 
 
 
 

Approved OSHA Equipment

Ideal OSHA Equipment

 
 
 
 

Before Starting the Saw

•  Check controls, chain tension, and all bolts and handles to ensure they are functioning properly and adjusted according to the manufacturer’s instructions.
• Fuel the saw at least 10 feet from sources of ignition.
• Check the fuel container for the following requirements:
• Must be metal or plastic
• Must not exceed a 5 gallon capacity
• Must be approved by the Underwriters Laboratory, Factory Mutual (FM), the Department of Transportation (DOT), or other Nationally Recognized Testing Laboratory.

While Running the Saw

• Keep hands on the handles, and maintain secure footing while operating the chainsaw.
• Clear the area of obstacles that might interfere with cutting the tree or using the retreat path.
• Do not cut directly overhead.
• Shut off or release throttle prior to retreating.
• Shut off or engage the chain brake whenever the saw is carried more than 50 feet, or across hazardous terrain.
• Be prepared for kickback; use saws that reduce kickback danger (chain brakes, low kickback chains, guide bars, etc.).

Personal Protective Equipment

Chain Saw Safety Equipment Requirements

Personal protective equipment (PPE), for the head, ears, eyes, face, hands, and legs are designed to prevent or lessen the severity of injuries to loggers and other workers using chain saws.

• PPE must be inspected prior to use on each work shift to ensure it is in serviceable condition
• The following PPE must be used when hazards make it necessary:
• Head Protection
• Hearing Protection
• Eye/Face Protection
• Leg Protection
• Foot Protection
• Hand Protection

Chain Saw Safety Training

Employers involved in tree removal/logging are required to assure that their employees are able to safely perform their assigned tasks. When loggers are trained to work safely they should be able to anticipate and avoid injury from the job related hazards they may encounter.

Chain Saw Safety Training requirements include:

• Specific work procedures, practices and requirements of the work site, including the recognition, prevention, and control of general safety and health hazards.
• Requirements of the OSHA Logging standard, Bloodborne Pathogens standard, First Aid, and CPR training.
• How to safely perform assigned work tasks, including the specific hazards associated with each task and the measures and work practices which will be used to control those hazards.
• How to safely use, operate, and maintain tools, machines and vehicles which the employee will be required to utilize in completing the assigned requirements.

 

This information is taken from one in a series of informational fact sheets highlighting OSHA programs, policies or standards. It does not impose any new compliance requirements. For a comprehensive list of compliance requirements of OSHA standards or regulations, refer to Title 29 of the Code of Federal Regulations. This information will be made available to sensory impaired individuals upon request. The voice phone is (202) 693-1999; teletypewriter (TTY) number: (877) 889-5627.