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Shop Safety

Power operated woodworking tools and machines can be  dangerous if not handled and operated properly. The following practices should be  utilized to minimize the potential for injury:

A. Personnel Training:

Only personnel who have been thoroughly trained should be authorized to operate power saws and other woodworking machinery.  Shop supervisors are responsible for constant observation of shop practices to ensure all safety regulations are being followed.  When unsafe acts are noted, it is the responsibility of the supervisor to see they are corrected.  

B. Use of Personal Protective Equipment:

Safety glasses, goggles or face shields should be worn while operating power tools.  Personnel should not wear loose clothing or other articles that may become entangled in the machine or on the stock being cut. 

C. Safe Operating Methods for Wood Saws: 

all authorized saw operators should carefully observe the following operating standards:

1. Hands should be kept out of the line of cut while stock is being fed into the saw.  
2. Stock should be held against a gauge or fence and never sawed freehand.  A push stick should always be used when short or narrow stock is being ripped. 
3. The operator should stand out of the line of the stock being cut, making sure the hands or fingers are out of the cutting area. 4. Long stock should never be crosscut on a table saw.  
4. The saw should not be left on while unattended.  
5. Sawdust and silvers should be cleaned from the saw with a brush, not with the hands or a rag.  
6. The saw guard or fence gauge should never be adjusted while the saw is operating.  
7. Saw tables 36" above the floor, offer the most efficient working height.  
8. Generally, circular saws should not be operated at speeds of more than 10, 000 peripheral feet per minute, measured at the blade. However, if blades have been tensioned for higher rates such speed is authorized.  

D. Precautions for Using Compressed Air:  

Complete safety standards for using compressed air and its generating equipment are given in Section 1.9.  The precautions set forth here pertain particularly to the use of compressed air in woodworking shops and should be strictly observed by all shop personnel: 

1. Shop personnel should not use compressed air for removing dust and wood chips from their hair, bodies or clothing.   
2. Air hoses laid across aisles, floors or doorways should be guarded by an appropriate bridge, securely fastened to the floor or properly suspended over-head to prevent tripping hazards or hose damage.  
3. Eye protection should be worn while using compressed air to clean equipment.

E. Proper Machine Locations: 

1. Circular saws should be located with sufficient space to allow free movement and easy handling of long pieces of lumber.  Minimum clearance at either end of the saw should be at least three feet more than the longest piece of stock normally used.  Long stock should be placed on either a table addition or support stands to ensure the safe operation.  
2. Circular saws should be fastened securely to floors or individual mountings.  
3. Rip saws should be so located that they will not be directly in line with other equipment.  This will prevent nearby workers from being hit by material that might kickback from the rip saw.  If space does not permit this type of positioning, a metal or plank barricade should be placed between the ripsaw and other machinery or between the saw and other personnel. 

F. Electrical switches:

Each saw should be equipped with a master switch that can be locked and tagged during repair or maintenance operations. 

1. Operating switches should be located so the operator can reach them without moving from his normal working position.  
2. Power saws should have a trip device in the switch to prevent the  machine from operating when electric service is restored after a power failure. 

G. Saw Blade Collars:

Only outer edges of collars should be allowed to bear on saw blades.  Before use, the saw should be tested for blade trueness.

H. Table Saw Feedrolls:

Feedrolls should be effectively guarded with a half cylinder blocking device to prevent the operator's hands from being caught between the rollers and stock.  A clearance of no more than 3/8” should be left between the plane of the feedrolls and the blocking device.  

I. Table Saw Power Brakes:

Each circular saw should be equipped with a power brake so the blade can be safely stopped after the motor is turned off.  

J. Floors: 

Floors around woodworking machines should be kept clean, in good repair and covered with non-slip materials as necessary.  

K. Radial Arm Saws:

1. Saws should be equipped with a mechanical device to prevent the front edge of the saw from traveling beyond the front edge of the table. 
2. A return mechanism should also be provided to automatically return the saw to the back of the table when it is released at any point in its travel. 
3. A self-locking device should be installed to keep the saw from rebounding when released.  
4. The upper hood guard should completely enclose the upper portion of the blade down to a point that includes the end of the saw arbor.  The hood should be constructed to protect the operator from flying splinters, broken saw teeth and to deflect sawdust away from the operator.  
5. The sides of the lower exposed portion of the blade should be guarded to the full diameter of the blade by a device that will automatically adjust to the thickness of the stock and remain in contact with the stock.  
6. Saws used for ripping should be provided with non-kickback fingers or dogs on both sides to oppose the thrust or tendency of the saw to pick up material and throw it back toward the operator.  They should provide adequate holding power for all the thicknesses of stock being used. 

L. Circular Saws: 

Circular saws must not be used without guards. The operator should observe the following before starting daily operations: 

1. Blades should be inspected before each use to make certain that there are no defects or cracks. 
2. Most cracks begin in teeth gullets.  If a cracked blade is used, the crack can grow larger and the blade may break.  The following precautions should be taken to prevent blades from cracking: 
   1. The blade should be tensioned for the speed at which it is to operate.  If the blade is too loose, it can vibrate, heat up, expand and crack.  
   2. The teeth should have enough clearance to prevent burning.  If the blade becomes hot, it will expand and can crack.  
   3. The saw should be perfectly rounded.  Inspect to see that the rim is concentric with the eye.  
   4. The saw should be perfectly balanced or it will wobble and can crack.  
   5. Saw blades should be kept sharp. If the blade is not cutting properly, it will pound on the wood and eventually crack.  
   6. A spreader should be used to prevent stock from kicking back.
   7. The side of the spreader facing the blade should be shaped to follow the approximate curve of the saw.  It should not be less than 3 2" wide at the tabletop.  In unusual cases where this width cannot be obtained, the spreader should be at least 2@ wide where it rests on the cutting table.  
   8. The portion of the blade below the cutting table should be completely enclosed or guarded by a rigid exhaust hood.  
    
3. Adequate supervision is necessary to ensure that guards are being used.   
4. Rip saws should be equipped with anti-kick-back dogs.  The points of the dogs should ride on the stock to keep it from being forced up and back toward the operator.  Kickbacks on ripsaws usually result from one of the following: 
   1. Failure to use a spreader.  
   2. Improperly conditioned blade, allowing stock to pinch and rise off the table. 
   3. Improperly aligned gauge or fence.  
   4. Improperly designed or mounted kickback dogs.  On a saw where the arbor is above the table, the rotation of the blade is reversed.  On this type saw it is necessary to locate the anti-kick-back fingers ahead of the blade to prevent the stock from rising.
    
5. On rabbeting and dadoing jobs, it is impossible to use a spreader.  Often it may be necessary to remove the blade hood.  This type of operation should be guarded by a jig that slides in the grooves of the transverse guide. The work should be locked in the jig and the operator's hands should be kept clear of the blade.  The standard blade hood guard should be replaced immediately after rabbeting or dadoing work is completed.  
6. All machine guards should be constructed and installed so they continue to function properly when the cutting table or blade is tilted.  
7. Push sticks should be used to prevent injury when sawing short or narrow pieces of work.  Guards should be securely in place when push sticks are used.