Chisels (Download)
Chisels Source: http://www.nytimes.com/slideshow/2008/02/19/business/businessspecial2/0219-CHISEL_8.html 1 What is a Chisel? Chisels are hand tools used to shave or chip wood, metals, concrete, and masonry. They are available for other materials as well. Most chisels are operated by striking them with a hammer, but some are simply pushed by hand . 2 What is a Chisel? Firmer chisel : has a longer blade, usually from 3 1/2″ to 6″, and is used mainly for cutting deeply into wood. It should be used with soft-faced hammers. Butt chisel : has a short blade that ranges from about 2 1/2″ to 3″ long and is for carving, paring and similar work. It can be used with hard-faced hammers. Sources: http://www.antique-used-tools.com/55chisel_2.jpg http://hand-tools.hardwarestore.com/learning/all-about-wood-chisels.aspx 3 Sources: http://www.forbes.com/2005/08/04/tools-stone-working-chisel-cx_de_0804chisel.html http://www.digitalegypt.ucl.ac.uk/tools/archive/uc63042.jpg History of Chisels “Throughout history, humans have relied on wood and stone to shelter and protect themselves, and the chisel is one of the best tools to work those materials.” “Early chisels made out of flint that date back 10,000 years have been discovered, while more modern versions are made out of tempered steel.” The ancient Egyptians used chisels to carve stone for the pyramids. 4 Typical Safety Concerns “ If a chisel is used as a screwdriver, the tip of the chisel may break and fly off, hitting the user or others nearby If a screwdriver is used as a chisel, it can slip and cause a puncture wound If a chisel is aimed toward the body when struck, it can slip and injure the user A chisel used to perform work for which it was not designed can break and injure the user Sources: http://www.osha.gov/Publications/osha3080.html http://safety.ag.utk.edu/safetyplan/17Shopweb/17shopsafety.htm 5 General Safety Concerns If chisel head is allowed to become “mushroomed,” there is a danger of metal fragments flying off If the chisel is not struck carefully with a hammer, it is possible to hit one’s hands with the hammer Fragments of the material being chiseled can fly off, creating a hazard A dull chisel is a dangerous chisel An unshielded chisel can pose a cutting hazard when not in use Sources: http://www.stanleytools.com/default.asp?TYPE=STATICLEFT&PAGE=tooltips_chisels.htm&LEFT=left_solutions.htm http://www.osh.dol.govt.nz/order/catalogue/archive/coldchisels.pdf 6 OSHA Investigated Injuries Out of 13,510 OSHA investigated deaths and injuries from 1990 to 2009, 6 incidents involved the use of chisels during the event. Of these 6: 1 death directly involved electrocution by an metal chisel, attributed to a malfunctioning extension cord. Source: Extracted from OSHA Accident Investigation Data 1990-2009 7 OSHA Investigated Injuries Out of 13,510 OSHA recorded deaths and injuries from 1990 to 2009, 6 incidents recorded the use of chisels during the event. Of these 6: 3 involved falling off a ladder while using a chisel ( 2 deaths + 1 injury ) Source: Extracted from OSHA Accident Investigation Data 1990-2009 8 OSHA Investigated Injuries Out of 13,510 OSHA recorded deaths and injuries from 1990 to 2009, 6 incidents recorded the use of chisels during the event. Of these 6: None were primarily caused by a chisel “hand tool” Source: Extracted from OSHA Accident Investigation Data 1990-2009 9 OSHA Regulations 1926.301(c) Impact tools, such as drift pins, wedges, and chisels, shall be kept free of mushroomed heads. Sources: http://images.ccohs.ca/oshanswers/g11(2).gif http://www.kleintools.com/usecarehandbook/images/pg.28-1.GIF OSHA 29 CFR 1926 Construction Industry Regulations 10 ANSI Safety Standards “All-steel chisels and punches (not wood chisels having wood or plastic handles) are subject to chipping that can cause bodily injury much the same as steel hammer faces. Therefore, applicable ANSI safety standards require the warning WEAR SAFETY GOGGLES to be on each tool.” Sources: http://hand-tools.hardwarestore.com/learning/all-about-wood-chisels.aspx http://www.raygirling.com/ryobi/images/glasses.gif 11 Safe Work Practices Always wear protective eyewear, gloves, and hearing protection Keep chisel heads free of “mushroomed” heads Always keep chisel edges sharp Use an appropriate chisel for a given task, based on the type of material being cut and the size of chisel needed Unless the material is heavy enough to withstand movement from hammer blows, it is important to clamp or otherwise secure it against movement Sources: http://www.ccohs.ca/oshanswers/safety_haz/hand_tools/chisels.html http://www.osh.dol.govt.nz/order/catalogue/archive/coldchisels.pdf http://listoftools.com/images/removing_a_rivet_head_with_a_chisel.png 12 Safe Work Practices Do not use a chisel as a pry bar or wedge Keep chisel cutting edges sheathed when not in use Never carry a chisel in pockets Always cut away from the body Never use a chisel as a screwdriver or vice versa Sources: http://www.ccohs.ca/oshanswers/safety_haz/hand_tools/chisels.html http://www.osh.dol.govt.nz/order/catalogue/archive/coldchisels.pdf http://www.gibsontimberframes.com/store/sheath3.jpg 13 Common Problem “ Accident reports have shown a pattern of injuries from the chisel. Smashed hands from missing the chisel with a hammer. Cuts from flying metal shards. Repetitive motion injuries from vibrations. Hearing loss from the high-pitched ringing of a struck tool . Source: http://www.nytimes.com/2008/02/20/business/businessspecial2/20chisel.html By adding a protective cap to the chisel’s head, the chisel is easier to strike without missing, and it prevents the head from mushrooming. The insulated handle helps dampen noise and vibration. 14 One Company’s Solution Source: http://www.nytimes.com/slideshow/2008/02/19/business/businessspecial2/0219-CHISEL_10.html 15 One Company’s Solution Source: http://www.nytimes.com/2008/02/20/business/businessspecial2/20chisel.html “…by wrapping it in a fiber-reinforced polymer sleeve that makes it safer to use and faster-cutting…” “ The cap’s larger surface and better grip gave workers the confidence to hit the bolts and rods more forcefully than they would with a standard chisel . 16 Think Safety Work Safely 17