By: Maureen Paraventi
Knives have been used by humans for approximately 2.5 million years1. The modern safety knife has its origins in ones made of flint dating back to the Prehistoric Period and can be used to cut strapping and cable, open boxes and bags, puncture shrink wrap and for many other tasks. It is a ubiquitous, deceptively simple tool that has been developed to help make workplaces safer.
Laceration injuries can be costly
Cuts and lacerations caused by cutting tools that do not have features – like self-retracting blades – account for approximately 30% of all workplace injuries. Even minor cuts require first aid. Deep lacerations need some form of medical treatment – like sutures – and can result in nerve or tendon damage. According to OSHA, each occupational laceration injury costs an average of $21,872 in direct costs, with another $24,059 in indirect costs2. Ergonomic injuries which occur over long-term use can also be costly. Both types of injuries may result in days away from work, which affects productivity and may disrupt workplace operations.
Causes of injuries related to knife use
A knife in poor condition. An easily overlooked cause of knife-related injuries is a dull blade, which will force the user to exert greater force in order to cut the material. This increases the likelihood that the knife will slip and cause a laceration or puncture wound to a hand, arm or leg. Some blades on non-safety knives are designed to snap off when they become dull, but that in itself could be a hazard. Using a dull knife for repetitive motions will increase the likelihood of joint and nerve pain and can even lead to a permanent crippling injury to hands, arms or the back. Employers should have a specific knife sharpening program with clear procedures and should provide workers with adequate opportunity to sharpen their knives or obtain a sharpened knife at all times. With fixed-blade and/or retractable knives, it’s important to make sure the blades are securely seated and free from nicks or chips.
Lack of personal protective equipment (PPE). Certain tasks require the use of puncture-resistant gloves. The employer should provide this type of hand protection to employees who perform high-risk activities, and ensure that the gloves fit them correctly. Additionally, safety eyewear will protect the worker in the event of a blade breaking.
Using a poorly designed knife. Ergonomic injuries to the muscles, tendons and nerves of the hand related to knife use are primarily due to repetitive motions. The best way to avoid repetitive stress injuries is to choose safety knives, which have handles specifically designed for ergonomic safety.
To prevent cuts when using hand tools with sharp blades3:
- Use the right tool for the job.
- Only use the tool only for the job it was designed for. For example, a knife should not be used as a pry bar, can opener, chisel, punch, awl, scraper or screwdriver.
- Educate and train all staff in the safe use of any tool they may use.
- Inspect the tool before use.
- Make sure the blade is sharp. Dull blades require more force, increasing the chance of injury.
- Carry one tool at a time, with tip and blade pointed down at your side.
- Work in a well-lit space so you can see what you are doing.
- Cut on a stable surface. Use a cutting board and/or slip-resistant matting to prevent the item from sliding on the counter.
- Where possible, use a mechanical device to hold the item.
- Hold the tool with your stronger hand.
- Use protective clothing such as cut resistant or mesh gloves, especially for the holding hand. Safety glasses will protect the eyes if the blade shatters or breaks.
The right way to change blades
Using a knife to cut something is not the only time an injury can occur. Changing a blade is also potentially hazardous. Here are guidelines intended to minimize the risk of injury when changing fixed-blade knives or retractable-blade knives:
- If you need to use a screwdriver to open the knife, lay the knife on a flat surface rather than holding it in your hand.
- When you insert the new blade, make sure that it is seated properly and securely.
- After replacing the screw, test the knife to confirm that it has been properly reassembled.
- Dispose of the used blade right away, preferably in a blade disposal box.
Using high-quality safety knives, having a blade changing program and training workers to use knives properly will go a long way toward preventing injuries. WMHS