Choosing Safer Hand Tools
You may not give much thought to the handles on your hand tools, but you should. They are the only physical connection between you and your tools.
You may work with these tools for six or more hours in a normal work day. Using the right size handle can reduce fatigue and increase productivity, improve the quality of your work, and reduce the risk for hand and wrist problems. Awkward wrist positions can lead to repetitive strain injuries and reduce your grip strength. You can injure your hand, wrist, or arm, leading to carpal tunnel syndrome, trigger finger, white finger, and other painful problems. You can do this if you must hold a tool tightly for a long period of time or keep twisting the handle. Handles and handle areas that allow you to work with your hand and wrist in a comfortable position with your wrist straight and/or that limit the time you work with your wrist bent or twisted are best.
Tools that say they are “ergonomic” or “ergonomically designed” may have some very good features, but just having that label doesn’t mean the tool is safer for YOU. A tool is only “ergonomic” if it fits YOUR hand and is right for the work you are performing. The following sections provide detailed information on what you should consider when choosing safer hand tools.
What is my hand size?
Everyone is different, but there are some key measurements that will help you select hand tools that are the right size for you. You will need to know your hand (length), grip and palm size. Some people may be able to gauge these measurements by just looking at their hand in relation to a tool. Others prefer to use precise measurements.
A person’s hand size is measured by the length of their hand. To figure out the length of your hand, measure the distance from the fold in your wrist below the palm to the tip of your middle finger when your hand is flat. The widest part of your palm is your palm size.
There are a few ways to find your grip size:
1. Experiment. Take a tool you already own that has a handle that feels too small and put a few wraps of duct tape around the handle in the place where you hold it the most. Use the tool for a day. Keep adding tape until it starts to feel too large, and then remove a few wraps until it is comfortable. Wrap a tape measure around the area that you’ve taped to find the grip size that works the best for you.
2. Measure your hand’s grip diameter and use it to calculate your grip size. Use your hand size. 20% of your hand length equals your grip diameter. EXAMPLE: 20% of a 7-1/4″ (or 7.25″) hand length equals about 1-1/2″ (calculated as follows: 7.25″ x 0.20 = 1.45″ –rounds up to 1.5″)
Use the “OK” test. Make the okay sign using your thumb and index finger and then measure the inside of the “O” formed to find the diameter. In photo 2, for example, the hand diameter is about 1-1/2″ (or 1.5″).
Once you know your hand’s grip diameter, you can calculate your grip size by multiplying your grip diameter by 3.14. EXAMPLE: A hand with a grip diameter of 1-1/2″ (or 1.5″) would have a grip size of roughly 4-3/4″ (calculated as follows: 1.5″ x 3.14 = 4.7″).
3. Rely on the research. The National Institute for Occupational Safety and Health (NIOSH) suggests a grip diameter range of between 1-1/4″ to 2″. These measures are equal to grip sizes of roughly 3.9″ to 6.3″ for a “power grip.” If the length of your hand is on the larger size, go for the higher grip size. If the length of your hand is on the smaller size, go with a lower grip size.
Your grip span is the distance between the thumb and fingers when the tool jaws are open or closed.
To calculate your strongest grip span, measure your hand while spread wide open from the tip of your thumb to the tip of your little finger in centimeters (cm), divide that number by 5, and add 1.5 cm. For example, if your open hand size from the tip of the little finger to the tip of the thumb is 18 cm, then your strongest grip would be about 5.1 cm or 2″ (Calculation: 18 cm divided by 5 = or 3.6 cm; 3.6 cm + 1.5 cm = 5.1 cm or about 2″. (This online Metric Conversion calculator easily converts centimeters to inches.)
Use your hand size when purchasing hand tools
The most important thing to keep in mind when choosing safer hand tools is to find a tool that feels comfortable in your hand and is right for the work you are doing. Using a hand tool with a grip size that is too big or too small for your hand will increase the force you need to apply when using the tool, the amount of work your hand has to do, and the risk for injury.
A hand tool with a grip size that is the same or close to your hand’s grip size will allow you to work with the maximum grip strength, result in less fatigue when you use the tool for long periods, with a lot of repetition or with weight added, and reduce your risk for injury.
What to look for when choosing safer hand tools
What should have the greatest influence over your purchasing decisions?
- Believe it is important to purchase hand tools that reduce the risk of injury
- Comfort, durability, and familiarity have the greatest influence when purchasing hand tools
- Take steps to ensure your hand tools “fit your hand better,” by grinding, sanding, shortening or extending handles, adding grips, or changing the handle size.
Hand Tool Examples
There are specific hand tool measures and features to consider when deciding if a hand tool is right – ergonomic – for you. But often, those measures are not readily available on manufacturers’ websites or packaging materials.
The following provides these measures and features for examples* of different types of hand tools. This information can be used as a point of reference when comparing and purchasing hand tools. The models and brands included were identified through a survey of masonry craft workers and discussions with instructors.
The Learn More section includes links to manufacturers and sources identified through surveys and discussions, as well as other resources to help you identify and select “ergonomic” hand tools.
The following are links to examples* of manufacturers and distributors of hand tools. Take advantage of the Contact features on their websites to ask for the measurements you’ll need to make informed decisions when purchasing hand tools.
- Visit or Contact BAC Tool Sales
- Visit Bon Tool or Contact Bon Tool
- Visit Estwing or Contact Estwing
- Visit Hubbard Jointers or Contact Hubbard
- Visit Kraft – (Rose Trowels & Superior) or Contact Kraft
- Visit Marshalltown or Contact Marshalltown
- Visit Stanley or Contact Stanley
- Visit Vaughan or Contact Vaughan
- “Easy Ergonomics: A Guide to Selecting Non-Powered Hand Tools” – CAL/OSHA, NIOSH and CDC
- “Are hand tools ergonomically designed?” – Canadian Centre for Occupational Health and Safety
- “What to look for when selecting or modifying hand tools to provide a better fit with the user” – Agrability Project
- “Ergonomics Demonstration Project (Update) Masonry Industry” – Washington State Department of Labor and Industries