What are insulated tools and why do I need them?
Insulated tools are hand tools used by electrical workers, designed to reduce the risk of electric shock, electrocution, and arc flash. The use of insulated tools are required per OSHA and NFPA 70E standards and are a vital component of any effective electrical safety program.
Reduces does not eliminate the risk
In some situations, electrical workers will be required to work within close proximity to energized electrical circuit parts. Using safe work practices such as incorporating the use of insulated tools can reduce the risk of injury to workers and damage to equipment. Keep in mind that using insulated tools does not eliminate electrical hazards. Putting electrical equipment in a verified de-energized state referred to as an electrically safe work condition should always be the first priority.
Insulated tools are designed to reduce the risk of shock when working on or near energized electrical equipment. If a worker using a non-insulated tool contacts an energized circuit part the electricity can travel through the tool directly to the worker. Arc flashes (see figure 1) can occur when a metallic tool is dropped or inadvertently makes contact with energized circuit parts of electrical equipment. Insulated tools such as screwdrivers, Allen keys, and nut drivers reduce this risk because all but a small portion of the tool is covered with an insulating material. If they are dropped they are less likely to create electrical hazards such as short circuits.
What sets insulated tools apart from other tools
Just because a tool has a rubber or plastic handle ( see figure 2) does not make it is an insulated tool and these tools cannot be relied on for worker safety. Insulated tools must be manufactured per a standard such as the American Society of Testing and Materials F1505, or IEC 60900 Standards for Insulating and Insulated Hand Tools. Insulated hand tools should be manufactured and tested to this specification before being approved for use in your facility.
Look for markings on the tools that indicate the voltage rating and that it meets the required standard. Manufacturers are required to include the following information on each tool:
- Double triangle logo
- Voltage rating
- Manufacturer’s name
- Where the tool was made
- When it was made
- Part number
Inspect before using
Be sure to visually inspect your tools before each use. Look for cracks, nicks, cuts, or other damage to the insulating layer. Some tools incorporate a multilayer color-coded system to help identify when the tool is damaged. Obtain additional information from your tool manufacturer such as inspection and wear criteria. It is imperative to know when the tool has been compromised and should be taken out of service.
Care and Maintenance
Keep tools dry. Moisture on the surface of the tool can reduce or eliminate the insulating properties of the tool. Clean with mild cleansers like dishwashing soap. Avoid solvents that could damage insulating layers. Never toss the tools into toolboxes or bags with other sharp tools. Damage to the insulating layer can result.
When are insulated tools required to be used?
OSHA 1910.335(a)(2)(i) States: When working near exposed energized conductors or circuit parts, each employee shall use insulated tools or handling equipment if the tools or handling equipment might make contact with such conductors or parts.
NFPA 70E The Standard for Electrical Safety in the Workplace 130.7(D)(1) states that tools and handling equipment used within the restricted approach boundary shall be insulated. NFPA 70E lists the restricted approach boundary distances in table 130.4(E)(a) for alternating current systems (table 130.4(E)(b) for DC systems); see table below. Notice how the restricted approach boundary distance to 480-volts AC would be 12 inches. This means that anytime a worker’s tool comes with 12 inches of exposed energized 480-volts AC the tool would need to be insulated.
If insulated hand tools are used, are rubber insulating gloves required?
OSHA standards do not specifically require that an employee wear rubber insulating gloves when using insulated hand tools when working near exposed energized electrical conductors or circuit parts. OSHA generally leaves that decision up to the employer to determine if inadvertent contact with exposed energized conductors could be made with the hands even if using an insulated tool. For instance, could the employees hands slip off the tool and make contact causing a shock? OSHA states in a letter requesting interpretation of the OSHA electrical standards dated May 20, 1996. "Wearing rubber insulating gloves when using an insulated hand tool may be appropriate for a particular work application. For example, if an employee's hand is exposed to contact with energized parts other than the one being manipulated with the tool, rubber insulating gloves would be required". See entire letter here.
NFPA 70E guidance keeps things simple and safe
Our recommendation would be to follow the guidance provided by NFPA 70E when it comes to wearing rubber insulating gloves when using insulated hand tools. NFPA 70E 130.4(G) requires that no qualified person shall approach or take any conductive object closer to exposed energized conductors or circuit parts than restricted approach boundary set forth in table 130.4(E)(a) for alternating current systems (table 130.4(E)(b) for DC systems unless the qualified person is insulated or guarded. Rubber insulating gloves are considered insulation only with regard to to the energized parts to which the work is performed.
Notice in table 130.4(E)(a) pictured above the the restricted approach boundary distance to 480-volts AC would be 12 inches. This means that anytime a worker’s hands comes within 12 inches of exposed energized 480-volts rubber insulating gloves would be required. NFPA 70E 130.7(D)(1) states that tools and handling equipment used within the restricted approach boundary shall be insulated. Simply put, if you have a tool in your hands and you enter the restricted approach boundary the tool and hands must be insulated. As you can see by following NFPA 70E guidance the employer will be compliant with OSHA standards but more importantly employees go home safe.
Are employers required to provide insulating tools?
There isn't any OSHA standard that directly states that the employer must provide their electrical workers with insulated tools. OSHA does state that it is the employer is responsibility to make sure employees have and use safe tools and equipment and properly maintain this equipment. Although, employers are responsible for all tools, whether an employee brings his or her own tools to work or not. OSHA generally leaves the decision up to the employer to determine who provides the them this includes specialty equipment such as insulated tools.