Time to decide

It is important to note that NFPA 70E stands for minimum safe practices, not recommended procedures. Any qualified person wishing to perform a task that exposes them to electrical hazards must carry out a full risk assessment, including an assessment of the risk of electric shock and electric arcing. At first glance, this may seem confusing and contradictory. On the one hand, NFPA 70E does not mandate spark arc-resistant PPE and clothing while performing an infrared scan. On the other hand, the technician may find that PPE may be required in his or her specific case even though it is not required by NFPA 70E.

The 70E Committee considers that as long as the equipment is live, the risk of arcing remains. In Table 130.7(C)(15)(A)(a), we note that spark-arc resistant PPE may or may not be required depending on the tasks and conditions. Spark-resistant PPE may be required for personal safety even though it is not required by NFPA 70E. As mentioned earlier, 70E represents the minimum acceptable requirements and there is a possibility that these requirements may need to be exceeded. This is an example of why the user of NFPA 70E should know the entire Chapter 1 if performing tasks on electrical equipment.

There are no exceptions: ignoring the risks associated with a task under NFPA 70E will only result in you ending up in a burn centre sooner. Nobody wants to end up there. This is an area where being lazy can change the thermographer's life forever.

In addition, the person removing the enclosure must wear full spark-resistant clothing and PPE. Once the enclosure has been removed, the area secured and checked for potential hazards, the thermographer can enter and perform the scan with the PPE required for that level of risk.

Summary

Wearing spark-resistant clothing and personal protective equipment (PPE) for thermographers may now become a personal decision in some cases. Remember that OSHA requires employers to provide PPE and employees to wear such PPE if there are hazards. A hazard/risk analysis can indicate whether such PPE is necessary and this analysis should be properly recorded.

Consider the following questions when deciding whether or not to wear personal protective equipment (PPE) for thermographers:

• What would your life be like after a serious spark incident?
• What would follow for your family and friends? How would your life change if you were maimed or disabled?
• How sure are you that there are no defects in the equipment you are about to scan?

The NFPA 70E committee (and I) sincerely hope (hope) that no one ever finds themselves in a situation where they have to answer these questions because of an electrical incident. If it is really inconvenient to wear the required PPE or if there is simply no room, a viewing window can be considered.

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What are electrical parameters?

Every piece of equipment that uses or moves electricity has a set of electrical parameters. These are classifications and codes, such as CAT specifications and protection classes (IP codes), which are aligned with standards set by specially appointed teams of professionals. Understanding the electrical parameters of a device will help you better understand how to test its performance and how to keep it and yourself (and those around you) safe. Some examples of electrical parameters are impedance, inrush current, power factor and voltage drop.

What are the CAT specifications of the multimeter?

Digital multimeters are suitable for different electrical parameters, so you should check for proper CAT specifications, IP codes and independent verification symbols to ensure that the meter you select has been tested by an independent laboratory and is safe for your measurements.

When determining the correct overvoltage category (CAT II, CAT III or CAT IV) of the installation, you should always select an instrument that is suitable for the highest category in which you can potentially use the instrument and select a voltage standard that is suitable for or exceeds these situations. Meters with a CAT specification are designed to minimise the risk of an arc in the meter. Ratings are usually located near the inputs.

To give an example: if you are preparing to measure a 480-V power distribution panel, you should use a meter that is at least CAT III-600 V compliant. This means that a CAT III-1000 V or CAT IV-600 V may also be suitable in this situation.

The two-digit IP code indicates your meter's resistance to dust and water. It describes the size of dust particles that are retained and to what depth your multimeter can be submerged while continuing to function.

Degree of protection against ingress of solids

The second digit of an IP rating indicates the level of protection against water.

Degree of protection against water ingress

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At Fluke, we test our products for safety so that they go to the limit. Only when the test team is no longer able to interfere with the instrument's operation can the instrument be released for production. The goal is to ensure that a Fluke digital multimeter can withstand the most demanding real-world conditions time and time again. And that you, the user, remain safe and can return home every day. We also ensure that our products are independently tested to back up our claims.

What are security measures for multimeters?

Safe use of digital multimeters is important. Before taking a measurement with your multimeter, inspect it visually. Check the meter, measurement probes and accessories for signs of physical damage. Make sure that all plugs are tightened securely and look for exposed metal or cracks in the housing. Never use a damaged meter or damaged measuring probes.

After the visual inspection is done, check if your multimeter is working properly. Never just assume it is. Use a known voltage source or a monitoring device, such as the Fluke PRV240, to check that your meter is working properly. This is a requirement of NFPA70E (US) and GS38 (Europe).

Working with electricity always involves risk. Know what these hazards are and take appropriate precautions before you start taking measurements. Be aware of the possibility of spikes such as momentary overvoltages and arcing or sparking.

1. Always assume that any electrical component in a circuit is live until you have taken the steps to positively discharge it. Shock occurs when the human body becomes part of an electrical circuit. So pay attention to the position of your body when working in electrical environments.
2. Make sure you use the right personal protective equipment (PPE) in every situation. This means both on the body (i.e. gloves, headgear) and near the body (i.e. insulated rubber mats). These are required when working on or near live and exposed electrical circuits of more than 50V.
3. Never work alone on or near exposed and live equipment. Stay safe and make sure you and your partner are also aware of the surroundings. If possible, do not perform measurements in damp or wet environments and make sure there are no atmospheric hazards nearby (i.e. combustible dust or vapour).
4. Finally, keep an eye on the display of your digital multimeter for any visual warnings. It can alert users to irregularities such as unsafe voltages (30 V or higher) at the measurement probes.

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1. Communicate

Part of a successful business is how we communicate with each other and building a strong culture of safety. Looking at a climate of safety communication can include things like goal setting and incentive programmes. Instead of looking at accident and injury rates, Dr Pettinger suggests focusing on the positive. By focusing on accidents and injuries, “a lot of safety reporting goes underground. And it can unintentionally damage the culture.” Instead, try focusing on the quality of safety inspections or the number of employees participating in a safety initiative. In general, people are more motivated when they try to improve something, rather than avoid or reduce something (e.g. injuries).

Instead, focus on setting S.M.A.R.T. goals, which are more useful and have a positive impact on the climate of safety within the company. Dr Pettinger says: “[The goal] should be an actionable, observable behaviour that you want to reinforce, versus, for example, ‘Do your best.’ So make it specific. Make it achievable. Make it relevant to the people around you and not just you. And visualise it, make people see its importance.”

It is also important to be aware of how you talk about certain processes. This can also affect how the climate is perceived throughout the company. Dr Pettinger gave an example of how climate can affect employees negatively: “If you hear, ‘We need to get this machine running.’ There is a certain time pressure. There is a slight pressure and nobody is literally telling you ‘Skip things’, but you feel that pressure of climate compared to other cultures that say, “I don't care how long it takes. Take your time. Do it safely. Don't get hurt.”

2. Make it personal

Creating a safety plan that focuses on the individual will keep you engaged with it throughout the working day. Dr Pettinger has seen success in changing the way meetings are held at the beginning of the shift and making training more customised.

More employee engagement at the beginning of the shift has had a positive effect for many companies. Instead of just looking at what needs to be done and what the previous shift left out, Dr Pettinger recommends taking time during each meeting to discuss potential risks and how they can be mitigated. “Make sure you get those answers from the people in your group. As a good manager, it is important to let them find the solution themselves,” says Dr Pettinger.

When it comes to training and teaching, different approaches are possible. Michael Brooks, a Fluke customer, has had success with one-to-one training at his company, Great Southwestern Fire and Safety. Taking the time to go through the safety steps and ensuring that the knowledge and experience one employee has is transferred to the next. Brooks said, “What they learnt, they themselves could transfer to another new colleague. It's not the same people instructing and learning and growing all the time. We have really worked hard to maintain this positive attitude among our staff.” This has not only contributed to employee safety, but has allowed the company to grow over the years.

3. Keep building

Building a strong culture of safety does not happen overnight. Many companies fall under the so-called ‘toxic cycle’. In this cycle, new initiatives start strong, but eventually lose momentum and are completely ignored after some time. Then another new initiative is started and the cycle repeats itself. However, no real change is seen based on these initiatives and both the climate and culture of safety remain the same.

Instead, companies must find a way to achieve the “virtuous cycle”. This is all about patience and perseverance. “Culture is something that is very difficult to influence. It sometimes takes three to five or even 10 years to change,” Dr Pettinger said.

Once a new initiative has started, set short-term goals to make it feel more like progress is being made. Not only will individual employees feel they can be more influential, but management can also keep track of what changes have been initiated. Once people see the value of the new process, it will become self-perpetuating, ingrained and help your organisation create a culture of safety.

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Myth 2: The more personal protective equipment, the better

Whether to wear personal protective equipment, and how much, is not a matter of personal choice. A component can fail at any time. Perfectly working circuit breakers can suddenly malfunction while troubleshooting. If an arc occurs just by opening a cabinet, wearing the right personal protective equipment can mean the difference between life and death. Electricians and technicians should follow the detailed personal protective equipment requirements in European standard EN 50110 “Operation of electrical installations”, which defines electrical safety in the workplace. However, requiring workers to wear personal protective equipment classified for a much higher risk level than required by the environment does not necessarily make them better protected.

“More personal protective equipment is not necessarily better,” says Kevin Taulbee, Electrical Engineer and Safety Trainer at Power Studies, Inc. “It's all about using the right personal protective equipment. Doing a proper hazard analysis before the job is important to equip employees with the right PPE. Too many people just buy arc-resistant moon suits and thick high-voltage gloves for cable workers for their in-house maintenance workers and electricians. Class 2 electrical gloves are not necessary if they never come into contact with a voltage of more than 480 V, and they offer much less freedom of movement. As a result, an electrician is more likely to drop tools or test leads when working on a live panel.”

In addition to choosing the right PPE, it is possible to choose hand tools designed to make it easier to operate buttons and dials when heavy gloves are worn. It is also possible to reduce the number of personal protective equipment required in some cases by equipping workers with non-contact infrared instruments (IR instruments), such as thermal imaging cameras, infrared thermometers and wireless monitoring sensors. These tools allow workers to capture data from outside the arc zone. Removing the need to work within an arc boundary, especially when switching or troubleshooting, increases the overall level of safety for workers.

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Myth 3: All test leads and fuses are the same

Often technicians consider test leads and fuses as basic components without paying much attention to quality. Regardless of the quality of the multimeter, it is only as safe as the test leads used and the fuses inside. These components provide essential protection against current and voltage spikes that can cause serious injury to the user.

Choosing the right test leads

The main task of test leads is to connect the digital multimeter to the device to be tested, but they are also a first line of defence against electrocution. Measurement leads that are poorly made, worn out or not suitable for the work to be performed can produce inaccurate readings and pose a serious shock hazard if touched with the wrong wire. When choosing measurement leads, pay attention to the following:

• High-quality materials and robust construction
• Classification for the relevant measurement category as specified in EN 61010 and the voltage level of the application. The category (CAT) of the measuring leads and accessories must match or exceed the category of the DMM.
• Exposed metal corresponding to the energy potential of a specific measurement.
• Retractable measuring pins, measuring pin sleeves or measuring pins with shorter ends to prevent accidental short circuits.

Choose high-quality replacement fuses

Current safety standards require that digital multimeters are equipped with special high-power fuses designed to keep the energy generated by an electrical short circuit within the fuse housing. This protects the user from electric shock and burns. When it is time to replace fuses, always choose high-power fuses approved by the meter manufacturer. Cheaper generic replacement fuses increase the risk of serious injury.

Myth 4: The only way to accurately measure voltage is to make contact with a test lead.

In the past, connecting test lead probes or crocodile clips directly to electrical conductors was the best way to obtain accurate results. However, this requires metal-to-metal contact, which increases the risk of arcing and possible injury to the person measuring or damage to the equipment being measured.

Recently, a novel technology introduced that detects and measures voltage without metal-to-metal contact. This technology isolates the measuring instrument from the voltage source under test. To measure voltage, electricians and technicians slide only one conductive wire into the open fork of the hand-held measuring instrument. Because they are not exposed to live contact points, there is less risk of electric shock and arcing.

The myths mentioned above are just a small selection of the safety issues that should be considered when working on live equipment. The best way for a facility to ensure that employees fully understand and comply with all relevant electrical safety regulations is to develop and maintain a solid safety culture based on the needs and environment of that particular facility.

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Anyone who makes a living working with electricity soon develops a healthy respect for anything that could be even remotely live. Yet time constraints and stress due to the critical nature of the equipment can lead to carelessness and uncharacteristic mistakes even in the most experienced electrician. The list below provides a quick overview of what not to do when measuring electricity.

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1. Replacing the original fuse with a cheaper one. If your digital multimeter meets current safety standards, that fuse is a special sand-filled fuse that will burn out before an overload can reach your hand. If you change the fuse on your DMM swapped, always replace it with a fuse approved for the instrument.
2. Use a piece of wire or metal to bridge the complete fuse. This may seem like a quick fix for when you unexpectedly do not have a spare fuse with you, but that fuse is the only thing separating you from the voltage spike coming your way.
3. Using the wrong tool for the specific job. It is important that your DMM is suitable for the work you will be performing. Always ensure that your measuring instrument has the correct safety specification for the work you are doing, even if this means changing DMMs throughout the day.
4. The cheapest DMM choose. You can always switch to a more expensive model later, right? Maybe not, either, if you become the victim of an accident. This is because the cheap measuring instrument did not have the safety features indicated. Always look for statements from independent testing laboratories.
5. Leaving your safety glasses in your breast pocket. Get those glasses. Put them on. It's really important. The same goes for insulating gloves and flame-resistant clothing.
6. Working on a live circuit. If at all possible, de-energise the circuit. If you do have to work on a live circuit, use properly insulating instruments, wear safety goggles or face shield; and insulating gloves, remove watches and jewellery, stand on an insulating mat and wear flame-resistant clothing instead of ordinary work clothes.
7. Failure to provide proper safeguards and texts against reactivation of the installation.
8. Use both hands when measuring. Do not do this! When working on live circuits, use the following trick: Keep one hand in your pocket. This reduces the risk of a closed circuit through your chest and heart. Hang the measuring instrument if possible, or place it somewhere. Touch the instrument with your hands as little as possible to minimise exposure to the effects of transients.
9. Neglecting your test leads. Measurement leads are important for the safety of the DMM. Make sure your measurement leads also have the right safety specification for the work you are doing. Preferably use measurement leads with double insulation, insulated input connectors, finger protection and non-slip surface.
10. Keep using your old measuring instrument. Today's measuring instruments have safety features no one had heard of a few years ago; features that are worth modernising your equipment and are a lot cheaper than a visit to the emergency room.

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