What is Modacrylic?

Modacrylic is a synthetic fiber that is commonly used in FR-rated clothing and personal protective equipment (PPE).

Modacrylic fibers have many valuable characteristics including:

  1. Strength – It’s about twice as strong as wool, but weaker than cotton or silk.
  2. Elasticity – It has good shape retention and it’s a bit stretchable. After stretching it shows a moderate amount of recovery.
  3. Resilience – Modacrylic fiber is chemical resistant. It doesn’t wrinkle easily and retains its strength in concentrated acid/alkaline environments, which is useful for certain types of industrial filtration.
  4. Heat Conductivity – Due to its chemical composition, modacrylics are inherently flame resistant. They are poor conductors of heat, which makes them very difficult to ignite, and they will self-extinguish almost immediately.

Due to its characteristics, modacrylics are primarily used in applications where environmental resistance or flame retardancy is necessary or required. It is inherently flame resistant.

Modacrylics combine flame retardancy with a relatively low density, meaning that protective gear is not uncomfortably heavy to wear.

Modacrylic is widely used in high performance protective clothing, such as firefighting turnout gear. It is used by the most technical fabric producers, to obtain comfortable and protective blends when it comes to PPE.

Modacrylics are easy to care for and can be machine washed using warm water and tumble dried on a low setting.

What is ANSI/ISEA 138-2019?

ANSI/ISEA 138-2019 is the new standard when it comes to back-of-hand impact protection for gloves. This standard establishes the “minimum performance, classification and labeling requirements for hand protection products designed to protect the knuckles and fingers from impact forces, while performing occupational tasks.” It officially became effective in February 2019.

The current ANSI/ISEA 105-2016 standard addresses cut, abrasion, tear, and puncture resistance, along with performance. However, until now, it did it not address impact protection at all. Additionally, while the European standard EN 388 does address impact protection in a sense, it does not do so comprehensively.  

EN 388 impact standards only test the knuckles, whereas the new ISEA 138 impact standards test on both knuckles and fingers.

  • Specifically, on the thumb, index finger and ring finger, gloves are tested 25 millimeters from the top of the glove.
  • On the middle finger and the pinky, they are tested 50 millimeters from the top of the glove.

In order to achieve a level rating, all parts of the glove being tested must meet that level standard. For example, a glove meeting the Level 2 standard for the knuckles and fingers but a Level 1 standard for the thumb will only achieve a Level 1 rating.

ISEA 138 Four Key Requirements:

  1. Defining an agreed-upon testing method for a glove’s level of impact protection
  2. Includes three very clearly defined performance levels
  3. Specifies a pictogram-style marking for each of the 3 levels of compliant gloves:
  • A requirement that products be tested in a laboratory with a certificate of accreditation meeting the requirements ISO/IEC 17025:2017, General requirements for the competence of testing and calibration laboratories

The higher performance-level rating indicates a greater degree of protection, meaning that less force is transmitted through the glove to your hand.

ANSI/ISEA 105-2016 Cut Resistance Levels

Our hands are one of our most important tools, so we need to make sure that they are adequately protected.

The ANSI/ISEA 105-2016 Standard uses various testing methods on work gloves in order to determine the level of protection they will provide.

The test results are displayed on the gloves with a letter and number combination.

Here’s a chart that will hopefully help translate what those markings actually mean:

CUT LEVEL BEST SUITED FOR…
A1 Light cut hazards: material handling, small parts assembly with sharp edges, packaging, warehouse, general purpose, forestry, construction
A2 Light/medium cut hazards: material handling, small parts assembly with sharp edges, packaging, warehouse, general purpose, forestry, construction, pulp & paper, automotive assembly
A3 Light/medium cut hazards: material handling, small parts assembly with sharp edges, packaging, warehouse, general purpose, forestry, construction, pulp & paper, automotive assembly
A4 Medium cut hazards: appliance manufacturing, bottle and light glass handling, canning, drywall, electrical, carpet installation, HVAC, pulp & paper, automotive assembly, metal fabrication, metal handling, packaging, warehouse, aerospace industry, food prep/processing
A5 Medium/heavy cut hazards: appliance manufacturing, bottle and light glass handling, canning, drywall, electrical, carpet installation, HVAC, pulp & paper, automotive assembly, metal fabrication, metal handling, packaging, warehouse, aerospace industry, food prep/processing
A6 High cut hazards: metal stamping & recycling, pulp & paper (changing slitter blades), metal fabrication, automotive assembly, sharp metal stampings, glass & window manufacturing, recycling plant/sorting, HVAC, food prep/processing, meat processing, aerospace industry
A7 High cut hazards: metal stamping & recycling, pulp & paper (changing slitter blades), metal fabrication, automotive assembly, sharp metal stampings, glass & window manufacturing, recycling plant/sorting, HVAC, food prep/processing, meat processing, aerospace industry
A8 High cut hazards: metal stamping & recycling, pulp & paper (changing slitter blades), metal fabrication, automotive assembly, sharp metal stampings, glass & window manufacturing, recycling plant/sorting, HVAC, food prep/processing, meat processing, aerospace industry
A9 High cut hazards: metal stamping & recycling, pulp & paper (changing slitter blades), metal fabrication, automotive assembly, sharp metal stampings, glass & window manufacturing, recycling plant/sorting, HVAC, food prep/processing, meat processing, aerospace industry

**This is to be used as a general guideline and is for informational purposes only.**

What is a Bump Cap?

A bump cap is a type of safety PPE that provides protection for your head.

They are designed to protect you from minor head bumps and lacerations. Bump caps are worn when there is a risk of impact between your head and stationary objects such as low ceilings, and overhead piping.

Bump caps are not designed to protect your head from falling or flying objects, like a hard hat would. When there is a risk of impact with moving objects, you must use a hard hat.

When compared to hard hats, bump caps are more lightweight, generally a bit cheaper to purchase, and are easier to wear. They do not impair your vision or add height to your head.

Although bump caps are a form of personal protective equipment (PPE), they are not used for situations in which an employer is obligated to provide his/her employees with head protection for the purpose of avoiding serious injury. They are only used to provide head protection in low-risk situations to reduce exposure to lacerations, abrasions, and minor bumps to your head.

Bump caps are not appropriate for any situation in which the use of ANSI-standards-compliant head protection is required.

Remember, a bump cap is only used to protect you against contact with stationary objects, whereas a standards-compliant hard hat or other piece of recognized head-protective equipment provides protection against more significant hazards, such as the impact of a falling object that could otherwise result in a fatal injury.

What are the Features of a Surveyor’s Safety Vest?

Surveyor’s vests are designed with two main features in mind.

The first, and most important feature is visibility.

Not only do surveyors update boundary or property lines and prepare sites for construction, they also collect data relevant for the purposes of engineering and mapmaking.

Whether a surveyor is working in a busy city, or out in an open field, it’s important that they remain visible at all times.

Surveyors’ vests are made with bright neon colors and reflective, or retroreflective striping to ensure they are easily seen.

The second feature of a surveyors’ vest is functionality.

Surveyors’ vests are often equipped with pockets of various sizes, placed in optimal locations on the vest for ease of use. These include inner and outer pockets, compartmentalized pockets for writing utensils, and also very wide pockets for documentation storage.

Some vests also feature clips for lanyards or keys, and specialized pockets for cell phones, or radios.

A surveyors’ vest is not only an essential item for surveyors, they are also popular with contractors, public safety officials and anyone else who finds them useful.

What is a Safety Harness & How Does it Work?

A safety harness is an essential part of a fall protection system. It is a form of protective equipment designed to protect you from sustaining injuries during a fall.

The harness itself is an attachment between a stationary object, such as a building, and non-stationary object, such as you, the wearer. Most often harnesses are fabricated from rope, cable or webbing and locking hardware.

Most safety harnesses fit into one of the four safety equipment classes:

Class 1 – Body Belts  

Body belts are designed to be worn around your waist, like a belt. They are usually equipped with D-rings in the front or back that can be attached to a carabiner. They can also be attached to escape ropes, ladders, and other safety equipment. Although body belts are adjustable to accommodate different waist sizes, they still have their limitations. Body belts should be used for position or restraint only.

Class 2 – Seat Harnesses

A seat harness is designed to fit the body much like an actual seat would. Seat harnesses consist of a belt that goes around the waist and two smaller belts that loop around each thigh. These smaller leg belts are attached to the waist belt with straps, and each component is adjustable.

Seat harnesses keep your body in a slightly seated position, while allowing your legs to move vertically up or down a tree, pole, rock face, or other surface.

Class 3 – Full Body Harnesses

A full body harness looks much like a seat harnesses with suspenders. The harness wraps over your shoulders, around your waist, and also around your upper legs for full-body support. They are equipped with multiple D-rings, allowing them to be secured to a line at various angles. 

Full body harnesses are designed to arrest the most severe free falls. They are designed to provide the maximum amount fall protection because they offer full body support and have no risk of sliding out when being inverted.

Class 4 – Suspension Belts

Suspension belts are designed to be independent work supports, and are used to suspend a rescuer or worker. They may also be used for work seats or to raise or lower a harness.

Suspension belts are not designed to be used for fall arrest systems. They are only to be used to provide comfort and allow for long periods of suspension without the risk of cutting off circulation.

When comparing rescue and safety harnesses, make sure to get a size and weight limit that fits your body or the needs of your application. Also make sure that it fits you properly and comfortably.

How Does a Safety Harness Work?

OSHA requirements state that fall arrest systems must limit the maximum arresting force on the wearer to 1800 pounds when used with a body harness.

The harness then takes these forces and, through its system of straps and buckles, distributes them to the parts of your body best suited to absorb force and support your weight. This includes the large muscles of your upper thighs, chest and shoulders, as well as the bony mass of your pelvis. 

This also diverts the forces from the more vulnerable parts of your body like your groin, stomach and neck. 

However, the same technology used to distribute force throughout your body could cut off circulation, leading to suspension trauma.

Along with distributing force, the design of a full body harness helps to keep your body upright in a fall. The purpose of this feature is to keep your spine in a vertical position, which is the best position for it to absorb the compressive forces of a fall.  This is also the optimal position when it comes to rescuing or lowering someone to a safe location. 

NFPA® 70E – Basic Terms & Definitions

ARC Flash – An ARC flash is a fault current flowing through air between energized phase conductors, from either a phase to ground or a phase to phase fault. This results in a rapid, explosive release of radiant (90%) and convection (10%) heat energy resulting from the breakdown of air insulation into a highly conductive plasma reaching temperatures 4 times hotter than the sun (35,000 ºF).

An ARC flash can be caused by a worker moving near or coming into contact with energized conductors, which causes a spark that breaks down air insulation between conductors. Also, failure of equipment may create a spark that causes an ARC flash between energized conductors. ARC flash heat energy is measured in Joules/cm2 (J/cm2) or Calories/cm2(Cal/cm2).

ARC Rating – This is the value of energy needed to be able to pass through any particular fabric, with a 50% probability of causing a second or third degree burn. The ARC rating value is measured in calories/cm². The ARC Rating for an article of clothing is determined by a Hazard/Risk Assessment and the relevant Hazard Risk Category (HRC), and is usually measured in terms of ATPV or EBT.

Basically the ARC rating determines the protective characteristics of the fabric. The higher the ARC rating, the more protection it provides.

ATPV – The Arc Thermal Protective Value is the maximum incident heat energy that a fabric is able to absorb. This will help to lessen the severity of an injury to a 2nd degree burn. For example, if you are exposed to a potential incident heat energy level of less than 4.0 cal/cm2, the proper ATPV clothing system is 4 cal/cm2.

Calorie – The calorie is the energy required to raise one gram of water by one degree Celsius at one unit of atmospheric pressure. Second-degree burns can occur at 1.2 calories per centimeter squared per second (cal/cm²).

Flash Hazard – This is a very dangerous condition caused by the release of energy from an electric ARC.

Flash Hazard Analysis – This analysis is a study investigating the potential exposure to ARC-flash energy that may occur or be present during a specific job task. The data collected from an analysis is used for to determine safe work practices, and the appropriate FR clothing and PPE needed to prevent injuries.

Flash Protection Boundary –This is the distance from an exposed live electrical line within which a person could receive a second-degree burn if an electrical ARC were to occur.

FR (Flame Resistant) – Flame resistance refers to a material’s ability to self-extinguish upon the removal of an ignition source.

NFPA® 70E – The work standard published by the National Fire Protection Association (NFPA®) that covers all aspects of electrical safety in the workplace. This includes the necessary recommendations for adequate protection and FR clothing required for those working with, or around energized equipment.

What is HRC?

The Hazard Risk Category (HRC) is the level of ARC flash protection clothing you must wear to in order to be protected against a minimum level of incident energy that is measured in calories per centimeter squared.

In other words, electrical equipment, depending on its energy delivering capability, which can cause an explosion under fault conditions, or an ARC fault of a certain level measured in calories per centimeter squared.

That explosion can deliver a certain amount of heat to a certain distance.

Hazard Risk Category Levels

The NFPA® has identified four FR hazardous risk category levels, which are numbered by severity from 1 to 4.

Each level is considered a category, and is rated at a certain amount of flame resistance, which is also measured in cal/cm2.

HRC levels are based on specific job tasks, and are used to determine the necessary ARC rating of garments required to be worn during those tasks. You may be required to wear multiple layers of clothing in order to obtain the necessary rating required for your job.

The HRC levels range from HRC 1 (lowest risk), up to HRC 4 (highest risk).

What is NFPA® and NFPA® 2112?

The NFPA®

The National Fire Protection Association (NFPA) was established in 1896. Its primary objective is to provide education, training, and research, along with advocating consensus codes and standards in an attempt to reduce the worldwide burden of fire and other hazards on the quality of life.

The NFPA® is also the world’s leading advocate of fire prevention as well as an authoritative source on public safety. The NFPA® develops, publishes, and distributes more than 300 consensus codes and standards intended to minimize the possibility and effects of fire and other risks.

NFPA® 2112

NFPA® 2112 is the safety standard that specifies the minimum performance criteria and sets clear guidelines for the design, performance, certification requirements and test methods for Flame Resistant (FR) garments that can be used in areas where flash fires are a hazard—such as those where flammable gases, vapors, or combustible dusts might be present.

This standard calls for flash fire testing to be conducted at three second intervals with a pass/fail rate of 50% total body burn under ASTM F1930 (Standard Test Method for Evaluation of Flame Resistant Clothing for Protection Against Flash Fire Simulations Using an Instrumented Manikin) testing protocols.

What are Hard Hat Classes?

Along with different Types, hard hats also have different Classes. A hard hat’s Class indicates the level of protection it provides against electrical charges.

There are 3 Classes of protection:

Class E (20,000 volt electrical rating) hard hats reduce exposure to high voltage conductors up to 20,000 volts. These are generally used by those working in electrical trades and made from non-conductive materials.

Class G (2,200 volt electrical rating) hard hats reduce exposure to low voltage conductors up to 2,200 volts. These are commonly used in general trades and are also made from non-conductive materials.

Class C hard hats do not provide any protection against electrical conductors. These types of hard hats are considered to be conductive and have no electrical rating.

When choosing a hard hat, always make sure it is the appropriate type and class for your specific situation.

What are Hard Hat Types?

Hard hats not only come in a variety of styles and colors, but they are also classified by the Type.

It’s important to understand the different Types of hard hats, as this indicates both the type and level of impact protection it provides,

There are two Types of hard hats: Type I and Type II.

Type I

Type I hard hats are designed to protect your head from impact and penetration at the crown, or top of your head. This includes falling objects or debris that come from above and pummel the top of the hard hat.

Type II

Type II are designed not only to protect the top of your head, like Type I, but also the sides and back of your head. This includes lateral blows and impacts, as well as impacts from above.

When purchasing a new hard hat, or any PPE, always make sure it is appropriate for your environment, fits properly and is comfortable to wear.

The Magic of Kevlar®

As unimpressive as it sounds, Kevlar® is merely just a super-strong type of plastic.

Scientifically known as “poly-para-phenelyne-terephthalamide”, Kevlar® is a para-aramid fiber, and is a member of the synthetic aromatic polyamide family, similar to Nomex®.

The chemical structures of Kevlar® and Nomex® are quite similar, as they both contain many identical molecules which are tightly connected together in long ring-like chains. These run inside, and parallel to the fibers of Kevlar, similar to how rebar is positioned in reinforced concrete.

The chains are then cross-linked with hydrogen bonds in order to form long, thick fibers. This is done by forcing them through a sleeve during a very hot, concentrated state. These fibers are then woven into super stiff mats or sheets, which is what gives the material its super high-tensile strength.

Tensile strength is basically the resistance offered by a material against a force to prevent elongation.

The tensile strength of Kevlar® is about 8 times more than that of a steel wire. Surprisingly it is relatively light in weight for being so strong.

Another benefit of Kevlar® is that it has a very high resistance to both hot and cold temperatures.  It is probably one of the only ‘plastics’ that does not melt or even expand when heated, nor does it become brittle and break at very cold temperatures. Kevlar® is also highly resistant to any kind of abrasions.

Kevlar® and all of its wondrous properties were discovered in the early 1960’s by a US chemist at the DuPont™ chemical company named Stephanie Kwolek (1923-2014). She earned US Patent 3,287,323 for her invention, along with Paul Morgan, in 1966.

Kevlar®, introduced in 1971, was originally developed as a lightweight replacement for steel bracing in vehicle tires, although currently it is used in many things including gloves and even bulletproof vests.

References

Woodford, Chris. (2008/2019) Kevlar. Retrieved from https://www.explainthatstuff.com/kevlar.html. [Accessed (2019-10-26)]

DuPont de Nemous. (2019) DuPont™ Kevlar® Properties. Retrieved from https://www.dupont.com/products-and-services/fabrics-fibers-nonwovens/fibers/articles/kevlar-properties.html. [Accessed (2019-10-26)]

TeamScience ABC. [((2017-July-10) Updated (2019-Oct-19)] What is Kevlar? Why are Kevlar vests bulletproof?. Retrieved from https://www.scienceabc.com/innovation/what-is-kevlar-material-clothing-why-kevlar-armor-vests-bulletproof.html. [Accessed (2019-10-26)]