“Nothing is good or bad but thinking that makes it so.”
While Shakespeare was referencing something about consequence, it applies well to chemicals. No chemical is hazardous until it’s misused. So, one way to prevent misuse of a chemical is to ensure proper chemical protective clothing levels are considered for user safety. The proper protective suit ensures safety for yourself and others.
When dealing with the far-reaching range of chemicals, no one protective solution fits every situation. It’s important to understand the purpose behind each piece of gear and to get that gear from a reputable source.
Read on to learn about the impetus behind each level, how it is defined, and when it came into being.
Chemical Protective Clothing Levels by Severity
You might be tempted to work in the maximum level of protective gear. If it’s good enough for the heaviest situations, it will clearly work for the minimum situations.
Except, anyone who has worked in such gear knows that heavy gear means mobility limitations and heat. They also know that fatigue creates danger. So, be specific with your material clothing levels and do go beyond the minimum safety levels.
Materials matter in determining what chemical suit works for what level of hazard. However, material safety data sheets (SDS) don’t tend to be picky when explaining. They’ll use generic material names which make finding functional equivalents or even superior materials difficult.
Here’s a quick list of materials used and the substance they are commonly used for.
- Viton – Flexible but not too resistant to damage, resistant to aromatic and chlorinated solvents.
- SilverShield – Flexible, but easy to cut, resistant to permeation from a large variety of chemical hazards.
- Polyvinyl Chloride (PVC) – Solidly resistant to abrasion, resistant to fats, acids, and petrol hydrocarbons.
- Polyvinyl Alcohol (PVA) – Excellent impermeability to gas, chlorinated and aromatics, water-soluble.
- Nitrile – Solid chemical and abrasion resistance, a starting point for most protective gear, solid protection from oil products, caustics, and acids.
- Neoprene – Heat resistance and high tensile strength, weak to abrasion, good with acids and caustics.
- Butyl – Highest resistance to water vapors and gas, ketones and esters in particular.
With a steady 6% average growth, the chemical engineering field will continue to see developments in these materials out of necessity and breakthroughs.
One of the most important elements of chemical resistant equipment is construction. As you might imagine, open seams and loose connections defeat the purpose. Therefore, the suit design must have bound or sealed seams over the surged seam. This provides durability, strength, and protection. The prospects of abrasion and cutting to suits offer their own dangers. It’s important that materials provide visual indicators of damage.
The most flexible and earliest levels of chemical protection guidelines came from the EPA through OSHA. The levels decrease in severity starting with highly hazardous and unknown substance protection. At the low end, this covers non-hazardous substance workwear.
Representing the maximum threat from hazards, Level A requires splash resistance as well as vapor and gas-tight gear.
- Self-contained breathing apparatus (SCBA) or other positive pressure air respiration
- A fully encapsulating suit
- Chemical resistant boots, steel-toed and shanked
- Chemical resistant gloves with inner and outer layers
Level B gear depends most on chemical splash protection. Gases and vapors for skin contact are downplayed. Need for total encapsulation varies, which is one of the issues with the level system.
- SCBA or positive pressure air respiration
- Hooded resistant clothing consisting of overalls, jacket, coveralls; splash suit in one or two pieces, and disposable overalls
- Boots and gloves comply with Level A
Level C repeats most of Level B with the removal of the SCBA. Air-purifying respirators replace the positive pressure air respirator.
This level finds use when the substances in play are known and safety properties calculated. If air-purifying respirators haven’t been approved as appropriate, it remains a Level B.
This lowest level takes into account a need for protection against nuisance exposure. The environment must be considered safe without potential or actual hazards. The work uniform still requires safety features in long sleeves, protective shoes, and items such as hats or goggles.
For some, the EPA and OSHA standards levels leave too much wiggle room and come across as ill-defined. The National Fire Protection Association (NFPA) steps beyond to offer a separate set of standards. The first edition released in 2012 deals primarily with liquid solvent and splash protection. The second released in 2016 and covers vapor protection. The NFPA standards also include emergency chemical flash fire encounters. This covers both vapor and liquid protections.
The second edition NFPA 1991 issues standards for hazardous material emergencies. These are not meant to be worn long-term so comfort is less of an issue, maximizing protection.
Also as opposed to the EPA levels, NFPA provisions cover more elements. Elements such as design, labeling, testing, performance, and documentation of the gear. Vapor protection aims to protect against unknown substances and potentially known substances. These go outside of chemical concerns to include biological and radiological agents. The gear itself resembles Level A protection. However, it sets different standards for the quality of the gear as well as the durability and longevity of SCBA.
The first edition NFPA 1992 provides information on liquid splash-protection.
As with the NFPA 1991 provisions cover a variety of elements covering testing and performance. Liquid NFPA protective gear again equivocates with Level B EPA but offers more details on materials and longevity. When a garment complies with nFPA certivfication it gets a Safety Equipment INstitution (SEI) label.
No matter the hazard faced, you want to know that you use the correct chemical protective clothing levels. This ensures a smooth operation of your industry and protects the vital lifeblood of your company that is your workers.
Want detailed material information? Contact us along with further questions about the necessary safety standard.