MOPP Protection Levels

MOPP levels are something every soldier, sailor, airman, Marine, and Coast Guard member learns about as early as possible in their military Career. MOPP is an acronym that stands for Mission Oriented Protective Posture and while that doesn’t sound like much more than a standard-issue bit of military jargon, MOPP levels include potentially life-saving procedures during hostilities, national emergency, etc.

MOPP levels and MOPP gear are used when there is a threat of nuclear, chemical, or biological warfare even as an isolated attack or incident. These threats are known as NBC for short and when you hear talk of NBC threats, discussion and use of MOPP gear is not far behind.

What MOPP Is

MOPP is a bit of a catch-all phrase and can refer (generally speaking) to the current protective posture required (see below), but it can also refer to the practice of using MOPP gear and sometimes even to the gear itself.

Since this equipment and the corresponding levels of use (see below) are meant to protect against NBC threats the presence or absence of such threats is the first consideration–do troops need to wear the gear and observe the protective postures? Why or why not? These are the things commanders must contend with in the face of NBC threats.

Most learn about this during basic training where new recruits are often trained on how to quickly put on MOPP gear including protective coveralls, gloves, overboots, a hood, and a gas mask.

Some trainees have the experience of putting on all that equipment and then being marched into a “gas chamber” which is filled with tear gas. Any bad seal on a face mask or improperly worn protective gear will be obvious in this situation–no raw recruit is quite ready for what it feels like to get a whiff of tear gas.

And in some training scenarios (the author of this article personally experienced this one) you are actually required to remove your mask and state your full name before being allowed to run outside to escape the effects of the tear gas.

MOPP Gear

MOPP gear is also known as a MOPP ensemble. Basically the entire thing is an overgarment, overboots, gloves, plus the gas mask and hood designed to keep nuclear, chemical, or bacteriological agents from harming the wearer.

MOPP overgarments in the past have been manufactured with layers of activated charcoal which provides the protective aspect of the garment. Modern manufacturers have trended toward more lightweight carbon beads and more efficient garment design as a replacement for the old activated charcoal suits, which leave a distinctive black and powdery residue after wearing.

The gas mask comes equipped with removable air filters which must be changed out periodically, and the entire ensemble must be decontaminated after wearing in a real-world application. There are specific field-operational decon procedures for those who have to wear MOPP gear in an exercise or real-world event.

When Is MOPP Gear Worn?

There are a variety of scenarios where MOPP gear is worn and MOPP levels are observed. Most contemporary service members will experience this during their initial training, at their first duty assignment and beyond, and even while on deployment.

It’s true that in most American warfare during the 21st century, U.S. troops have not been attacked directly with nuclear, chemical, or biological weapons, that does NOT mean that such weapons have not been used in modern warfare.

An excellent example of this can be found in the civil war in Syria. An article published by National Public Radio (NPR) in 2019 reminds us, “Syrian President Bashar Assad’s regime carried out 98 percent” of all chemical attacks during the civil war, “…dropping chlorine gas, sarin and sulfur mustard gas on Syrian civilians.”

It’s clear from the above that chemical warfare (among others) is still a major worry when it comes to protecting troops on the battlefield.

During conflicts with terrorists, rogue states, and similar scenarios, it’s never safe to assume your enemy will abide by the Geneva Conventions, international law, etc. Chemical warfare is expressly forbidden by the Geneva Protocol which bans the deployment of “”asphyxiating, poisonous or other gases, and of all analogous liquids, materials or devices” as well as “bacteriological methods of warfare.”

But just because such warfare is a war crime, it’s never safe to assume it won’t happen on the battlefield or as part of a terror operation.

The Five MOPP Protection Levels

MOPP levels are assigned in a fashion reminiscent of the post 9/11 threat condition levels you might remember being applied in the early months following the 9/11 attacks. MOPP levels correspond both to the direct threat (or lack thereof) for an NBC attack as well as the level of protection troops need to employ to be safe from those threats.

MOPP Level 0

MOPP Zero is not indicative of “no threat at all” but rather the basic level of awareness required when operating in an environment where an enemy has, or potentially has, the ability to launch an NBC attack is possible.

At this level troops do not actually wear their protective ensemble, but must have it ready to wear at a moment’s notice. At this stage, troops must assume the gear WILL be needed, and remove contact lenses and other items that are incompatible with the protective ensemble.

MOPP 1

This threat level requires the protective overgarment to be worn, with the rest of the ensemble being carried or kept nearby for immediate use. This level indicates that either an attack could happen at any time, or when there is contamination nearby but there is no imminent threat to the troops.

MOPP 2

This is basically worn in a “yellow alert” situation (“alarm yellow” is a common identifier) where the overgarment and overboots are worn–a protective posture that assumes the rest of the protective gear will be needed without warning. MOPP 2 doesn’t necessarily indicate that an attack is imminent, but those in MOPP 2 have a much easier time getting the rest of their equipment properly donned and worn should things escalate.

MOPP 3

In situations where there is a potential hazard from vapor, contact contamination, or other issues, MOPP 3 requires the wear of all the ensemble except the gloves.

MOPP 4

This is the full protective posture requiring the wear of the entire MOPP ensemble including overgarment, overboots, mask, hood, and gloves.

These protective levels are issued by the appropriate unit, base, or theater commander and rescinded when it appears safe to do so. Those wearing MOPP equipment must pass through a “decontamination line” designed to safely process the gear and get troops into non-contaminated equipment and uniforms in a standardized way.

Joe Wallace is a 13-year veteran of the United States Air Force and a former reporter for Air Force Television News