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Aug 2 15 tweets 6 min read Read on X
The air in MN right now is the equivalent of smoking a pack of cigarettes an hour thanks to Canadian wildfires.

But for less than $100, I can breathe much easier. 🧵

Here’s how a DIY Corsi-Rosenthal box can clean your air and protect your lungs. Image
First some background on why I researched and built this. Canada is burning and the AQI in Minnesota is atrocious and will continue to be for a while. This is also becoming a yearly issue where Canada bursts into flame and pollutes the entire country. Image
Today I woke up and could smell smoke and my throat hurt in spite of my home air filter on the HVAC system. I investigated my options and everything was expensive and overpromising. You realistically cannot expect 1000sqft of HEPA filtration from a device the size of a soda can. Image
Rather than spending $350+ on multiple purifiers and getting locked into proprietary HEPA filter shapes I instead looked to the COVID era. Enter the Corsi-Rosenthal box. A simple device that anyone can buy and construct with household equipment. Image
Studies have shown the boxes to reduce indoor wildfire smoke pollutant levels by at least 70%, they move large amounts of air (5 atm replacements an hour) and are suited for about 410sqft rooms. Image
The construction of a box is very simple. You need the following (per box):

4 x MERV-13 or equivalent filter (I got HDX "premium allergen" they should be of the sizes 20x20x1, 20x25x1, 20x25x2, or 20x20x2.

1 20in box fan (I used Lasko brand)

Duct tape

Cutting tool Image
Begin by forming the "cube."

Join the filters (ensuring that the air flow will match the arrow shown on the box, have the arrow point inwards) and tape them with the duct tape. Be thorough as air follows the path of least resistance like water, leave no spaces. Image
Next take the cardboard from your box fan and carefully open it up as shown. Take care to not damage the two large squares as they will both be used. Image
Take your cutting tool and cut the large panels out as shown. It doesn't need to be perfect. Image
Take your square and place it on the top of your box. This will become the bottom of the box when it's operating. Tape the square just as thoroughly as you did when joining the filters.

Tape all 4 sides. Image
Image
Flip the box over and take your fan, place the fan on top of the remaining hole and ensure it's pointed with the logo out as that way it draws air from inside the box and it flows outward.

Tape it to the box, be as thorough as you have been so far. Tape over any holes. Image
Image
Now take your last large cardboard square and draw a circle about 15 inches in diameter. Cut that circle out and affix it to the face of the fan and tape it as you have the others.

This is to increase efficiency and prevent backflow. Image
Image
Congratulations you have built your boxe(s)! You should begin to notice an improvement in air quality in the next 30 to 60 minutes if the fan is ran on high.

In total this box cost me about $80 in materials and is providing more air filtration than anything else at that price. Image
Note: place the box in the center of the room and away from walls to maximize performance
Thanks for checking this thread out! I often write about prepping and topics relating to the interest of the prepared citizen. I appreciate it if you share this with others and give me a follow!

I also have 2 books I've written if you are interested!

amazon.com/s?i=stripbooks…Image

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More from @spikesguides

Jul 27
Obstacles don’t stop you. Poor planning does.

Breaching is more than door kicking. It’s a battlefield art. Here’s how real fighters clear the way under fire.🧵 Image
Breaching and SOSRA.

Breaching, the act of creating lanes through enemy obstacles to allow assault forces to pass. In the zeitgeist breaching is just when tier 1 guys blow up doors with C2 charges but breaching is a very broad action and the drill of breaching a mined wire obstacle is actually one of the 14 primary drills taught by the US Army for infantry to be competent in the performance of. Breaching can be conducted on minefields, razor wire fields, walls and roofs of buildings, vehicle based obstacles like dragon’s teeth and tank ditches, and even the clearing of trees or crossing rivers! Breaching at its core follows the doctrinal sequence of SOSRA, where no matter what the application may be, the team can follow the steps and achieve a positive outcome when performing breaching tasks.Image
Breaching.

As previously stated, breaching is the act of clearing an enemy obstacle to create a lane of passage for assault or friendly forces to pass through safely. Breaching is often conducted under fire and almost certainly covered by enemy observation. To put it succinctly, breaching is conducted to restore mobility for friendly forces while minimizing casualties.

Doctrinally, breaches come in three forms. The deliberate breach, the hasty breach, and the in-stride breach.

The deliberate breach is a pre-planned operation and is generally very resource-heavy in nature. The team plans ahead of time where to approach a well-prepared obstacle and how to remove it. These types of breaches are used against strong defenses and obstacles that are covered by direct or indirect fire. For example, the D-Day sea wall obstacle breaches as seen in films like Saving Private Ryan depict a preplanned breach. They knew the obstacles were there, engineers brought charges, and the SOSRA sequence (which we will cover shortly) was followed.

Hasty breaches are rapidly conducted breaches when an unexpected obstacle is encountered and while contact with hostile forces has been made. Hasty breaches are used when momentum is critical and planning is not a reasonable option. Hasty breaches make use of the assets available to the team at the time. If it is an armored division they may have tank plows, if it’s an infantry team they may have to manually cut wire, whatever the situation may demand, the team employs what they have and act as fast as possible. Hasty breaches put more men at risk due to the limited planning associated with them. Examples of hasty breaches include infantry in a CQB environment blowing open a door with a shotgun or a sledgehammer, another is an infantry team cutting barbed wire that they encounter while crossing a field under fire.

An in-stride breach is performed while the team is on the move as part of an offensive maneuver, often with mechanized forces. In-stride breaches are very similar to pre-planned breaches but conducted as part of a greater maneuver and done while forces are already on the move. They are deliberate breaches but done while still on the move. This type of breach was common in soviet doctrine for decades. During Desert Storm, 1stInfantry breached Iraqi minefields with prepositioned mine clearing vehicles while the rest of the brigade flowed through behind them without a major slowdown to operational tempo. In-stride breaches are best described as “deliberate-lite.”Image
Read 6 tweets
Jun 9
He’s been watching you for hours. One shot. One kill.
You never saw him, but he saw everything.🧵

This is just one of the specialized threats modern riflemen face.

Here’s what you need to know before it’s too late. Image
Specialized Threats and Countermeasures.

“You can't say that civilization don't advance, for in every war they kill you a new way”
-Will Rogers

The postmodern battlefield is radically different from the battlefields of the Second World War or even those of the Global War on Terror. Bringing with it unique and specialized threats that riflemen should be keenly aware of in order to avoid meeting an untimely end. While a number of the threats that are encountered in the battlespace today are the same as they were 100 years ago, the tactics used by the threat actor and those countering it have changed. Snipers, IEDs, ISR assets, and landmines have all adapted to the 21stcentury in various ways while threats such as peers using NVGs and thermal observation equipment, and drones are relatively new to the western battlespace.

It should be noted that this is not a be-all-end-all guide to identify and mitigate these threats perfectly. There are entire books dedicated to each subject. The goal is to familiarize yourself with them and understand the basics of them. Not everyone is going to encounter the same threats and some may never encounter any of them. Having a basic understanding, at the very least, puts you in a space that allows you to more proactively approach situations where they may be present or react to them in a more level headed way. Every threat encountered in the battlespace is unique in it’s own way and not every strategy is perfect to engage it, use common sense and discretion in the field.Image
Snipers.

Snipers exist to operate as force multipliers, appliers of psychological pressure, disruptors of command and control, or are used for targeting and eliminating specific personnel. They are usually identified by their telltale signatures of single-round fire, precision of hits (usually to the head/vital organs), and their firing from heavy concealment followed by movement. Snipers can operate in any environment and make use of their terrain in various and unique ways.

In rural settings, snipers are more likely to engage in long-range overwatch of strategic or key areas, likely from elevated natural terrain such as ridges, treelines, and rock formations. They employ the use of natural camouflage and hand-made ghillie suits. They may have hide sites dug into the earth or concealed by foliage such as bushes.

Some potential detection cues for these snipers are unnatural terrain disruption in the area (flattened bushes, cut branches, trimmed brush), reflection or glint from sunlight hitting scopes, particularly during sunrise or sunset, local civilians may entirely avoid areas that are known sniper-dominated zones, and intermittent single-shot fire with long intervals between shots.

Potential mitigation strategies for rural area snipers are the use of terrain masking, having units move behind hills, rocks, trees, low ridges, and reverse slops to cover themselves from potential sniper fire in certain directions. Avoiding open fields and roads and making use of bounding movement is a solid way to avoid ease of detection while providing security while moving through areas that may have snipers. The use of smoke or other obscurants while crossing danger areas like roads or clear areas can make target acquisition harder. Finally the use of decoy targets such as mannequins and helmets on sticks, or use of decoy heat sources can draw fire.

Snipers operating in suburban areas will make use of abandoned homes, attics, and other multi-story buildings as hide sites. They are likely to employ shoot-and-scoot style tactics where they set up in a hide, take a few shots, and then rapidly leave the area. They may operate alone or with spotters in nearby structures or even local civilian populations. They are likely to engage in shorter distances than rural snipers but will exploit longer sightlines such as long and open roadways.

Potential detection cues include (but once again are not limited to) curtains or blinds being out of place or shifted in an unnatural manner, rooftop access doors being left open or having signs of being pried open, flat top roofs with singular bricks pushed out to create murderholes, improvised holes in fences, hedges, building walls, garages, or other areas for firing, and flash reports will be more visible at night if the sniper does not have a flash suppression device.

Suburban snipers are tricky to engage because of their shoot-and-scoot tactics. Prior to any units holding a building or ground, dismounted clear of potential sniper hides is a must. Units should avoid any obvious danger zones that funnel them into neat lines such as roads, alleyways, hedgerows, or anything of the sort. When crossing open terrain, units should use vehicle armor, hasty cover, or even soft-skinned vehicles such as civilian cars for concealment when rapidly crossing. Finally the use of thermal imaging devices will make spotting sniper threats much easier, but remember that they may also be utilizing thermal optics.

Urban sniper threats are likely to come from higher angles, that is to say, elevated terrain inside of skyscrapers and other multistory buildings, similar to that during the siege of Sarajevo. The use of pre-cut murderholes and coordination with spotters is likely to be conducted in a similar manner as suburban snipers. They are likely to use shorter engagement distances, sometimes as close as 50 meters away.

Detection of these snipers is done first and foremost from gunshots coming from rooftops or behind defilade on elevated levels of buildings. Snipers are going to leave behind murderholes that can indicate to units that a sniper has been in an area. Interrupted civilian patterns, such as avoiding streets, blocks, or even crosswalks can indicate snipers in an area. Finally the audiovisual report of their weapons may be identifiable as buildings are likely to reflect and carry more sound.

Avoiding and mitigating the threat of these snipers is similar to that of suburban snipers with the added threat of the increased height of buildings in urban centers. Roofline overwatch is a necessity when crossing in these areas and the use of the heavy corners of buildings as cover is a must. Suppressive fire on suspected positions can force snipers into cover while units cross danger areas. Finally the use of mirrors or optics on poles (including trench periscopes) to check blind spots around corners has been employed by the units such as the IDF in Israel and the Russian military in Grozny.

Some additional comments are that sniper calibers are likely to vary. Snipers in rural environments are engaging at long distances, likely with heavy duty calibers such as .338 Lapua, .300 Winchester Magnum, or even 7.62x54R. Snipers in more suburban or urban areas may use 5.56 or even as small as .22 LR caliber weapons with suppressors to hide themselves better. Snipers with thermal scopes and rangefinders are also becoming increasingly common, especially during state-backed and proxy forces as seen in Ukraine, Syria, and Israel. Civilian defenders and riflemen are likely to lack the resources for precision counter-sniper work and may more effectively focus their efforts on avoidance and detection than engagement.Image
Read 8 tweets
Jun 4
Shots ring out. Chaos erupts.

Do you immediately know who's shooting, where to move, and what to do, or are you frozen in confusion?🧵

Situational awareness isn't instinct, it's a trained skill. Here's how you stay sharp and stay alive under pressure. Image
Situational Awareness and Tactical Observation

Situational awareness and tactical observation are two skills that are critical to success in chaotic and kinetic environments. Whether conducting a security sweep in a trench or simply moving through a busy shopping mall while armed, the ability to identify cues, distinguish threats from friendlies, and when to anticipate action, are all basic skills everyone should have. By following the process of perceiving the area, comprehending it, and projecting the next moment in their mind, the warfighter, or armed citizen, is able to more appropriately approach any potential scenario, particularly using the Cooper Color Code, shifting the individual from a Condition White (completely relaxed) to a Condition Yellow (relaxed awareness).

Tactical observation is the active action of this process. Passively seeing and hearing the area is not enough, systematically sweeping areas with fixed reference points allow the individual to properly alternate between a fine and a wide focus of an area, keeping the individual well informed, propping up their situational awareness.Image
Cooper’s Color Codes.

Before delving into the concept itself of situational awareness and how to develop and train it, first the idea of Cooper’s Color Codes must be explained.

Cooper’s Color Codes are often employed by police and armed citizens to gauge how cautious or alert they should be while entering an area. The colors correspond to the severity of the situation and amount of alertness one has. The colors are:

White: Unprepared. Not looking for threats. Unready to take any action.

Yellow: Relaxed alert. No specific threat identified but prepared in case one arises. Good situational awareness.

Orange: A potential threat is identified and observed. Ready to take action. Preparing to take action.

Red: Taking action. Actively engaging the threat.

Black: Panicked, frozen, mental shock, breakdown of any type of response.

Ideally once one enters yellow, they begin employing the situational awareness levels covered later constantly and keep updating the current color code level, informing the severity of the situation and the depth of analysis needed. Someone in condition yellow probably doesn’t need to scan the area as in depth as someone who just engaged an active threat, for example. There are varying opinions on one should or should not enter condition yellow, but a good rule of thumb is if you are out of your home, condition yellow is not a bad idea. This of course is harder to apply if you are engaged in an armed conflict and you are in the field, in which case, condition yellow is a minimum when in the field. Use your head.Image
Read 12 tweets
Apr 21
You rely on your car every day—but if bullets started flying, would your ride get you and your team out alive, or get you killed? 🧵

Consumer vehicles are often adapted in survival and tactical situations. Image
In civilian life, particularly in the United States, few items are ubiquitous to almost everyone as the automobile. Used daily to get to work, home, the store, or even driven for work if you are a pizza delivery guy. In a crisis - whether it be natural disaster, civil unrest, or worse- vehicles become an invaluable asset. Vehicles are a force multiplier, without a doubt. Even without access to formal military vehicles, everyday vehicles can provide mobility, protection, and flexibility to tactical situations.Hey look it's you
Note, this is not covering traditional armored vehicles with turrets such as main battle tanks or armored personnel carriers. This is focused primarily around the use of vehicles that the average civilian has access to. This means anything in the car market, from box trucks to Nissan Altimas. Many of these concepts also apply to “motorsport” vehicles like ATVs, dirt bikes, motorcycles, even golf carts if that is the only option. On top of this, this only covers basics of the tactical usage of vehicles for foundational knowledge. Topics like CASEVAC procedures, convoy management, ambush reactions, and counter-IED tactics are extensive topics that require dedicated and in depth training and significant rehearsal. These topics are best covered individually to properly flesh them out.Image
Read 8 tweets
Mar 23
If your buddy took a GSW RIGHT NOW—could you actually keep them alive until help arrived? Or would your lack of basic combat medicine skills get them killed? 🧵

Combat medicine saves lives yet many shooters have no idea how to do it in a calm setting, much less under pressure... Image
Quick disclaimer. I AM NOT A DOCTOR. THIS IS NOT MEDICAL ADVICE. SEEK ALL MEDICAL TREATMENT FROM A PROFESSIONAL! This article provides basic educational information only and does not substitute professional medical training or advice. Always seek proper medical training from qualified instructors. The author is not liable for any actions taken based on the information provided.
Basic Combat Medicine for the Every(rifle)man

Combat medicine is a topic that is rarely discussed despite it being lifesaving at its core. It is often ignored or forgotten in favor of trusting that a medic will be nearby when the unthinkable happens. Unfortunately, that isn’t always the case and sometimes the basic actions taken by non-medical teammates can save the life of someone in dire need. Thankfully in recent years tourniquets have clamped their way down into the zeitgeist but as we’ll discuss, there are other basic measures that should be known, understood, and practiced by the average rifleman so they have the skills to save the lives of their comrades or even themselves.Image
Read 12 tweets
Mar 16
Would a well-trained militia using harassing tactics stand a chance against a conventional army?

Why or why not? 🧵

Throughout history, smaller forces have bled larger armies dry—disrupting supply lines, forcing overcommitment, and grinding them down without ever fighting head-on."Image
Harassing operations are the bread and butter of guerilla armies or for any force that benefits from utilizing small-scale attacks to disrupt hostile morale, logistics, or effectiveness in the field.

They are tools for longer-term conflicts where it may be more strategically advantageous to save manpower and focus on exhausting the enemy. The general goals of harassing operations are:

Exhaust the enemy psychologically and physically - preventing enemy forces from resting, recuperating, or generally maintain a well mental state due to a constant state of hyper arousal and worry as well as preventing them from organizing effective offensive strategies.

Force the enemy to overcommit resources towards defense – drawing resources away from the hostile force’s primary operational objectives, further wasting their resources.

Reduce their operational tempo from interference – by forcing their command structure to waste time, resources, and manpower redirecting efforts towards countering the harassing operations.

Disrupt their supply lines – logistics interdiction reduces hostile force sustainment capabilities as well as further wasting their resources.

Disruption of their communications and command structures – eliminating key positions and personnel to create disorder amongst the ranks, further hurting their collective psyche.

Impose disproportionate costs on the enemy relative to your force – self explanatory.

If we were to summarize these objectives into a single sentence it would be that it aims to “prolong the enemy’s suffering, reduce his strength over time, and prevent him from consolidating his gains,” as written by Mao Zedong in “On Guerrilla Warfare.”

But that then begs the question – what are these operations and how are they conducted?Image
As in all facets of warfare, particularly in the age of 5GW, creative and novel approaches tend to bear the greatest fruits. A successful force can take the skeleton of a strategy and adopt it to their exact scenario to fully exploit their enemy to inflict the greatest amount of damage on the hostile force. That is all flowery language to say, this list is not exhaustive and sometimes novel approaches, if well planned and coordinated, can produce equal if not better outcomes than the tried-and-true methods covered below beginning with first discussing the primary philosophy of harassment warfare, hit and run attacks.

Hit and run attacks are the backbone of harassment warfare. A topic discussed in many previous pieces (see: any guerilla tactics piece I have done). Hit and run tactics focus on engaging the enemy in very short and intense bursts of action before rapidly withdrawing and disappearing. FM 7-85, Ranger Unit Operations states: “Strike enemy forces in locations that require disproportionate responses, increasing their burden.”

The hit and run is the ethos behind all forms of harassment operations and should be the governing principal behind their planning. If a mission plan begins to involve a protracted engagement, something has gone wrong and the plan needs to be readdressed.

Common methods of harassment operations are: raids (particularly at night), indirect fire harassment, sabotage, ambushes, and targeting eliminationImage
Read 12 tweets

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