Respirator Maintenance and Innovation, 2020

Wonder: What are virtues of half-facepiece reusable respirators in the current coronavirus pandemic?

This has been my usual appearance working in attics and crawl spaces. At age 75, I need the glasses for acceptable vision, and value them as protection. I have been diligent with lungs protection. There is little added effort in breathing through the respirator.

















Look inside a 3M Model 7502 half-mask respirator. Soft silicone comfortably conforms to my face. OSHA requires professional fitting, but that is simply with selection among three offered sizes, good-enough. Round silicone flappers (check valves) move inward with inhalation and close with exhalation. A rectangular flapper hinges outward with exhalation and blocks flow with inhalation. Simpler or older respirators may have a more-resistive round inhalation check at the front.

I paid $15 in 2009 for required "fitting" and OSHA training. I wear a Medium, of course. Please see much more about the fitting in a 3M training video for the less-comfortable 6000-series respirators.

We in USA are not strongly guided to protect ourselves  against coronavirus. Wear an N95 paper face mask or a surgical mask, if you think you are sick and should protect others, and if you can find one. Following mask mandates when in effect is protective of others as a matter of decency if not law. 

At March 25, 2020 I am resolved to do needful shopping and other needed self-care, always wearing my P100 respirator. I may look like a Martian, but I an doing better than those who only have access to N95 masks. I have prepared the two that I own, one new and one routinely restored as-new with careful soap-and-water scrubbing. With the second respirator, both I and my partner may escape confinement, protected.




I know that my respirators are precious. All elements are sold-out, unavailable at Amazon or anywhere else. I must preserve them, safe, for many months. Therefore with rubber bands, attach throw-away covers of facial tissue. Gain a third set of 2091 filters by putting my dirty set through a soapy wash cycle with laundry. They come out dry and with intact structure. Know then that the two new sets of 2091 filters are ample for months of usage, laundered perhaps weekly.





A small square of paper towel would be added protection of others if I got sick, but then I would just stay home.. An N95 mask or a cloth over my mouth instead of this would interfere with the respirator seal and surely is not a better idea.

Among things listed as beneficial these days, let's add frequent well-soaped laundry. Let that apply to hospitals and group homes too. I don't see the point in throw-away plastic or paper garb.

At 4/23/2020, comment upon experience with this adapted respirator. I wear this mask when grocery shopping and find the unfixed paper-towel filter of exhalation, to be unacceptable.

I have donated two 3M respirators like mine to my local fire station, in Large size purchased in erro. I want to believe more-positive protection is valued by first-responders frequently at-risk.

Read: The Real Reason to Wear a Mask, The Atlantic, April 22, 2020 
This does not conflict with my shared learning and insights.

Wear A Comfortable Respirator!

Here is a post extracted from my web site, which somehow is less discovered. I wanted it to be found with the Tools label, where labels make a blog more useful. I want to not name too many labels. That I go back and forth between a page and several blogs, tells me the future of free web sharing might be in some new venue. I think that future will be in focused book format.  Those who make the effort and earn readership will work hard. They will need small and fair compensation for their insight and work, through something like iTunes. Here is an example:

http://www.inference.phy.cam.ac.uk/sustainable/book/tex/sewtha.pdf 

This entry is prompted by dismay in following a thread at Inspection News. People working with insulation must look out for each other, not being tolerant of anything but comfortable, well-fitting,  P100 protection: oil proof, filters at least 99.97% of airborne particles. N95 throw-away covers never fit tightly, and are not acceptable.

This is the mask I use, and prefer from my own comparisons. There are many competitor products, and I will not attempt to be fair to others. This one is so comfortable, and out of the field of vision. The comfort is crucial to safety, and is worth any cost. Professional help to ensure good fit is worth any cost. I confess one reason to prefer the compact pancake filter is ability  to vacuum away too-rapid dust accumulation. I will vacuum filters several times a day when working in extreme dust, as with blowing or stirring cellulose or low-density fiberglass loose-fill insulation. That is better than choking in a cartridge mask that can not be cleared, not affording new cartridges at of the order of $10 per pair. I am thrifty, but do not begrudge the cost of frequent filter changes.

3M products are presented here. Follow manufacturer recommendations for filter renewal.

OSHA is in this conversation, with mandated worker training. I got mine in an online class purchased through my safety tools store.

At August, 2011, here is added comment. I have been making use of ideal weather, to paint another side of my house. It's sixty years old, and at thirty got painted with an early form of latex paint. All of that has to be delicately scraped off, with reveal and some disturbance of covered lead-base paint and primer. I'm removing seriously-checked soffit paint. I studiously wear this 3M respirator. Is it the right one for weatherization work, and for lead too? Here is one take on that, from PK Safety, confirming prescription of 2091 filters. 3M makes a confusing call. For various lead forms, they recommend disposable N100 respirators. There is never a call for more-expensive and better fitting P100 respirators. Surely N100 is a minimum; P100 is better.

Cutting Fiberglass Batts

Here is the best tool I have found for cutting fiberglass insulation batts:

Victorinox 12-Inch Wavy Edge BreadKnife, Rosewood Handle
by Forschner, Victorinox, Swiss Army Brands.

Use it for cutting Rockwool batts, too. They cut best with a long knife. Taping knives sold as usable with insulation batts and always inferior, are useless with Rockwool.

I found mine among quality knives at  a locksmith shop, and have used it for six years with complete satisfaction, never dulling. It is twice as hefty as my previous choice, a standard bread knife. I like to cut against decking plywood when I can, not leaving a score with the dull knife tip. I measure length or width by tape measure, always to over-fill a space. End cuts are always by eye upon measure. A length cut is often guided by some slot or by an edge over-hang. Cut full-depth without compression, or angle across the batt; an initial accurate lineup is easy to maintain.

Anyone may readily buy one from Kerekes bakedeco.com, Item 40146, at a very-fair price of $62 in March 2022. The Amazon price is  $85.


This knife will not cut cotton batts, which are best put down whole. Even a sharp hand saw struggles with batt tie threads, making a mess. The irregular cotton batts, not compressible, demand periodic fill-in with easily-cut fiberglass batts.

Basement wall insulation, to be tucked over half-buried heating ducts, is sliced with large scissors, following a drywall square.

55-Gallon Drum Liners, Again

This builds upon a post of April, 2008:
http://energyconservationhowto.blogspot.com/2008/04/distributing-or-hauling-out-loose-fill.html


They aren't just for hauling trash, and distributing insulation. Here, I needed to bag insulation, to drag it past a tight obstruction. I could drag three 24"x48" R30 batts in each transit.

Here a messy bed of R19 cellulose interfered with provision of storage in an attic. Things dropped from a deck, into loose-fill insulation, are lost. The central half of the attic floor was cleared into drum liners. Cellulose depth at the periphery would then be doubled, in an upgrade of the attic to R38, adding only batts under decks.

More area at the periphery was tossed clean of cellulose to repair deficient floor sealing, and bare areas were then refilled from the drum liners.

The air duct in the photos above is the supply to a Heatilator gas fireplace, added after house construction. The duct was thoughtlessly placed at a soffit vent, with removal of a vent baffle. With displaced cellulose, the baffle was reset, now using 2x4 blocks instead of just tapping in nails. It was interesting in this young house, to see confirmation of some of my ideas for older homes. Baffles should be plywood. Never cardboard or polystyrene. Kneewall closet walls are solidly clad outside with plywood or with OSB sheathing.

Distributing or Hauling-Out Loose-Fill Insulation

55-gallon drum liners are useful for transporting debris and loose-fill insulation in an attic. They may be collapsed as needed to pass through an opening, yet are self-supporting at a thickness of thirty mils.

There are many uses including painting or plaster prep, where major debris is collected on a sheet, and the loaded sheet is easily shaken out in the drum liner.

I buy them from:

CDF, Inc.

77 Industrial Park Rd.

Plymouth, MA 02360

1-800-443-1920

They are 30 mil thickness, Product Code 5530/34.25-G4.

I made a first purchase as a case of ten, with cost and weight breakdown thus:

Containers weighing 39.3 lb, plus box, 45 lb gross.

Charged $118.70 plus $92.91 FedEx freight, $211.61 total.

Use a drum liner too, in compressing and dragging batts through tight spaces in an attic.

Shopping Update at 7/14/2023

For delivery in Western United States, I am referred by CDF to chemicals distributor Terra Firma, of Los Angeles. 55 gallon drum liners are manufactured first for clean shipment of chemicals in 55 gallon steel drums, and Terra Firma generously sells them to permit CDF product sales with reduced shipping cost. Here is their offer to me:

CDF 55 Gal straight side 30 mil drum insert – 10 inserts per case – FOB Carson, CA

Our item # CDF552

Minimum order quantity – 1 case

1 case - $29.11/insert

2-3 cases - $26.62/insert

4 cases or more - $24.33/insert

Lead time:  3-4 days once we have your account set up, assuming we have stock available.

See cost $291.10 plus shipping in excess of $100.

Up from  $118.70 plus shipping, in 2008. That's rise of 16% per year, for fifteen years.

I will learn what is least-cost shipping with Terra Firma, probably LTL freight.

Seeking least-cost purchase, persist with direct purchase from CDF in Massachusetts. 

Unit cost is $20.6223, $206.22 for ten.

"Shipping UPS is $428.62 for 1 box. LTL rate for one box and it would run approximately $250.00."

About $456 then, direct from CDF, for a box of ten.

Here is my full CDF purchases history:

In summary and with the present opportunity, here is the drum liner cost history:

With a purchase, think to buy the dust covers at no added shipping cost.