Easy Work Practice Solutions That Reduce Respirable Crystalline Silica Dust

OSHA’s new Respirable Crystalline Silica Dust Standard sets very strict standards for exposure, and contractors across the United States are developing their compliance playbook to mitigate risk. Employers must limit access to high exposure areas; provide training and respiratory protection; develop written exposure control plans; and begin to measure exposures starting in 2018.

The Nox-Crete team thinks the best way to prevent health problems related to silica dust is to avoid silica dust altogether. Several of our high-performance chemical and accessory solutions reduce the need for grinding and sanding Tilt-Up wall panels. Less grinding, less dust.

Reduce Grinding Requirements to Limit Exposure

Several products in the Nox-Crete Tilt-Up segment can be implemented as dust control work processes to meet the new OSHA requirements. First, chemically active Silcoseal cure and bondbreaker products deliver uniform and consistent panel separation. Clean panel separation with Silcoseal reduces wall panel grinding and patching requirements, thereby reducing worker exposure to silica dust.

Adding TP-Joint as a preventative work process will eliminate the traditional grinding of concrete “fins” on erected wall panel surfaces. TP-Joint is a pre-molded, flexible temporary floor joint filler that easily fits into saw cut floor/casting slab floor joints to prevent concrete seepage. Easy to install, TP-Joint is also easily removed without the use of any special tools or the need for resawing.

Better Reveals Reduce Dust

Rustication and reveal products made with wood, or porous blown PVC have a tendency to stick in Tilt-Up wall panels, which requires grinding along the entire length of each strip. Grinding, patching, sanding and sealing every inch exposes the team to unacceptable limits of silica dust.

Nox-Crete offers Clean Line Reveal, a high density extruded PVC rustication and chamfer strip. Because Clean Line Reveal won’t cause sugar retardation or expand like wood - you get a full surface contact and tighter joints that release clean from tilt-wall panels. Using Clean Line Reveal will greatly reduce the exposure to silica dust.

Use Smooth Textured Patching and Finishing Compound to Minimize Sanding

Creamy Panel Patch from Nox-Crete repairs minor surface defects on tilt-up wall surfaces, such as: air voids (bug holes), honeycombs, spalls, gouges, chips and scratches with no grinding and only minimal sanding prior to painting. With a unique blend of Portland cement, acrylic polymer modifiers and ultra-fine aggregates, high strength Panel Patch trowels out smoothly to a feather-edge thinness without any coarse, gritty feel.

Panel Patch delivers an exceptional bond to concrete and masonry surfaces, and is color-blended to match natural concrete. Because it dries in as little as 15 minutes, Panel Patch can be painted the same day.

Include Preventative Work Processes in Written Control Plans

The new rule requires employers to have a written exposure control plan that describes the following:

  • The tasks that could expose workers to silica dust
  • A description of the engineering controls, work practices, and respiratory protection used to limit exposure for each task
  • The housekeeping measures and restricted work area procedures used to limit exposure

Your written exposure control plan can also include anything else you think is important about keeping your employees safe from respirable crystalline silica at your worksite. Use Nox-Crete dust control products as a preventative work process to avoid grinding concrete.

Change is inevitable, but staying ahead of this new regulation doesn’t have to kill your profits. In fact, by taking advantage of next generation solutions from Nox-Crete, your operations can run more efficiently to give you an edge on your competition.

Key Dates For Construction Industry Compliance

  • September 23, 2017 - Comply with all obligations of the standard, except methods of sample analysis
  • June 23, 2018 - Comply with methods of sample analysis

Resources

Silica: The Nitty Gritty

  • Workers who inhale very small crystalline silica particles are at increased risk of developing silicosis, an incurable and sometimes fatal lung disease.
  • About two million construction workers are exposed to respirable crystalline silica in over 600,000 workplaces.
  • Respirable crystalline silica is a worker safety issue, which has big implications on recruiting and retaining new construction workers.

Comparing Decorative Concrete Sealer Stripper Application Methods

Nox-Crete was asked to consult on a difficult decorative concrete sealer stripper project. A 3500 square feet stamped pool deck had been sealed and resealed over time with up to five coats of an acrylic sealer with 25% solids. No stripping had been done between layers.

This thick film buildup had created an impermeable barrier that trapped water vapor coming up from the subgrade. Pressure from the water vapor caused the sealer to delaminate from the concrete, which turned some areas white in color. In addition, the thick film had suffered UV damage, and appeared dark green.

Test Methods to Strip 5 Coats of Decorative Concrete Acrylic Sealer

A test was conducted to determine the best method to remove the old coats of sealer. The test was scheduled for a clear day with a temperature of 84-degrees Fahrenheit. There was a slight 7 mph wind and 52% humidity.

Three methods were tested to remove the thick film of decorative concrete acrylic sealer:

  1. Aro-Peel stripper system with an engineered cellulose blanket was applied to a small area next to the house. Aro-Peel decorative concrete sealer stripper blanket system is sold in Canada, and a similar product—Deco-Peel—is sold in the United States.
  2. Deco-Strip sealer stripper was rolled on a large section, and then pressure washed according to use instructions.
  3. Deco-Strip sealer stripper was applied with a sprayer to another large section. The section was then scrubbed with an electric floor scrubber to loosen acrylic layers and then pressure washed according to use instructions.

Aro-Peel Decorative Concrete Sealer StripperAro-Peel Decorative Concrete Sealer Stripper Test

Aro-Peel’s controlled blanket application strips decorative surfaces of aged, chalky or faded sealers without pressure washer, accidental splatter, or the creation of hazardous waste. This is best for areas against a house where splatter can cause problems. The test area was next to the house, and was applied in direct sun in an area with little to no wind.

The surface was swept clean of debris, and the crew cut and shaped the blanket to fit the test area. The Aro-Peel was rolled onto the blanketed surface until the fabric was fully saturated and had turned translucent. Special care was taken to saturate all valleys, joints and ridges on the surface until the surface texture was visible through the fabric.

Aro-Peel Stripped 5 Layers of Decorative Sealer StripperAfter 3.5 hours, the blanket was peeled up to check for evidence of acrylic and to ensure that the surface wasn’t slimy. This is an indicator that the acrylic is still softening and has not absorbed into the blanket. Once the blanket had dried, it was peeled back and placed into garbage bags for proper disposal.

Aro-Peel successfully removed all five layers of acrylic sealer in this test. However, it must be cautioned that a second application with fresh blanket may be required to remove this many layers of sealer.

Pressure Washed Deco-Strip Test

Deco-Strip Results On 5 Layers of Decorative Concrete Sealer

A large section of the pool deck was swept clean of debris, then Deco-Strip was roll-applied and allowed ample dwell time to penetrate all the way through the acrylic sealer. Multiple light coats kept the Deco-Strip wet until the acrylic had been softened. Dwell times generally range from 30 to 90 minutes depending upon thickness of sealer to be removed and application rate of Deco-Strip. When the sealer was soft all the way through, it was time to remove with a pressure washer.

With five layers of sealer, this method was difficult. In this test, the traditional way to use Deco-Strip required a lot of water, gas for the blowers and also took a long time. If the patio had two to three light coats and was smaller—this would be an acceptable method. The test did resolve the problem, but it was decided to use another method to reduce the man hours required.

Electric Scrubber Modified Deco-Strip Test

Using a scrubbing machine to speed decorative concrete sealerA modified application test used a sprayer to apply the Deco-Strip to a large area. The Deco-Strip was allowed to sit for 3 to 5 minutes. The crew then moved the floor scrubber onto the wet product and started scrubbing in a circular direction using scrubbing pads.

The scrubbing pads were replaced every 3 to 4 minutes. To remove 5 layers of hardened acrylic, 3 pads should be used in a cycle pattern: using one, cleaning one and holding one on standby.

Once the scrubber operator and machine had moved to a new area, the previous area was lightly pressure washed to direct the stringy/sticky bubble gum-consistency old acrylic residue into a “rope” line. Larger pieces were scooped up with a shovel.

This modified method shortened the required time by 80%. The stamped concrete was successfully restored back to original unsealed condition. Natraseal LVOC acrylic sealer was used to finish the project. UV inhibitors will prevent yellowing over time, and the homeowner can expect a sealer lifetime of up to five years.

New Tilt-Up Concrete Segment Manager Tom Bozzano

Nox-Crete has brought Tom Bozzano on board as the Tilt-Up Segment Manager. Tom has over 25 years working in concrete construction as a Tilt-Up concrete Project Manager and Estimator. He has effectively negotiated with general contractors. Tom has managed construction teams to deliver projects on schedule and within budget. He is ACI Tilt-Up and Bluebeam certified.

“It’s great to bring this much hands-on field experience into the Nox-Crete team. Tom brings a practical perspective to our technical service model,” said Michael Linn, President of Nox-Crete. “Tom knows what he’s talking about. He has already given valuable insight to our Research and Development team on a new accessory line for Tilt-Up concrete construction.”

Nox-Crete Listens to Concrete Contractors for New Product Ideas

Gluing down the Clean Line Reveal

Gluing down the Clean Line Reveal

Recently, Nox-Crete has brought to market cost-saving Tilt-Up accessories that improve results. Clean Line Reveal extruded PVC rustication strips leave incredible tilt wall panel detail with limited patching requirements at a low applied cost. Nox-Crete is also launching a new precision engineered laminated veneer lumber edge form called Pac Form. Preliminary testing shows that Tilt-Up contractors can expect to get up to 20 repours with this material without warping.

 

Clean Line Reveal for Tilt-Up concrete construction

Clean Line Reveal results on unfinished wall

Tom will be responsible for bringing these new accessories to market, along with supporting the sales of the Silcoseal family of Tilt-Up concrete cures and bondbreakers.Contractors prefer Silcoseal because they get nice, clean Tilt-Up concrete panels that require very little patch or repair. Nox-Crete delivers 100% compatibility between Silcoseal bondbreaker and Nox-Crete floor hardeners to reduce risk for the project team. And Silcoseal is rain resistant, which makes it a dependable choice no matter where you are located.

He is a big baseball fan who is currently based in Las Vegas. He is excited to move his family to Omaha, Nebraska – the home of the College World Series. Tom holds an Associate Degree in Applied Science from Wyoming Tech.

Tom will participate in the Tilt-Up Concrete Association.

 

Decorative Concrete Sealer Stripper Selection Guide

Restore Decorative Concrete with Sealer StripperThe weather is warming up and it’s time to take a good look at your client’s pool deck, backyard patio, outdoor walkway or other exterior textured/stamped concrete. Is the decorative concrete acrylic sealer faded, chalky, yellowed or worn out? Don’t reapply another layer of sealer – or you’ll risk bubbling, peeling and blistering. Strip the sealer first, then apply a fresh coat of acrylic sealer for beautiful results.

Nox-Crete Sealer Strippers Are Safe and Effective

In the past, removing acrylic from concrete required the use of hazardous solvents like xylene. The solvents used in traditional strippers (xylene, toluene and mineral spirits) are considered hazardous by the EPA and OSHA. Any spent residue resulting from the use of these solvents is strictly regulated and must be disposed of through a licensed disposal facility.

Xylene is flammable, and causes skin irritation. Inhaling xylene vapor causes acute symptoms such as: headache, dizziness, nausea and vomiting. Long-term exposure may lead to headaches, irritability, depression, insomnia, agitation, extreme tiredness, tremors, impaired concentration and short-term memory loss.

Decorative Concrete Sealer StripperTo combat the use of these hazardous solvents, Nox-Crete’s chemists combine a proprietary blend of biodegradable and environmentally-friendly solvents and surfactants. Nox-Crete’s decorative concrete sealer strippers are xylene-free and safe to use. The solvents used in Nox-Crete’s decorative concrete sealer strippers are 100% biodegradable, nonhazardous by EPA definition and are safe for disposal in any storm water or sanitary sewer system.

How To Choose The Right Sealer Stripper

Decorative Concrete Sealer StripperDeco-Strip

The powerful, biodegradable coating stripper penetrates and softens decorative concrete acrylic sealers. Deco-Strip can be removed with a power washer to restore decorative concrete back to its original unsealed condition. Use a scrubbing machine to speed the stripping process of multiple layers of decorative concrete sealer.

Applications:

  • Large areas
  • When you have time to wait for concrete to dry after power washing
  • In areas where you can push acrylic residue into grass or street
  • When you need to remove multiple layers of sealers

Advantages:

  • Long working time
  • Can use scrubbing machine to speed stripping process
  • One-application to take sealers off

Tips/Tricks:

  • Acrylic resin becomes a stringy/sticky bubble gum-consistency blob during pressure-wash
  • Push the old sealer into a “rope” line in collection area
  • Shovel/scoop larger accumulations of old sealer and disposed of in trash receptacle

Deco-Peel

Deco-Peel is a two-part system, which includes 5 gallons of stripper and an engineered fabric blanket which covers 400 square feet. The blanket is cut to fit around curves, corners and hard-to-reach areas; then saturated with the stripper. The acrylic resin is absorbed and dries into the fabric blanket, which can then be peeled up and thrown away. The margin of error in application is greatly reduced with this simple system.

Applications:

  • Decorative stamped concrete areas around sensitive landscaping, sides of homes or pools that are susceptible to splatter damage
  • When it’s not expedient to use rental equipment, such as a power washer

Advantages:

  • Fast-acting – less than two hours
  • No need to wash concrete after stripping process is complete
  • Easy to use

Clean Line Reveal at World of Concrete 2017

The Nox-Crete team is on the road in 2017! Join us in South Hall booth S11439 to learn more about Clean Line Reveal - an innovative and cost effective reveal/rustication product designed to maximize the architectural aesthetics of buildings using tilt-up and/or pre-cast construction techniques.

Extruded using high density PVC, Clean Line Reveal offers the following advantages:

  • Lightweight and durable – Clean Line Reveal is a fraction of the weight of typical wood reveals and provides unique durability to construction traffic due to its composite “strut” design.  High Density PVC material and white color make it largely unaffected by climatic changes.
  • Easy Installation – Clean Line Reveal is installed using a custom formulated adhesive to maximize adhesion between a cured concrete casting slab and Clean Line Reveal.  No more time consuming drilling and fastening of wood reveals to floor slab, resulting in a floor slab requiring unsightly patchwork repairs.
  • Clean Release – Clean Line Reveals maintain their extruded dimensions, regardless of climatic conditions and remain on the floor when tilt panels are lifted, thereby eliminating costly rental equipment and “sack & patch” work to the panel face.  The more conventional wood reveals are susceptible to moisture swelling and can leach sugars aucasinosonline.com/ca/ onto the concrete panel face, resulting in discoloration of the panel face and the wood reveal “stuck in the tilt-up panel”.
  • Cost Savings – Installed cost of Clean Line Reveal provides significant cost savings by reducing labor and equipment rentals through its ease of handling, clean release, and minimization of wall and floor slab repairs.
  • Premium Architectural Aesthetics –Sharp lines from an extruded profile ensure consistency in appearance and cleanness of lines.  Multiple profiles available to satisfy your imagination.

We'll have a display of Clean Line Reveal at our World of Concrete booth. See you in Vegas!