Entries tagged with “cutting”.


I was visiting a friend and in their neighborhood all of the curbs were cut for driveways (they were not poured for the cutouts). curb1

This might have saved some time for the carpenters forming & pouring the concrete. But it created additional work for the concrete cutters and the finishing of the driveways.

This lack of pre-planning created:

  • additional time to cut the curb,
  • dust (and silica, for sure),
  • the use of additional water (hopefully) to control the dust,
  • respirators (& cartridge filters),
  • exposure to noise, dust, silica

I don’t know the circumstances why this occurred, but I wonder if the person planning the development thought of the exposures to other human beings?

curb2

ps. Sorry for my blogging absence. Have been on vacation! (for some of it)

Controlling most of these types of exposures is really simple. If you know the job- and you know it will generate airborne silica = Pre Task Plan!

I wish Superintendents would enforce their project managers, or project engineers, to make a pre-task plan for every concrete/silica producing task. Then, (please don’t stop yet), review the plan once the project starts!

Below are two examples with different outcomes:wet saw

1. Cutting concrete block.

The pretask plan called for a garden hose with attachment(s) to wet the cutting area. Everything was perfect until the water was shut off. But, they improvised and found an electric water pump with bucket and recycled the water. It was a great outcome. What if the power went out? They could have used a Hudson sprayer.

2. Grinding plaster off a brick wall.

They built an enclosure and containment. They had a negative air machine with HEPA filters. They had a vacuum with HEPA filters, tyvek, 1/2 face respirator, eye protection, etc. But, as they worked the vacuum couldn’t keep up with the amount of dust generated by the 7 inch Bosch grinder. It was really dusty. They worked like this for days. No one onsite saw them because they were in containment. Unfortunately  the project is almost over and it could have been better. A simple shroud to the grinder, like this one (no endorcement) might have controlled the dust & silica. Sure, it might have been troublesome to find the exact one, and get a vacuum attachment, and have the extra weight, and ….

 

dustless shroud

So, let’s talk to people about silica, talk about solutions, and then check to see if they’re effective.