Constructive Criticism

It seems Dennis Brady is now styling himself as an “expert” in ventilation.

http://www.glasscampus.com/tutorials/pdf/Ventilation.pdf

The article is fairly well written, but contains some factual errors as well as some mis-conceptions about ventilation. It’s fairly obvious that Dennis has only a bare minimum of understanding about the concepts and requirements of air movement. You also need to keep in mind that Dennis has only Canadian “experts” to call on, not American experts. Canadian standards and US standards are quite different. Take everything he says with a grain of salt.

A slightly disturbing trend

I’m concerned about some of the posts I’ve been seeing over on LE in the past few weeks. I’ve been hoping that “someone” would step in and correct some of the mis-information that is being spread, but evidently he doesn’t care enough to bother.

No room for vents??

From a post on LE:

We have lived in the same mid century (as in 1963) home for many years. My studio is not original to the house – but claimed from the overhang of the sorta second story when we enclosed the space. Two sides of the room are sliding glass doors. The opposite walls are sheet rock (my supplies) and a brick wall 2/3rds up to a window, where my workbench is located. The problem is (and I’m sure there are many more to come) is that the ceiling is is only about 7 feet. It makes for a very small space to box up all those fumes – even if I have both sets of doors open.

All the “experts” totally blew the answer to this one, mostly I think by not reading the post.

When hoods/enclosures are not possible

Several people in the past couple of days have e-mailed and PM’d me with questions about their own situations where either their significant others or landlords have not allowed them to cut holes in walls or ceilings to allow ventilation. They still want to work safely and have asked me to help them resolve this issue.

The case for studio ventilation

Many people, some of them fairly influential in the glass-working field, have publicly stated that it is difficult, if not impossible to work in a properly ventilated public studio. These same people have said that it is “OK” to open some windows and doors and use some box fans to move air around, but to also take frequent breaks. As this paper will show, this thinking is short sighted, and ultimately dangerous to the uninformed (especially new students).

This failure to take the initiative in presenting a united front for studio safety has led me to research one of the principle reasons glass-working studios MUST properly ventilate their work areas. That reason is NOx. The chief “bad actor” (as Stan Wolfersberger calls it) of the NOx family is NO2, nitrogen dioxide.

Ventilation Primer links

By popular request, I’ve added a new page that gives the links to the three articles I’ve written on ventilation. This will make it easier to look up the basic ventilation principles and formulae.