Industrial hygiene in Mesa: aerospace, machining and fabrication

Mesa and the East Valley are known for aerospace, machining and metal fabrication, and that work brings its own specific set of air and noise hazards, not a generic one.

Our field is industrial hygiene, the discipline behind workplace air monitoring and noise surveys.

Aerospace at Falcon Field

Boeing Mesa builds the AH-64 Apache at Falcon Field, and Boeing employs nearly 5,000 people across Arizona. Around the plant sit the suppliers that do machining, finishing and coating, which is the kind of work air monitoring and noise surveys are designed for.

Aerospace work brings a well-known set of hazards:

• Hexavalent chromium, from chromate conversion coatings and primers
• Isocyanates, from polyurethane topcoats
• Solvents, from degreasing and surface prep
• Noise, from riveting, grinding and test work

Two of these are among the easiest to sample incorrectly.

• Hexavalent chromium requires one filter type for plating and another for painting and welding.
• Isocyanates require a specially treated filter, known as a derivatizing filter.

With the wrong filter, a dirty plant gets a clean result.

→ Hexavalent chromium air sampling · Isocyanate air sampling · Aerospace plants

Metal fabrication and machining

The East Valley has many fabrication shops, and this is where we see the most common mistake in air monitoring: treating “the welders” as one similar exposure group (SEG), as if they all shared the same exposure. Welders differ in process, filler metal, how enclosed the space is, and how much of the shift they spend welding, which usually makes them three or four exposure groups.

This is also where the manganese question bites. OSHA's permissible exposure limit (PEL) for manganese is 5 milligrams per cubic meter of air (mg/m³), set in 1971. It is a ceiling limit, which must not be exceeded at any time.

ACGIH, the professional body that publishes the threshold limit values (TLVs), currently sets its TLV at 0.02 mg/m³ for the respirable fraction of the fume, the part fine enough to reach deep into the lungs.

A shop can therefore demonstrate that it meets the PEL and still be well above every current health-based limit. Measuring against both costs nothing extra, because it is the same sample.

→ Welding fume monitoring · Metal fabrication and machine shops · OSHA PELs and ACGIH TLVs compared

Practical notes for East Valley plants and shops

Most Mesa sites get their air permits from the Maricopa County Air Quality Department, not from ADEQ, the Arizona Department of Environmental Quality. We do not handle air permits, but this is a detail to get right in your register of compliance obligations.

If you file a Form R, the annual federal Toxics Release Inventory (TRI) report, Arizona requires a Toxic Data Report through myDEQ on the same July 1 deadline, plus a pollution prevention plan. myDEQ is the state's online system.

→ Arizona's pollution prevention plan and Toxic Data Report

What we do here

We work in four fields here:

• Tier II chemical inventory reporting (due March 1)
• Form R / TRI reporting (due July 1)
• Air monitoring surveys and noise surveys
• ISO consulting for environmental management (ISO 14001) and for occupational health and safety (ISO 45001)

Mesa is a short drive for us, and most projects take 1 to 3 days on site.

→ Where we work