Industrial Hygiene in Construction

Sometimes the perfect storm happens and the situation seems so innocent.  Here are the variables:

• A new shop with a great ventilation system- the airflow moves from Bay 1 to Bay 5 in rapid succession
• Bays 1-4 are mechanics who occasionally work on heavy equipment/ vehicles
• Bay 5 is for welding- has local exhaust and ventilates directly outside

Situation:

• Welder usually does maintenance – small jobs
• On one particular day he is laying down A LOT of wire- and preheats the metal
• Same day- a mechanic needs to clean some parts and uses a cleaner found in most mechanic bays
• Welder “smells” something unusual- get tightness in his chest and almost passes out

What occurred was the perfect combination for a deadly situation. Chlorinated solvents, when their vapors are heated, can form phosgene.

Here is a link to the CDC regarding phosgene. Abbreviated as CG by the military- since it was used in WW1 as a weapon.

As I compiled information for a presentation titled, “Industrial Hygiene in Construction”, I wondered how to approach this topic. What I decided, is that I would start with the most frequent, the most common, with the most room for improvement. So, my list begins.

The caveat is that this list is NOT a list of the relative hazard compared to each other. This is just the IH hazards I see the most frequently. They should really NOT be compared to each other.

1. Silica – in regards to airborne overexposures and lack of controls.
2. Noise – in regards to overexposures and lack of adequate controls.
3. Lead – in regards to compliance with OSHA / EPA.
4. Asbestos – in regards to training employees and compliance with OSHA/EPA
5. Welding – in regards to overexposures and lack of controls.