Don’t become a statistic. The goal of this article is to help hvacr technicians avoid injury on the job.

First, let’s look at the dangers of chemicals and gases. Years ago, it was common practice to use carbon tetrachloride as a cleaning agent. This was used primarily for cleaning compressor parts during a rebuild.

You would use an open tub filled with this liquid and clean the parts using a wire brush. Most of the time, you were in an unventilated room and breathed the fumes from the tub for whatever length of time it took to do the job.

I usually left the room for a short period when my eyes became irritated and I couldn’t stand the smell. It was later found this agent causes irreparable damage to the lungs and other organs. Its use has been banned for years.

The message here is to avoid any toxic substance that replaces air in its natural form in an enclosure.

Any time it is necessary to enter a room filled with refrigerant gas, it is common practice to use an oxygen mask. This is understandable, since it would be possible to lose consciousness due to the lack of oxygen. The other reason could be more serious.

If a fire or even an electrical short in the compressor occurred, and refrigerant gas entered the area, you could be breathing phosgene gas, such as was used in World War I. This is caused by the chemical breakdown of the refrigerant. Even when soldering a joint with refrigerant gas present, deadly fumes can be produced. For the same reason, it is advisable not to smoke in a room with refrigerant gas present.


Lightning is one of the most dangerous threats to those working outside. Prior to a thunderstorm, lightning has been known to strike before the rain reaches the ground.

Any outside work required, particularly involving rooftop units, should be stopped immediately until the thunderstorm is over. There are over 50 million lightning strikes per year worldwide, as reported by the National Weather Service.


All ladder manufacturers must give the maximum weight allowed for that particular ladder and warn the user not to stand on the top rung, which is printed on the product. This pertains to “A” ladders. The biggest mistake is using a ladder that is too short for the job. Understand that, for stability, the rule of thumb is the ladder must be placed at least three feet from the building wall per 10 feet of vertical rise. Further, the base of the ladder must be level and on firm ground.

Today, the use of aluminum ladders has reduced their weight per linear foot. However, two factors must be considered:

1. Since they are lightweight, they are much more likely to fall on a windy day.

2. If the ladder touches a live electrical line, serious damage or injury can occur.

If faced with wind or nearby electrical lines, secure the ladder with braces or rope for safety. Also, wear nonskid shoes and gloves for slippery rungs. The top of the ladder should be extended four feet above the roof level for ease of dismounting and mounting the ladder. And stay in the center of the ladder to prevent it from sliding due to it not being balanced.


Scaffolds are usually used by duct and insulation technicians. A story I was told which occurred many years ago in Wilmington, DE, involved five duct installers. A scaffold was placed on the side of a building about 50 feet from the ground. Due to the height, the installers were told to rope themselves to the scaffold. Four of the men did just that.

Suddenly both supporting ropes holding the scaffold broke. Sadly, the only survivor was the unroped installer, who jumped to safety. Upon investigating the cause of the accident, it was found the total weight on the scaffold was beyond its capabilities.

In this particular case, the scaffold was supported from the roof of the building since the work was done near this location. Other tragedies have occurred on scaffolds erected from the ground due to overload and missing braces. If you work on scaffolds, be certain they are erected properly and the supporting frame is within the prescribed weight limit.


It is common in our daily work to inspect a building from top to bottom in order to properly size and install an air conditioning system. Some of the areas in

the buildings we visit have not been seen for years, and as usual in an unused area, no lighting is available.

I worked in 1963 on the Dupont Playhouse job in Wilmington, one of the oldest theaters in the country. It was erected during the Civil War, and since steel was unavailable, the whole building was constructed with concrete.

I was in the sub-basement (without light) and suddenly fell into a 31¼2 foot round hole, 15 feet deep, because my flashlight had low batteries and I didn’t see the opening.

It frightened the hell out of me, but by holding the sides with my feet and hands, I was uninjured. My hard hat, earplugs, and safety glasses, which I wore, were still on after my descent. The message here is to replace your flashlight batteries before the light gets too dim.


Back in the 40s and 50s, glass wool was the insulation primarily used in place of cork. It was lighter than cork and less expensive. I worked for Fogel Refrigerator Co. in Philadelphia, PA, and the company used this insulation in its display cases and walk-in boxes.

I was given the job of unloading boxcars of glass wool on a railroad siding in the summer sun. Due to the heat in the boxcar (120 degrees F), I decided to remove my clothing down to my pants, socks, and shoes. This was my first mistake.

My second mistake was taking a cold shower immediately after finishing my work. On my way home, I couldn’t understand why I itched so much. I had a date that night and wasn’t going to cancel it. (At 18 years of age, who would?) This was my third mistake and almost cost me my forthcoming marriage.

As you can surmise, I was covered with perspiration from head to toe. Any glass wool particles in the air cling to a wet surface. Since I took a cold shower, my body pores closed, leaving these particles protruding out like a porcupine in miniature. The end of this story is a happy marriage and three boys to prove it.

The moral: Protect yourself from airborne particles for your health and romance.


A technician doesn’t have the luxury of being distracted on the job for even one second. If you lose focus, you can lose a lot more.

The overall track record of hvacr technicians has been exemplary considering the type of work we do. So, again, don’t become a statistic. Follow the rules and arrive home whole and healthy every day.

Schaub is president of Schaub Consulting, Medford, NJ. A long-time hvacr technician, he offers additional safety tips on his website at

Publication date: 05/13/2002