Boiler & natural gas safety

Engineered Systems, Sept, 2004 by John R. Puskar

When it comes to boiler safety in schools and beyond, the biggest risk factors can be human, not mechanical. Starting with a tragic water heater explosion at an Oklahoma school, the article looks at how people contributed to the cause and reacted to the telltale signs of danger. Clarification of what local laws do and don't require joins a look at interlock testing to lay the groundwork for steering clear of these largely avoidable accidents in the future.

Explosions, fires, natural gas leaks, and evacuations occur somewhere almost everyday. This includes all types and sizes of educational facilities from elementary schools to universities. Here is a list of incidents from recent years.

* A boiler exploded in a Michigan junior high, evacuating over 800 students;

* The third gas leak in as many weeks caused school evacuations and concern in a Missouri community;

* A series of gas leaks were discovered on a college campus in Georgia resulting in evacuation of dorms and student centers;

* A gas leak in New Mexico hospitalized four students and one teacher during maintenance of the school's heater;

* A Houston school was evacuated after a gas leak was detected;

* A gas leak at an elementary school in Pittsburgh caused evacuation of over 400 students and fear in the community;

* A Washington, DC elementary school was evacuated due to a gas leak discovered in the school's basement; and

* An electrical fire in a boiler room at a high school in New Jersey caused evacuation of the school and injury to one person.

When disastrous events take place, human lives can be lost and property damaged. Even events that are not as devastating, such as gas leak evacuations, still result in a loss of confidence among the public, students, and parents. The entire community becomes concerned about the ongoing safety of the facility and about the capabilities of the facility's staff and administrators. In fact, a general negative perception is derived about the institution and this may take years to overcome.

In the case of property damage or injuries, some may feel betrayed since they depended on the school administrators to be fully aware of gas-fired equipment safety requirements and to check, service, and test the equipment as required by legal statutes.

The recent examples listed above are only a handful of the dangerous gas leaks and boiler-related fires and explosions throughout the United States. Boilers and hot water heaters deserve more attention and respect than they typically get. Most people do not realize that even a 100-gal residential hot water heater has the explosive force of 10 sticks of dynamite.

Every, building or facility manager somewhere is storing explosives like this at his site. The problem is that many ignore, or do not understand, the responsibility that goes with this destructive power. Sometimes the problem is a lack of knowledge, and sometimes it is a lack of emphasis. This article hopes to move you up the learning crave and not fail the people whose lives depend on you daily.

CAFETERIA TRAGEDY

We can learn a lot from a terrible elementary school hot water heater explosion that left six children and one teacher dead 20 years ago in Spencer, OK. Shedding light on the underlying causes behind the explosion at Star Elementary School provides an opportunity to review your own combustion equipment testing, repair, and PM schedules.

It was shortly after noon in the busy cafeteria. Children were seated at tables, enjoying lunch when a concrete wall, which separated the lunchroom from the kitchen, blew in. An 80-gallon water heater had exploded and launched itself skyward. The children seated nearest the wall were crushed and killed as concrete and steel were propelled from the epicenter of the blast. It was a horrific scene. In all, seven were killed and 36 lay injured.

Tragic warning signs at Star Elementary screamed out loudly to those trained to listen. Sadly, most building managers and facilities staff would never have heard them. For example, would you understand that when people complain that the water is too hot in the sinks, it could be a sign that you are about to have an explosion in your building? What about that safety relief valve that keeps dripping, or the little gas leak? It was a combination of issues as subtle as these that contributed to the death of those children and that teacher.

WHAT HAPPENED?

The first employees had arrived at the school at 7 a.m. as usual. They included the cafeteria workers, who noticed that the domestic hot water was much hotter than normal. The custodian was called and the gas water heater was shut down to await the arrival of a technician. The technician's fix was to replace the gas valve and relight the water heater. The technician returned within the hour and noted that the water heater seemed to be working normally. The cafeteria workers soon noticed that the water temperature was again much too hot, and getting hotter. They placed another call for service, which went unanswered. At 12:13 p.m. the explosion ripped through the school.