What really happened at RIU, which led to that explosion

Last week Thursday, we got the sad news that an employee( now we hear he is the Maintenance Engineer/Manager) died and three others were injured in an explosion in the Boiler Room at RIU Montego Bay.

Since the incident, there appears to have been a news blackout and nothing appears to be coming from anyone in relation to what may have transpired.

In the absence of information, I will seek to present some likely scenarios as to what may have occurred and what could have led to this taking place.

Firstly, given the fact that the Manager was in the room at the time, one can reasonable assume there may have been a problem and he was there to assist his team in finding a solution.

What do we know

1. We know there was an explosion, but we are not sure what type
2. We know one person died and others had severe burns.

Some back ground.

A boiler is a steam generating device that produces steam at a very high pressure, depending on the use of the steam and type of boiler. Think of the Boiler being something like a  pressure cooker.

The process involves essentially heating water  in tubes( or jacket) to create superheated steam ie steam at high temperature and  pressure, which is then transferred via insulated pipes to provide hot water for laundry, steam for ironing at the laundry etc.

The process starts by what is called a purging cycle, at this stage all unburnt hydrocarbons in vapour form are removed from the burner chamber before ignition takes place. Unburnt hydrocarbons such as LPG which is used as an initiator could result in an explosion when the ignition electrodes sparks to begin the combustion  process.

The Boilers combustion controls is the device that starts the ignition process, before the fuel valve opens to allow the main fuel to enter the combustion chamber to begin combustion.

Boilers are extremely safe pieces of equipment when operated according to the recommended specifications. These equipment have a multitude of safety devices along with redundant devices and in the event one failure there is a back up. If the back up fails, it fails in what is called a “fail safe” manner, ie its failure should not result in a major catastrophic situation.

Therefore there can be namely two type of explosion

1. Fire explosion
2. Steam explosion.

The Fire explosion would most likely occur at the ignition stage which could result in the front or back door blowing off, if its is horizontal Boiler. For a Vertical Boiler depending on  the make the failure would be different.

Safety Devices for this stage

1. Boiler flame detection sensors and switches
2. Purge controls
3. High oil temp
4. High oil pressure
5. Low air pressure
6. Main flame cut out

 

Steam Explosion

For a steam explosion , there could be a number of reasons causing this namely

1. Stuck steam blow off valves ( Boilers typically has two) which must be tested daily and verified once per year ( GOJ regulations)
2. Low water alarm alarm and shutdown
3. High water level alarm and shutdown
4. etc maybe as much as 30-40 in total.

For a steam failure to occur it would be excessive pressure built up in the Boiler, which cannot escape

So for a Boiler to explode in means possible multiple safety devices failed or safety devises were bypassed ( common term is bridged out). When this occurs, the safety device no longer operates as it should, which allows an unsafe situation to continue undetected, ultimately leading to  catastrophic failure.

I hope the results of any investigation is made public, so it can assist other Maintenance Engineers in ensuring the provide their staff with sound practices to avoid any such failure in the future.

No employee should go to work and end at dead.

Bless