Controlling solder fume

In a previous post I discussed the health risks associated with exposure to the fume generated during soldering with rosin cored solder. It’s a respiratory sensitiser, and is one of the main causes of occupational asthma in Great Britain. The fume is generated due to thermal degradation of the flux – usually containing colophony (alsoContinue reading “Controlling solder fume”

Partial enclosures – keeping contaminants out of the user’s breathing zone

In a previous post I discussed why captor hoods are ineffective at controlling contaminants generated by most common industrial processes. Partial enclosures, or booths, are another common type of hood which, in principle, should be more effective  for many situations. This is because they don’t have to actively capture the contaminant as it’s generated inside theContinue reading “Partial enclosures – keeping contaminants out of the user’s breathing zone”

What’s wrong with captor hoods?

Captor hoods are one of the most common types of inlet that you’ll find on extraction systems. With these hoods, the contaminant is generated and disperses outside the hood. It has to be drawn into the system by the airflow. Unfortunately, in most cases, they are largely ineffective at controlling contaminants. The following diagram illustratesContinue reading “What’s wrong with captor hoods?”


When you’ve been working in a particular profession for a while its easy to forget how confusing terminology can be. I find that although we take for granted what is meant by “local” and “general” ventilation, the meaning is not necessarily obvious to someone new to occupational hygiene or to non-specialists, such as managers andContinue reading “Jargon”

Stack Heights

When designing and testing local exhaust ventilation systems we need to pay particular attention to the design of the extraction hoods – where the contaminant enters the system. If this isn’t right then the system is unlikely to be effective at controlling contaminants. However, this doesn’t mean that we shouldn’t ensure that other aspects ofContinue reading “Stack Heights”