Why are explosives dangerous

The change of state occurs almost instantaneously — thus there is a rapid increase in volume as solid converts to gas, and a further expansion because the change is accompanied by a large release of chemical energy in the form of heat — up to several thousand degrees. It is this rapid and dramatic increase in volume that produces the desired physical effect. In the case of high explosives, the effect is to shatter and destroy anything nearby, and in the case of low explosives, to produce a massive kinetic force.

The energy release is the same, but in the case of low explosives, the molecules are designed to change fractionally slower, to produce a powerful shove, rather than a rapid slash. Although explosives can behave in a violent way when suitably initiated, they are designed to be quite stable and insensitive under normal surface conditions. This means that they can be handled and transported by land and sea quite safely, so long as they are not subjected to violent shock, as in a high-speed traffic accident, or worse, allowed to get hot in a fire.

There are 6 divisions in Class 1, the divisions show how the explosives will react and behave when initiated. The items are also assigned one of 13 Compatibility Group letters, basically to indicate which types may travel safely with which. Explosives are declared as NEQ Net Explosive Quantity when described in the transport document, separate to the gross weight.

Our experts are ready to help. It is strongly recommended that a departmental dangerous substance inventory is kept and maintained detailing the substances and where they are stored. Carry out a risk assessment and record it. This is a careful examination of the dangerous substance hazards you use and store at work, and the likelihood of creating a explosive atmosphere, potential ignition sources and the expected consequences and who could be harmed.

Further advice on risk assessing dangerous substances can be found in the resources section. Advice is also available from Health and Safety Advisory Service. Put in place control measures to either remove or, where this isn't possible, control the risks. This will be the arrangements to reduce the likelihood of an explosion and the consequences if it does, including emergency arrangements. Schedule 1 General safety measures. Provide information, instruction and training for employees and others to control or deal with the risk.

Identify and classify areas of the workplace where explosive atmosphere may occur and avoid ignition sources in those areas. For more information on zoning and ignition sources go to hazardous area classification and control of ignition sources. Student Directory. Services and facilities Advice and support Accommodation Buildings, grounds and maintenance Careers services Childcare Design, print and copy services Events, meetings and conferences Food and drink IT services Learn a language Library services Post and property services Professional Services teams Sport Theatre and arts Travel and transport.

Our University Equality, diversity and inclusion Freedom of information Sustainability and biodiversity Brexit advice and support. Online services. Support and Contact. Examples found at work include: solvents paints and varnishes flammable gases liquid petroleum gas LPG dusts from machining and sanding operations dusts from food stuffs pressurised gases substances corrosive to metal The Health and Safety Executive have a wide range of up-to-date information and resources to help you decide if a substance is dangerous: Dangerous substances HSE resources on dangerous substances Requirements The University must prevent or reduce the risk from dangerous substances.

Identify dangerous substances Find out what dangerous substances you have and the fire and explosion risk. Risk assessment Carry out a risk assessment and record it. Control measures Put in place control measures to either remove or, where this isn't possible, control the risks.

Training Provide information, instruction and training for employees and others to control or deal with the risk. Zoning and ignition sources Identify and classify areas of the workplace where explosive atmosphere may occur and avoid ignition sources in those areas. Further information and resources. HSE guide to controlling fire and explosion risks in the workplace.