Wilhelm Jost Institut Förderverein e.V.

Safety Technical Indices

General 

In the context of this purely informal overview a set of safety-relevant characteristics are to be introduced which should be known for the characterisation of inflammable liquids, gases and steams in respect of the safety-relevant interpretation of plants.

It pertains to this:

  •             Explosion Limits (LEL und UEL),
  •             Limiting Oxygen Concentration,
  •             Flame Point, Lower Explosion Point
  •             Conductivity
  •             Ignition Temperature,
  •             Minimum Ignition Energy (MIE),
  •             Flame speed,
  •             Border Die Gap,
  •             Maximum Explosion Pressure (Pmax)
  •             Maximum rate of pressure rise (KG).

In detail the characteristics are defined briefly, the appropriate testing methods are presented and a description of the safety-relevant meaning of characteristic numbers are given.

Ignition temperature

Definition:

The ignition temperature is the lowest temperature of a hot surface at which the inflammation of an inflammable material as gas/air or steam/air mixture occurs. The ignition tempeature is determined under prescribed test conditions.

Read more ...

Lower Explosion Point (LEP)

Definition:

 The lower point of explosion is the temperature of a combustible liquid where the concentration of saturated steam in air is equal to the lower explosion limit.

 

Read more ...

Maximum explosion pressure and maximum rate of pressure rise

Definition:

 

The explosion overpressure pm and the rate of pressure rise dp/dt describe the violence of reaction of dust/air mixtures of random concentration after ignition in a closed vessel. The maximum explosion pressure pmax and the maximum rate of pressure rise (dp/dt)max of combustible dusts are determined in closed standard equipment by means of tests over a wide range of concentration.

Read more ...

Limiting Oxygen Concentration

Definition:

The limiting oxygen concentration is the maximum oxygen concentration in a mixture of a fuel with air and an inert gas , in which no explosion can occur.

Read more ...

Minimunm Ignition Energy (MIE)

Definition:

 

The minimum ignition energy (MZE) is the smallest electrical power stored in a condenser, which sufficiently ignites an ignitable mixture of a combustible atmosphere by an electrical discharge. The MIE is determined under prescribed test conditions.

 

Read more ...

Conductivity (electrical)

Definition:

 

The electrical conductivity is a measure for the electrostatic rechargeableness of liquids and is usually indicated in the unit pS/m.

Read more ...

MyCloud