Gases and Reactions

Hydrogen

Nitrogen

Properties ◦ Flammable ◦ Small molecule - will leak ◦ Diffuses quickly ◦ Low spark ignition energy ◦ Not easily detectable (Colourless, odourless, tasteless) ◦ Asphyxiant

LEL 4% ; UEL 74.5% ◦ flammable at wide range ◦ eliminate ignition sources (0.000019 J) ◦ ventilate well to avoid LEL

Flames are invisible ◦ train workers ◦ check for leaks

Use your vendor ◦ safety information and training

Design your system well ◦ Outside! ◦ Eliminate ignition sources ◦ Follow piping and vessel industry standards ◦ Barricades against explosion

Colorless, Odorless, Tasteless Makes up majority of air (78%)

ASPHYXIANT

O2 % N2 % Consequence21 % 79 % Normal air

14 % 86 % Loss of ability to keep attention, to think clearly, some lossof muscular co-ordination. Pulse and respiration increase.

10 % 90 % Faulty judgement; no pain nor serious injury; rapid fatigue;very short temper, etc.

6 % 94 % Nausea; vomiting; legs give way. This may be the first andonly warning and it is too late. No pain. Resuscitation, evenif possible, may give permanent brain damage

< 6 % > 94 % Respiration by gasps, etc. RAPID DEATH.

Do not: ◦ enter enclosed spaces ◦ assume atmosphere in any tank, drain or other enclosed

space is safe to breath until it has been tested ◦ follow a fallen/distressed colleague into such a space ◦ even take a look!

Well trained and alert personnel Well designed systems Adequate ventilation Leak Prevention & Detection Elimination of Ignition sources Proper maintenance and inspection Proper process control ref; A. Stout, CFPA

National Fire Protection Association, NFPA Chemical Engineering Institutes (AIChE,

IChemE, etc) American Petroleum Institute (API) Occupational Safety and Health Authority DIN, BSI, etc.