6.5.There are 6 General ventilation system or a hazardous chemical that causes dilution or a vacuum air only where appropriate to the kind of dangerous chemicals. With oxygen in the atmosphere is lower than 10 per cent in the nine five-point by volume.
6.5.6 a general ventilation system. Or a chemical solution. Or a vacuum ventilation. Appropriate to the type of dangerous chemicals. The presence of oxygen in the atmosphere, not less than nine point five percent by volume.
6.5.6 ventilation system in general. Or that the dangerous chemicals dilution. Or the suction air only. Appropriate to the types of hazardous chemicals. The oxygen in the atmosphere than nineteen point five percent by volume.