Article in “Technical Safety” Volume 9 from October 2019:
Sulfur dioxide is often used in the glass or metal industry as a shielding gas. It is usually installed in compressed gas cylinders for temperature control directly next to thermal processing plants. The necessary risk assessment of the storage of sulfur dioxide in accordance with §5 of the Occupational Health and Safety Act and §6 of the Ordinance on Hazardous Substances usually results in the obligation to store it in suitable storage facilities. Here, the proper storage in SO2 cabinets is presented, which reliably prevents a health hazard to the employees.
Sulphur dioxide concentrations in breathing air above the maximum workplace concentration of 2.7 mg/m³ of sulphur dioxide (SO2) in air can cause headaches, nausea and drowsiness in humans. At higher concentrations, the bronchi and lungs are severely damaged. SO2 cylinders are often stored indoors for temperature control, even directly next to thermal processing equipment, sometimes without any occupational health and safety measures. However, in order to protect the health of the employees staying there and to comply with the requirements of the Occupational Health and Safety Act, SO2 cylinders must be stored in a suitable storage facility. As part of the risk assessment in accordance with Section 5 of the German Occupational Health and Safety Act and Section 6 of the GefStoffV (German Ordinance on Hazardous Substances), the employer must determine whether the storage of hazardous substances can endanger employees or other persons. In Germany the following rules have to be complied with
- TRGS 510 Storage of hazrdous materials in transportable equipment
- TRBS 3145 / TRGS 745 Portable compressed gas containers – filling, providing, in-house transport, emptying
- TRBS 3146 / TRGS 726 Fixed pressure systems for gases The safety data sheet “Sulphur dioxide – SO2 liquefied under pressure” defines:
- H280 – Contains gas under pressure, may explode when heated
- H314 – Causes severe skin burns and severe eye damage
- H331 – Toxic by inhalation: Store separately from flammable substances
- P403 – Store in a well-ventilated area
- P405 – Store under lock and key: Suitable storage facilities are appropriately designed SO2 cabinets (Figs. 1 and 2).
The typical design of a suitable SO2 cabinet consists of:
- Safety gas cylinder cabinet for three sulphur dioxide (SO2) cylinders of 50 litres each and one nitrogen (N2) cylinder of 10 litres.