!!! Important !!!
For vehicles equipped with a gas drive system (CNG or hydrogen), all the following information, relevant to the vehicle, must be observed in order to assess safety after an accident, a fire or any problems with the gas drive system before starting work!
| Check | ||
Danger | Risk of explosion due to escaping combustible gas or overheating of gas cylinders.Risk of injury caused by burns to skin and eyes. Risk of frostbite to body parts caused by escaping gas and by touching components near the valves when emptying gas cylinders. Risk of poisoning or suffocation caused by inhaling gas. | Remove any sources of ignition. | |
Danger | Risk of fire/risk of explosion due to short circuit and escaping oxyhydrogen gas. Risk of (burn) injury caused by caustic burns to eyes, skin and mucous membranes from battery electrolyte/mist, short circuit and arcing. Risk of poisoning caused by swallowing battery electrolyte or absorption of lead through the skin or body orifices. Risk of death due to voltage U >= 30 V AC and U >= 60 V DC. | No fires, sparks, open flames, or smoking. Wear acid-resistant gloves, clothing, and glasses. Pour battery acid only into suitable and appropriately marked containers.Model 253.992/993 | |
Danger | Risk of death when working on component parts and systems with U >= 30 V alternating voltage (AC) or U >= 60 V direct voltage (DC) | Do not touch damaged or defective live component parts and lines or non-insulated electrical connections and lines.Model 253.992/993 | |
Danger | Risk of explosion caused by escaping hydrogen or overheating of the fuel tanks when working on the hydrogen system. Risk of frostbite to body parts caused by escaping gas and by touching component parts carrying gas when emptying fuel tanks. Risk of asphyxiation caused by inhalation of air diluted by hydrogen. Risk of burn injuries by coming into contact with an invisible pale blue hydrogen flame. | Model 253.992/993 | |
Topical note | General information on handling vehicles with high-voltage on-board electrical system and/or lithium-ion battery and/or gaseous-fuel drive system | ||
Topical note | Notes on battery | ||
Topical note | Notes on fuel cell system | Model 253.992/993 | |
Topical note | Notes on working on natural gas powered vehicles | Model 211, 212 | |
1 | Check whether you have the required level of qualification for assessing the safety of the gas drive system (CNG or hydrogen) | The required Mercedes-Benz/smart specific qualification/instructions can also be obtained from Mercedes-Benz Global Training. | |
Do you have the required qualification? | |||
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If the answer here is no, you may not carry out a safety assessment on vehicles equipped with a gas drive system (CNG or hydrogen)! | |||
If the answer is yes, continue with operation step 2 | |||
2 | Check gas drive system (CNG or hydrogen) before starting work for any acute gas leak | ||
Topical note | Requirements for driving into the workshop | Model 253.992/993 | |
General information on leak testing for natural gas systems | Model 211, 212 with engine 271 | ||
3 | Perform special service, gas system test | The gas system test must be performed after every opening of gas carrying component parts in the gas drive system or after an accident or a fire or thermal exposure > 85 °C / 185℉ at the gas cylinder, high-pressure gas carrying lines, connections and valves. | |
| Model 211 | ||
| Model 245 | ||
| Model 212 | ||
| Model 242 | ||
| Model 253.99 |