Both transport companies will draft in their reserve drivers to use in emergencies. These reservists are often either former drivers who have moved on to office jobs but are still qualified to drive trains.
French media are reporting that both companies are planning to make the weekend of December 7th and 8th a 'sacrifice weekend' with very few services running, in order to concentrate their resources on running a skeleton service during the week.
The reserves were last used in Paris in September during a one-day strike in order to retain a skeleton service. Although many Metro lines did not run at all, there were about 40 percent of suburban RER services running and around 30 percent of buses.
This time matters are made more complicated by the length of the strike, which is currently 'unlimited'.
Unions are beginning the action on Thursday, December 5th, but many have issued unlimited or renewable strike notices and union officials say they will stay out for as long as they need to.
Transport companies are already planning ahead for more than a one-day strike with SNCF and Eurostar not taking bookings between December 5th and 9th and Lyria – which runs international train services – offering free exchanges or refunds until December 11th.
Many French workers have already opted to take December 5th and 6th as holiday or claim back time owed in lieu, so transport companies are reporting that Monday, December 9th is likely to be the most difficult day as commuters return to work and peak time lines struggle to cope, so are concentrating most of their resources on that day.
It means that for anyone trying to get around in Paris on the weekend of December 7th and 8th services are likely to be very limited indeed.
Fortunately there are plenty of other options – expanded cycle lanes, bike hire schemes, electric scooters or walking. And RATP has entered into a partnership with some bike hire firms and VTC firms like Uber and carsharing oferin deals to commuters.
At only 9km across, Paris is a very compact city, perfect for walking, seeing the sights and generally soaking up the atmosphere.