We use liquid nitrogen to freeze and store crystals and to operate the cold stream during data collection. Remember always to use personal protective equipment (especially the face guard and cryo-gloves) when working with liquid nitrogen.
Replenishing liquid nitrogen
Take empty nitrogen vessels (we own 141, a squat 160l vessel, and rent 141a, a refurbished tall 160l vessel) down into the enclosure outside Flowers. They are refilled every morning. Use the goods lift and the passage between Flowers and SEC, and return the filled vessel the same way. Be careful on rough surfaces as the wheels are relatively delicate. Make sure to pull the safety barrier across the lift doorway to prevent people from riding in the lift with liquid nitrogen.
The small tipping Dewar does not have a BOC account and will not be refilled if taken down. Refill it from either of the big vessels.