Opening the laboratory

Purpose

To put the room into the state every practical page in this course already assumes, and to know it is in that state rather than hope it is. It takes about a minute once you have done it a few times.

When to use it

Before the first container is opened, every session, including the short ones. The short session is the one in which the tray is missing.

For dry work only — cutting paper, loading a tank, filing negatives, reading a data sheet — steps 3, 7 and 12 are the whole procedure and the rest does not apply. The moment a cap comes off, run the lot.

Before you start

You should already have drawn your own room to scale with the two areas, the air path, the waste station, the eyewash point and the spill kit marked on it, as the layout lesson asks; and read protecting yourself, which is where the controls this list sets out come from.

On the bench or within reach: the notebook; a containment tray for each vessel that will hold liquid; clean water and a separate rinse container; one graduate, funnel and pair of tongs per solution family; the labelled waste containers; the spill kit; eye protection and gloves; the safety data sheet for every product you will open.

Procedure

1. Open the window or start the extract, and open the make-up air path at the far end of the room from it — a door, a trickle vent, a gap under the door. A fan with nothing to draw is a fan straining against the room. The full version of steps 1 and 2, with the arithmetic and the three arrangements that do not work, is checking the ventilation; run that one when the room is new to you or has changed.
2. Check which way the air is moving. Hold a torn strip of paper at the doorway: it should lean towards the wet end. Air runs in at the clean end and out where the vapour is made, never the reverse.
3. Clear the bench, and confirm the dry area and the wet area are separated by a gap or a splash guard. Say aloud what happens on each.
4. Cover the wet surface if it is not already non-absorbent and lipped.
5. Stand a containment tray under everything that will hold liquid. Each tray holds the whole of the largest single vessel above it.
6. Put clean water on the bench, and a separate rinse container for hands and equipment.
7. Set out one graduate, funnel and pair of tongs per family, and read the family off each in words — DEV, STOP, FIX, WASH, SILVER — rather than by colour.
8. Set out the waste containers: one per stream, labelled, standing in a tray, with room in each for what this session will produce.
9. Find the eyewash point and reach it with your eyes shut, and prove the flow is tepid and gentle, by checking and using the eyewash. Move whatever is in the way.
10. Put the spill kit within reach of the wet bench and check that the gloves in it are unused.
11. Read sections 2, 4, 7 and 8 of the safety data sheet for every product you will open today, and write its version and revision date in the notebook.
12. Tell somebody in the house what you are doing and roughly how long you will be, as a sentence they will remember.
13. Put on eye protection and gloves, in the order donning and removing protective equipment gives. Before the first cap comes off, not after the first pour.

How you know it worked

• The paper strip at the doorway leans towards the extract.
• Every vessel on the bench, the waste containers included, can be identified without opening it.
• Nothing stands on an uncovered surface, and nothing that holds liquid stands outside a tray.
• You reached the tap with your eyes shut, at walking pace.
• The notebook carries today’s date, what you intend to do, and the data sheet versions you read.

If a step fails

Step 2, the strip leans away from the wet end. The extract is blowing rather than drawing, or the make-up air is on the wrong side. Reverse or reposition the fan, and work through checking the ventilation rather than adjusting by eye. If you cannot get the direction right, the session becomes dry work only: nothing is opened that makes a vapour, a mist or a dust.

Step 5, no tray large enough. Reduce the batch to what your largest tray would hold. Sizing the tray to the vessel and sizing the vessel to the tray are the same control reached from two ends.

Step 7, a vessel whose family you cannot read. Treat it as contaminated: wash it as though it had held fixer, relabel it in words, and note in the log that you had to.

Step 8, a waste container nearly full. Close, date and stow it now, at the start. Discovering it at the end of a tiring session is how a stream ends up in the wrong bottle.

Step 9, the eyewash point cannot be reached in a few seconds. Clear the route, or move the session to a bench where it can. This is the one item on the list that stops the session outright.

Step 11, no data sheet for a product. The product stays closed. Ask the supplier: one who cannot produce a sheet for a hazardous chemical has told you something worth acting on.

Step 13, the eye protection you own is not what the page asks for. Read which the page’s level requires. Safety glasses to a stated standard are the Level A baseline and ordinary spectacles are not eye protection at all; chemical splash goggles are what Level B means.

What to record

One line in the notebook, before you start: the date, what you intend to do, the data sheet versions and revision dates you read today, and anything on the list that was not true together with what you did about it. The last of those is the useful half — a session that opened with the spill kit in another room is worth knowing about when you next wonder why the routine slipped.