Report of the Departmental Committee on Humidity and Ventilation in Cotton Weaving Sheds : [with minutes of evidence and appendices].

  • Great Britain. Home Office. Committee on Humidity and Ventilation in Cotton Weaving Sheds.
Date:
1909
Catalogue details

Licence: Public Domain Mark

Credit: Report of the Departmental Committee on Humidity and Ventilation in Cotton Weaving Sheds : [with minutes of evidence and appendices]. Source: Wellcome Collection.

    32/296 (page 2)
    6 January 1908. ] amount of moisture present, and I learnt, to my astonishment, that this was not the case; that no limit was placed upon the amount of steam admitted, and that this had naturally given rise to complaints ; that the moisture was frequently excessive, and that the health of the operatives suffered in consequence. “The remedy for this was easy, and forcibly illus- trated the benefits to be derived from the application of simple scientific principles to industrial affairs. I suggested that it would be perfectly possible to deter- mine by means of hygrometers the amount of moisture present in the air of the shed, and therefore to fix a definite limit which should not be exceeded. For this purpose I drew up a table which was afterwards in- serted as a schedule to the Act, and is to this day acted upon, showing how the amount of moisture must be regulated under seasonal and other changes of temperature, inasmuch as during the hot weather a larger absolute amount of moisture can be brought into the air of the weaving shed than during cold weather, without any inconvenience being experi- enced. These proposals were adopted by Government and became law in 1889. By these means a limit was fixed restricting the amount of moisture present in weaving sheds, this limit being controlled by the in- spector and open to the observation of both masters and workpeople.’’ I think that is a sufficient extract to quote to show what was in the mind of Sir Henry Roscoe. I was his assistant at the time. I only played an insignifi- cant part, and we had to look into this question, and it appeared to us that steam had been used indis- criminately—that there were valid reasons why it should be restricted. It was used excessively; it was used, as he says, without knowledge of the simple scientific principles governing its use; so we set to work to produce a schedule which would remove the excesses of moisture and produce a condition of affairs which would be more satisfactory. The value of that is proved by the results which have been obtained. Great improvement has taken place. 10. (Chairman.) Ut strikes me that what you read is very interesting, but it only tells us that Sir Henry Roscoe recognised an evil and set to work to remedy it, and he drew up tables which he says have pro- duced good results ?—Yes. 11. But he does not tell us on what he based his tables—whether it was a mere opinion that at certain temperatures a certain amount of humidity might be introduced. He does not tell us at all on what he based his opinions. Now these tables have been in use for a very considerable time, practically nineteen years, and I understand, so far as the operatives are concerned, they are not satisfied with them; they think that too much humidity is at times introduced. Now what we want to get at practically is what is really necessary for carrying on the trade. That, I think, is necessary to the weaver, who is a piece- worker, as much as it is to the manufacturer. The trade must be carried on, I take it; but what we want to arrive at is whether the trade can be carried on under conditions (whether they are healthful or whether they are otherwise) that will give reasonable comfort to the worker ?—Of course, Sir Henry Roscoe, in framing that schedule, had. to have regard to the conditions that are essential for the satisfactory carrying on of the process of weaving. It is a well established fact that moisture is essential to the process; and there- fore he had not very much difficulty in framing that schedule to protect the rights of the manufacturer and at the same time to remove the complaint of the operatives that they were exposed to excessive mois- ture. Now, when you come to look at that schedule, and say to yourself, How can I improve it; this has worked for so many years; can I improve it; can I give something which would be beneficial to the opera- tives and at the same time not take away from the value of the process of weaving?—then you are faced at once with a difficulty. You will notice on that schedule that up to a certain temperature the dif- ference between the wet bulb and the dry bulb is 2°. That was a great move. I have a great objection te refer to anything as a standard. A standard, in my opinion, must crystallise out of practical results. Although I use the word “standard” reservedly, I do not look upon it as a standard fixed for all time; but using it with that reservation as a standard it will simplify matters. He took 2° as the difference. We knew then we were so many degrees above the dew point. We knew of the general complaint, and that was the complaint that satisfied Sir Henry Roscoe and Sir William Houldsworth that something ought to be done. Sir William Houldsworth was a gentleman who interviewed Sir Henry Roscoe and discussed these problems, and from whose firm we veceived some knowledge, and that schedule is based upon some knowledge other than that of a purely scientific chemist. When we come to discuss high temperatures you will also notice that we raised the limit between the wet bulb and the dry bulb; there- fore we must have received some information from Sir William Houldsworth, who was in daily com- iunication with us, and who, as a matter of fact, was at the conference when we set to work to produce that table. Supposing that, instead of taking the difference between the wet and the dry bulbs, we take the reading as a matter of fact in this table for the sake of removing the excess of moisture or the liability to reach saturation point-—-supposing we had taken 3° more—that is, instead of having the difference be- tween the wet bulb and the dry bulb of 2°, we take a difference of 5°-—we are immediately producing. such a dry atmosphere that the manufacturer cannot use it; and I have prepared this afternoon, to illustrate it to you, and to make the whole thing, as it were, in a picture for you to realise, this diagram.* The top line, for instance, is the amount of moisture that is allowed under this present schedule in a cubic foot of air. This indicates in a graphic form the moisture that is allowed under the schedule. It is these figures set forth there in that picture on the top line. First of all, let me define what the operatives most object to, and what we personally would object to if we went into a mill and came out-—we should say we | felt chilly 1f we got hot in a mill where there was much moisture and came out into the open air, because there would be evaporation and condensation, pro- ducing a sensation of chilliness. That is what they most object to—it is what I call a chilly feeling. We experience that ourselves in coming from a hot, humid atmosphere into a dry one; you get condensa- tion. In other words, the operative can be compared to the wet bulb itself when he comes out and gets a chill. What he complains of is exactly what would happen to your wet bulb when you take it out from there into a dry atmosphere. 12, (Chairman.) Perhaps Mr. Cross or Mr. Shackle- ton can tell us whether that is what they really object to. It is not the feeling of being chilled, I think, but the excessive heat in summer. 18. (Mr. Shackleton.) There are two features; the point that is raised in the reference is also the exces- sive heat in summer. What Mr. Scudder refers to (Witness.) 1 am dealing now with the effect of. humidity. This is the principle I want you to rea- lise, and it takes a lot of consideration. Supposing you are in a humid weaving shed with a percentage of saturation of 88 and you are in an atmosphere of 75°, and you go into an atmosphere of 60° but with a saturation of 88 per cent., you feel no effect. The moisture is solely responsible for the chilling effect produced. If you are in a weaving shed at a temperature of 80° and the saturation is 88 per cent., and you walk out into a shed at 60° and the satura- tion is 88 per cent., you could not tell one mill from another, or if you opened a side door and slipped into another room. I want you to follow that, because that is one of the first things I would like you to satisfy yourselves of as a comment: that if you are in a place at a high temperature with a relative humidity of 88 per cent., and you leave that chamber and go into a room where you have a saturation of 88 per cent. but a lower temperature, you do not feel any chill. Now, I have put here in this curve, in a sort of diagram, the chill you would really experience coming out at these various temperatures. I have plotted on temperatures from 52° up to a temperature of 86°, because when I come to deal with temperatures I will show you how far you must regulate the tem- perature, so that at these various degrees of tempera- ture you are allowed that amount of moisture in the * Appendix IA.