WARNING TM    5-6630-215-12 (b)   The   hardness   test   is   the   most   frequently   performed   anal- ysis  in  the  water  industry. Large   amounts   of   hardness   are   undesirable for  aesthetic  and  economic  reasons  in  many  industries  and  must  be removed  before  the  water  is  suitable  for  use;  e.g.,  the  beverage, food,  laundry,  metal  finishing,  dying  and  textiles,  and  pulp  and  paper industries. Levels  about  500  mg/l  hardness  are  undesirable  for domestic  use  and  most  drinking  water  supplies  average  about  250 mg/l. Keep  all  bottles  tightly  closed. Do  not  allow chemical  reagents  to  come  in  contact  with  eyes. Most   chemical   reagents   are   corrosive   or   poisonous or both. Buffer  Solution  Hardness  No.  1. For  test  purposes only. Cause   irritation. Avoid  contact  with  skin and eyes. Keep  well  closed. External    contact: flush  with  water. Ingestion: give  plenty  of water  or  milk. Follow  with  a  dose  of  milk  of magnesia. DO  NOT  induce  vomiting. Call  physi- cian. For  laboratory  use  only. Keep  away  from children. Manver  Hardness  Indicator  Hardness  No.  2. May cause   irritation. For  test  purposes  only. Avoid prolonged   and   repeated   contact   with   skin. Keep well  closed. External   contact: flush  with water. Ingestion: give  plenty  of  water  or  milk. Induce   vomiting. Call   physician. For   laborator use only. Keep  away  from  children. Titration  Solution  Hardness  No.  3. Harmful  or fatal  if  swallowed. Contains   ethylene   glycol. Avoid   prolonged   and   repeated   contact   with   skin. Keep  well  closed  in  cool  place. External   contact: flush  with  water. Ingestion: give  plenty  of water  or  milk. Induce   vomiting. Call   physician. For  laboratory  use  only. Keep  away  from  children. Potassium   Hydroxide   Solution   8N. Poison. May cause  burns. Contains    potassium    hydroxide. Avoid  contact  with  skin,  eyes,  and  clothing. Keep  well  closed. External   contact: flush  with water. Eye  contact: Irrigate  with  water  for  10 minutes. Call   physician. Ingestion: give plenty  of  water  or  milk. Follow   with   citrus juice  or  diluted  vinegar. Induce   vomiting. Call physician. For  laboratory  use  only. Keep  away from   children. 2-73