The University of Iowa, Iowa City, IA 52242

TO: Director, National Institute for Occupational Safety and Health

FROM: Iowa FACE Program Date of Report: April 6, 1999

SUBJECT: Female machine operator killed when working on a punch press.

SUMMARY

A 43-year-old female machine operator died while working on a punch press on June 25, 1998. In this punch press machine, the die presses down and punches out a section of metal sheet, called a knockout, or scrap, which drops into the tray below the punch press. The front portion of the tray has a mesh guard for the machine. The tray slides out and the scrap can be removed. It is not unusual for the tray or basket to get full, and scrap removal may get backlogged. In this case, the die was positioned and set in place. After 130 presses, several slag pieces shot out from below the front portion of the machine, and many of these struck the victim in the neck, while other pieces were scattered on the floor. The victim was transported to a local hospital and died in the emergency room.

RECOMMENDATIONS based on our investigation are as follows:

  1. Ensure that machines are guarded as specified in 29CFR 1910.
  2. Designate a competent person to conduct frequent and regular site safety inspections.
  3. Develop, implement, and enforce a written safety program. The safety program should include task specific safety procedures and employee training in hazard identification, avoidance, and control.

INTRODUCTION

At 2:00 p.m. on June 25, 1998 a 43-year-old female died while working on a punch press at a machining facility. The victim was transported to a local hospital and died at 3:43 PM. The Iowa FACE program was notified of the fatality on October 20, 1998 by the Iowa Department of Public Health. The victim worked for the company for six months before the incident, although she had worked at the facility about 20 years ago. The first shift employees work from 7-4:30 p.m. On the day of the incident the weather was very hot and humid. Other environmental conditions did not contribute to the incident.

INVESTIGATION

In the punch press operation, the die presses down onto the metal and punches out a section in the middle of the sheet. This section is called the knockout, slag, or scrap. The scrap piece drops below the punch press into a tray. The front portion of the tray contained a mesh guard. The facility procedure specified that the tray should be cleaned out after 20 punch presses. For this process, the employee should remove the tray, dump the knockout pieces into a container for disposal, and replace the tray into the machine. Typically, if the scrap is not removed, the die may break or the machine becomes jammed.

The punch press is a machine that requires the undivided attention and good judgement of the operator. In this case, the die was positioned in place and a count of 200 was set. After 130 presses, the slag pieces shot out from below the front portion of the machine. Of the 130 slag pieces, several metal scrap pieces struck the victim in the neck and the remaining pieces were scattered on the floor.

The punch press tray was not returned to the machine after emptying, and was found beside the machine. The purpose of guarding was defeated when the tray was not returned to the machine after emptying. The purpose of machine guarding is to guard the point of operation.There are a number of common danger zones or ‘point of operations’ on punch press machines.

In many machining processes, the scrap or knockout removal may get backlogged. It is not unusual for the tray or basket to get full, and for staff to get behind in scrap removal. If you continually stop the process to remove the scrap, the employee can get behind, or run out of places to put the scrap. Resources are typically given to the machining process, and scrap removal or other housekeeping duties may not be emphasized.

Removal of parts and scrap should be designed into the operation. Accumulation of scrap within the die makes the guard difficult to use and may discourage their use. A fully guarded die eliminates access to the point of operation and efficient, reliable part and scrap removal is important. Unless scrap and parts removal is positively assured, the removal of guards may be encouraged.

One method to assure protection of the operator is to use a die that has attached to it its own complete guard that covers every hazard and allows only sufficient opening for the material to pass through. This would still provide the operator to position the material close to the die for maximum yield.

CAUSE OF DEATH

The medical examiner’s report stated the cause of death as severe hypovolemic shock, a consequence of a severe penetrating wound of the left neck.

RECOMMENDATIONS / DISCUSSION

Recommendation #1: Employers should ensure that machines are guarded as specified in 29CFR Part 1910.

Discussion: Any machine part, function, or process, which may cause injury, must be safeguarded. Employers must provide one or more methods of machine guarding to protect machine operators and other employees in the machine area from hazards such as those created by point of operation, in-running nip points, rotating parts, flying chips, and sparks. All such hazards located seven feet or less above the ground floor or working platform must be guarded to prevent accidental contact. Guards or fixed barriers may be attached to the frame, die, or base of a press to prevent the operator from the point of operation. Guards must be attached to the machine, or secured elsewhere if attachment to the machine is not possible. Additional recommendations for power presses are contained in 29 CFR 1910.217. In this case, the purpose of guarding was defeated when the tray was not returned to the machine after emptying. If the tray was in place, the scrap pieces may have shot out and hit the mesh guard, causing no injury to the employee.

Recommendation #2: Employers should designate a competent person to conduct frequent and regular site safety inspections.

Discussion: Regular inspections of the work site by a competent person ensure that safety procedures are being followed, and demonstrate that the employer is committed to the safety program and prevention of injuries. Scheduled and unscheduled inspections of the jobsite, materials, and equipment should be conducted to identify hazardous conditions.

In this case, the punch press tray was not returned to the machine after emptying, and was found beside the machine. Regular inspections would have identified the problem and noted whether this practice was common in the facility.

Recommendation #3: Employers should develop, implement, and enforce a written safety program. The safety program should include task specific safety procedures and employee training in hazard identification, avoidance, and control.

Discussion: The implementation and enforcement of a comprehensive safety program is designed to prevent worker injury. The safety program should include task-specific safety procedures and employee training. Training is a critical element in an integrated safety program and should include the communication of task-specific safety procedures and training in the avoidance and abatement of these hazards. Employees should have the knowledge, training, and experience to perform the job that he/she is designated. In this case, the victim worked at the facility previously. Re-training is essential and each employee should work under the close supervision of a designated person until the employee is able to demonstrate the ability to safely perform the new job independently.

____________________________________________________________________________

Lois Etre PhD. Wayne Johnson MD.
Industrial Hygienist/Investigator Chief Trauma Investigator
Institute for Rural & Environmental Health Institute for Rural & Environmental Health
The University of Iowa -- Iowa City, Iowa The University of Iowa -- Iowa City, Iowa
 

REFERENCES

National Safety Council. Accident Prevention Manual for Business & Industry: Administration and Programs. Tenth Edition. Chicago, IL. 1992.

Office of the Federal Register: Code of Federal Regulations, Labor 29 Part 1910. Washington, DC: U.S. Government Printing Office, 1996.

NIOSH Current 49. Injuries and Amputations Resulting from Work with Mechanical Power Presses. Publication No 87-107, 1987.