This matter is before us on the petition of Rockwell Manufacturing Company, Kearney Division, hereinafter called “Rockwell,” to review1 and set aside the decision and order2 of the National Labor Relations Board.
The Board found that Rockwell violated § 8(a) (5) of the National Labor Relations Act, by refusing to recognize and to bargain with United Steelworkers of America, AFL-CIO, hereinafter called the “Union,” as the authorized representative of Rockwell’s employees, and by granting unilateral benefits to Rockwell employees; and that Rockwell further violated § 8(a) (1) by coercive interrogation of employees concerning their union activities and sympathies, and by threatening reprisals or promising benefits to induce abstention from such activity.
In its answer, the Board has requested enforcement of its order. No jurisdictional issue is presented.
On February 19, 1962, the Union filed a representation petition with the Board seeking certification as bargaining agent for Rockwell’s employees.
On March 6, 1962, Rockwell and the Union entered into a Stipulation for Certification upon Consent Election to be held March 21, 1962, at Rockwell’s plant in Kearney, Nebraska.
We need not detail the facts on which the Board bases its finding of § 8(a) (1) violation through interrogation, prior to the election, as Rockwell states it will not contest these findings, although in Rockwell’s opinion, the Board did not correctly resolve the issues of credibility involved in assessing and weighing the testimony.
The election was held, and the Union won by 50 to 49, with one ballot held to be void. Rockwell filed timely objections to the election, alleging that a general atmosphere of anxiety had been created among the employees prior to the election, by Union suggestions to use force in enlisting members, threats of physical harm to non-Union supporters, and Union instruction in making paint bombs for possible use against the latter.
These objections were investigated by the Board’s Regional Director who recommended they be overruled. Rockwell filed exceptions to this report. The Board sustained the Regional Director’s recommendations and certified the Union.
Rockwell posted a notice to its employees indicating that it would not bargain with the Union because it felt that it had been denied due process and proper hearing on the matter of Union intimidation; that Rockwell would force the matter into the federal courts by refusing to accept the Board’s decision in an effort to protect the interests of its employees.
Accordingly Rockwell refused to meet and bargain with the Union. In November, 1962, certain wage increases, an additional paid holiday, and some medical benefits were granted unilaterally without notice to or consultation with the Union. Rockwell explains that it was precluded from consulting with the Union as it hoped by non-recognition to secure a hearing on its charges that the Union had been guilty of coercion of Rockwell’s employees in the pre-election period.
The Board asserts that in its objections Rockwell raised no issue which would justify setting aside the election. Whether to set aside an election because of incidents during the campaign period is a matter for the sound discretion of the Board. As has been frequently remarked :
“ * * * Congress has entrusted the Board with a wide degree of discretion in establishing the procedure and safeguards necessary to insure the fair and free choice of bargaining representatives by employees.”
*797N. L. R. B. v. Waterman Steamship Corp., 309 U.S. 206, 226, 60 S.Ct. 493, 84 L.Ed. 704 (1940); N. L. R. B. v. A. J. Tower Co., 329 U.S. 324, 330, 67 S.Ct. 324, 91 L.Ed. 322 (1946); Olson Rug Co. v. N. L. R. B., 7 Cir., 1958, 260 F.2d 255, 256-7.
Several of the incidents on which Rockwell’s objections rested occurred during the critical period, i. e. after the consent to election. After certification of the Union, the Board changed its procedures, effective prospectively only, to consider (as grounds for setting aside a consent election) such electioneering conduct as occurs during the period beginning with the petition for election.
Consideration was given to threats made on two occasions by Duane Taylor, a Rockwell employee who favored the Union, but who held no position in it, to Mr. Hayes, another employee who was opposed to the Union and who stated that he voted against it. He also told the Board’s investigator that he did not take the first threats seriously, that he did not believe them, and laughed at them. Two other employees who were present also said “It was all in fun.” Mr. Hays reported only the second threat to his foreman, but at that time, he stated, he was not afraid of anything Mr. Taylor could do to him.
Another incident, involving paint bombs, was originally understood to have occurred after the consent to election and was investigated and considered. In its subsequent offer of proof in connection with the charges of refusal to bargain with the certified Union, Rockwell placed the date of this incident as about February 22,1962, or before the consent to election, on March 6,1962, which marked the cut-off date then in effect.
The Board investigator reported that all those questioned said that the matter came up at a Union meeting in connection with distribution of anti-Union literature; that someone asked what a paint bomb was. In the subsequent offer of proof, Rockwell offered to call witnesses who would testify that instructions on making paint bombs were given in response to a question: “How do you brand a scab?”
Although the Union official present asserted that the Union was seeking to make friends and recommended no violence, he did explain just how to make and use a paint bomb.
The Regional Director reported no evidence that this disclosure went beyond the meeting or received any publicity.
The Board has always considered it a question of degree whether the conduct revealed by the record is so glaring as to impair the employees’ freedom of choice, necessitating a new election. General Shoe Corp. (1948) 77 NLRB 124, 126.
Each incident must be considered in the light of the precise circumstances of a particular case, having reference to the timing, proportion of employees affected, and the character of the threat.
As the exceptions filed to the Regional Director’s report alleged no additional evidence which the Regional Director had overlooked respecting these incidents which were considered by him, the Board found no material issue of fact necessitating a hearing, and Rockwell’s request for a hearing was denied, pursuant to the Board’s rules and regulations, under which the Board may direct a hearing.
* * * if it appears to the Board that such exceptions raise substantial and material factual issues, * * *
The Board requires specific evidence of conduct which prima facie would warrant setting aside the election. N. L. R. B. v. O. K. Van Storage, Inc., 5 Cir., 1961, 297 F.2d 74, 76.
At the unfair labor practice stage of the litigation, however, the Board is not required to consider new allegations and evidence pertinent to the representation issues, which could have been advanced at that earlier stage. Allis-Chalmers Mfg. Co. v. N. L. R. B., 7 Cir., 1947, 162 F.2d 435, 440-441. The Board accordingly rejected the offer of proof made at *798that stage of the proceedings. We cannot agree with Rockwell that the Board exceeded its authority, nor can we concede that such exceptional circumstances were shown here as to require a departure from the Board’s established and reasonable practice. Rockwell’s offer of proof at the unfair labor practice stage concerned the same two objections which the Board had treated. No reason was advanced for failure to adduce at the initial proceedings, any additional evidence listed in the offer of proof at the later stage of the case.
The Union was certified in August, 1962. On September 5, 1962, in Goodyear Tire & Rubber Co., 138 NLRB 453, 455, the Board announced that it would consider conduct occurring any time after the representation petition was filed, but with respect only to petitions filed after September 17, 1962. The new rule would be inapplicable, not only to elections such as Rockwell’s, which had been decided, but even to any of the numerous pending cases wherein the petition was filed prior to September 17, 1962.
Rockwell considers this procedure arbitrary and highly prejudicial to Rockwell, because it cuts off consideration of incidents prior to the consent date, outlined in Rockwell’s offer of proof at the unfair labor practice stage. These alleged incidents included at least three open threats of violence by pro-Union against anti-Union employees, and a statement, by the same Union official who had described paint bombs, to the effect that “there was more than one way to get union authorization cards signed, such as using pressure or getting rough.”
When in Goodyear, supra, on September 5, 1962, the Board set the cut-off date as the date of the petition, in consent elections, the rule was made applicable for a future time consistent with the policy in the case of Ideal Electric & Mfg. Co., December 14, 1961, 134 NLRB 1275, 1278, where it was said:
“Finally, we have concluded that in order to avoid undesirable confusion as to the impact of this new policy on cases currently pending before the Board, we shall not apply the new policy enunciated herein to the instant case or to others now pending * * *”
Similarly, the Board here contends that any other course of action would raise questions necessitating reinvestigation of a number of pending cases. The Board refers to its 27th Annual Report as showing that 5,432 elections of this type were conducted during the fiscal year ending June 30, 1962, and that 2,060 representation cases of all types were pending on June 30,1962.
While Rockwell’s individual situation excites our sympathy, we must admit that providing for prospective application of the new rule was neither arbitrary nor capricious. The Board may fix the effective date of its rule changes and apply its standards prospectively. N. L. R. B. v. Red Rock Co., 5 Cir., 1951, 187 F.2d 76, 78, cert. den. 341 U.S. 950, 71 S.Ct. 1017, 95 L.Ed. 1373; Optical Workers Union, etc. v. N. L. R. B., 5 Cir., 1955, 227 F.2d 687, 691, and 5 Cir., 1956, 229 F.2d 170, 171, cert. den. 351 U.S. 963, 76 S.Ct. 1027, 100 L.Ed. 1484.
Rockwell’s petition for review is denied. The Board’s order will be enforced. Enforcement Ordered.
. National Labor Relations Act, as amended, Title 29 U.S.C. § 151 et seq., § 160(f).
. Reported 142 NLRB No. 86, 63-1 CCH NLRB 19,285, issued May 23, 1963, amended June 25, 1963.